maybe tubes are not that great? I do not know! HELP!

[tube fanatic]

It should be very obvious that there is no answer to the OP's question since every audio installation is different, and every listener has some personal criteria which can't be fully comprehended by others.  K-horns in one room will behave very differently from their performance in another room.  Variables such as room size, furnishings, proximity of the listening position to the speakers, height of the listeners ears relative to the drivers, type of music, level at which music is played, ambient noise levels, crud coming in on the AC powerlines, and countless other issues will all determine the type of amplifier which will best serve that particular installation.  So, the only way to make a judgment is to find some way to try as many different types of amps as possible and draw your own conclusions.  The nice thing about low power tube amps is that the cost can be small enough to make some DIY projects feasible.  And, it certainly allows a person to try different circuit arrangements including SETs and SEPs with and without feedback, ultralinear, push-pull, and so on.  The same for some of the lower cost SS designs which Nelson Pass has offered.  If I'm not mistaken, the OP mentioned going through some Navy electronics training.  And, he did repair a cold solder joint in one of the Quicksilver amps.  That level of experience is certainly sufficient to allow construction of a tube amp kit (and those can be had for a couple of hundred dollars), if not a full DIY project.  And, the last point I want to make is that synergy between the amp and speaker is absolutely critical.  Depending on a speaker's impedance and phase angle variations over the audio band, one type of amp may be better suited than another.  Unfortunately, other than some general rules about this, the best combination often has to be determined by experimentation.  Some online sellers of equipment recognize this and offer in-home trials for that reason.

Maynard.    

[Zim.]

x

[Zim.]

x

[NOSValves]

What Audiophile world uses a SET amp as the ultimate to judge all amplifiers by? Not the one I live in. SET amps are about the smallest part of the market place. The only thing that keeps the fires burning is the few owners of these amps never shut up about them. Its like they spend more time justifying there choice to the world then they do listening to them. 

[Fjd]

On ‎4‎/‎7‎/‎2016 at 7:09 PM, Zim. said:

 

On ‎4‎/‎7‎/‎2016 at 6:05 PM, wdecho said:

From the master,

 

 "What this country needs is a good 5 watt amplifier" (Paul Klipsch).

 

Since the beginning of amplification single ended triodes have been acclaimed as the ultimate in sound reproduction. If the low 5 or 6 watt SET's are not good enough for our 100db speakers exactly what kind of speaker are they good for. The highly acclaimed SS designer Nelson Pass has devoted a considerable amount of his time trying to duplicate the single ended triode tube sound with SS devices. Audiophile reviewers worldwide still acclaim SET as the ultimate in sound reproduction and all other forms of amplification is judge on how it compares to the SET. 

 

There are still people that believe OJ did not do it or the world is not round. It does no good to argue with them.

 

You have to be the judge of what sounds good to you and buy what you think is best. What I have just said is just cold hard facts. What anyone hears is not reality but our own interpretation of it. When someone works hard for their money they should be able to spend it as they choose to not by what anyone else says. 

 

Since you bring up PWK, could you tell me some of the SET amps he used?   Or for that matter any tube amps that he used later in his life when SS became a viable option to the tubes?  Forgive my ignorance but I am only aware of his early favorite (modded Brooks 12A  2A3 PP of 10W. or so), and latter the various pro SS amps from Crown, BGW, etc.  

 

 

 

On ‎4‎/‎7‎/‎2016 at 7:23 PM, Zim. said:

I'm sure he certainly had excess to any amp. at his disposal, yet when SET amps galore were so easily available he still made the call "What this country needs is a good 5 watt amplifier".   Why would he say such a thing if the SET was the ultimate circuit and at the same time so attainable?   Why would he only endorse the modded Brooks and not a SET?

 

 

 

I think we have somehow created our own “red herrings” that we are now chasing upstream.  In many of the articles where we have jumped to conclusions that Paul was promoting one type of amplifier topology over another, our conclusions appear to be incorrect and he is really expounding upon how well-engineered his Klipshorn speakers are.  When it comes to amplifiers, I believe that PWK was primarily pointing out a simple mathematical relationship and facing an economic reality of the times he lived.

 

After reviewing a multitude of evidence for which I have outlined a few key points in more detail below, I tend to hold the view that I don't think PWK can be used as an advocate of low powered SET amplifiers any more than he can be used as an advocate for mid-power solid state amplifiers.  Although, in one of the “Dope From Hope articles” he does state that “In a typical living room or small theater, our present all-horn systems offer concert-hall levels with a mere 10 watts peak input.”  There again, PWK specifically stated 10 watts, not 5 watts, and I believe his statement was a tribute to the engineering of the loudspeaker in that it could reproduce concert-level SPL with fairly low power (e.g., doing the math), not an endorsement of any specific amplifiers or amplifier topologies.

 

The simple fact of the matter was, is, and always will be, the Klipschorn speaker efficiency allows a person to use very low-powered amplifiers if that type of amplifier meets that person’s listening requirements, regardless of whether that choice is SET, SEP, Push-Pull, solid state, or otherwise; and as I have noted in other posts, the Klipschhorn will reveal very quickly if the amplifier sucks or the source sucks or both suck.

 

After spending a very substantial amount of time revisiting the “Dope From Hope” articles and various other documentation (including the pages of “Klipschisms, quotes and anecdotes" attributed to PWK on the main website), I also could not substantiate that PWK explicitly voiced, or had written the quote often attributed to him that "What this country needs is a good 5 watt amplifier."  Without specific credible evidence, especially given that PWK was looking for concert-level reproduction of 115dB SPL at the listening position, I'm now wondering if the quote is a type of urban legend that has proliferated over the internet, similar to the Robert Hartley situation I describe below (e.g., in PWKs situation outlined below, 5 acoustic watts = 20 amplifier watts, not 5 amplifier watts).

 

Jim Hunter, just where are you when we need you?  

 

Since the written records appear to clearly show that PWK loved his push-pull 10 watt per channel Brook 12A amplifier, he may have actually been complaining that amplifiers of his time were not powerful enough, in addition to not being good enough. 

 

The written information appears to show that, in addition to PWK liking the Brook 12A amplifier at first, he then moved to a variety of mostly solid state amplifiers in the range of approximately 60 watts per channel.  I have also found references where he used a lot of different brands including Crown (D60) and BGW (model 100).

 

An interesting side note with the Klipschorn history in relation to the Brook amplifier is that Paul (and Brook) collaborated to squeeze more [power] from the 12A amplifier (a 2A3 push pull design) and developed modifications to address some bass deficiencies that were revealed by the Klipschorn speakers.  The modification subsequently became a factory mod available to optimize the amplifier to the Klipshorn and was given the catalogue number of “12A3-KI.”

 

I have also found that there are many other references in his literature where he recommended 20 watts per channel amplifiers as a minimum for Klipschorns.  Keeping in mind that one goal that PWK had often articulated in both verbal and written form, was that his loudspeakers were capable of reproducing concert-level sound of about 115dB at the listener's position, and here is one such reference from the "Dope From Hope" Vol. 14, No. 2 May 1974 titled "Power Ratings."

 

"[''What size amplifier shall I buy?" This is really the first of two questions. The answer, applied to KLIPSCH speakers, would be a maximum of 100 watts (sine wave rating) per side. If a higher power is used, precautions may be needed to prevent speaker damage.  Crown suggests a one ampere fuse for each channel.

 

The second question, I think we can assume, is fishing for a realistic relation between sound pressure level and amplifier power.  Accept the figure that 115 dB peak sound level pressure at the listener's ear will be as loud as what you would hear at a live concert. (A sound level meter would read 103 dB at "maximum" swings, because a V.U. meter has a "delay" or "lag", and instantaneous peaks are about 13 dB higher than the meter reading peaks).

 

In a typical 4000 cubic foot listening room, this requires 40 peak amplifier watts to feed a group of high efficiency loudspeakers: assuming this to be 2-channel stereo, 20 peak watts per channel or 10 watts average sine wave power rating per side is required. For a low efficiency speaker (of the typical so-called air suspension type) over 100 times as much amplifier power would be necessary: that makes over one kilowatt of sine-wave rated power for each channel.]"

 

In the "Dope From Hope" (Vol. 8, No. 1 July 11, 1967) article titled "Guarantee Void" PWK stated that, "[back in the good old days of 10 and 20 watt amplifiers it was uncommon to experience loudspeaker failures. When 75 watts became common, occasional tweeter failures began to occur. Then with the advent of large solid-state amplifiers with their 240 instantaneous power peaks, tweeter failures became epidemic and woofers began to come apart at the compliance rings and voice coils began to tear loose from cones.]"

 

Another misnomer that I found was that PWK often referred to “acoustic watts” and invariably magazine writers (e.g., Robert Hartley), among others would drop the “acoustic” and just state watts, which was misleading and only perpetuated inaccuracies.

 

The following are PWK definitions published in the "Dope From Hope" (Vo. 9, No. 2 June 1973) article titled "Definitions."

 

WATT

 

First of all a watt is a unit of power or rate of doing work, whether electrical, mechanical, thermal or acoustic. Equivalents are 0.738 foot pounds per second, 0.238 calories per second, or

 

w = e^2/z

 

Where w is watt, e^2 is electrical pressure or electromotive force in volts and z is electrical impedance in ohms.

 

The acoustic watt may be similarly expressed in terms of acoustic sound pressure p in dynes per square centimeter and the acoustic impedance of air which has been derived as the product of the air density times the velocity of sound p thus w = p^2/z.

 

When the sound pressure level is 100 dB, the sound power transmitted is 10^6 watt per square centimeter. (The 100 dB level is referred to zero dB = 0.000204 dynes per square centimeter: thus 100 dB = 20.4 dynes per square centimeter).

 

ACOUSTIC WATT

 

Translating the above numbers into something quickly useful, it turns out that a sound source radiating from a trihedral corner with a uniform polar pattern will be radiating one watt of power when the sound pressure measured at 4 feet is 118 decibels.

 

Essentially, it came down to PWK’s literature recommending 20 watt amplifiers as the minimum for Klipschorn loudspeakers to meet his Klipschorn design goal of producing concert-level sound of 115dB SPL at the listener position.

 

In my reference to Robert Hartley, I’m referring to excerpts from his book titled, "the Complete Guide to High-End Audio" where the excerpt can also be found in the article "How Much Amplifier Power Do You Need" where he writes that “loudspeaker pioneer Paul Klipsch conducted a demonstration of live vs. reproduced sound with a symphony orchestra and his Klipschorn loudspeakers. His amplifier power: 5W. The Klipschorns are so sensitive (an astounding 105dB SPL, 1W/1m) that they will produce very high volumes with very little amplifier power. Klipsch was attempting to show that his loudspeakers could closely mimic the tonal quality and loudness of a full symphony orchestra.”

 

If anyone has been following the various posts in the “high power amplifier” thread, I would have a hard time believing that someone could still conclude that a 5 watt amplifier would attain that type of concert level SPL in a theater where a symphony orchestra was playing.

 

The reference indicates that PWK talks about a symphony orchestra and 5 watts; however, he is not talking about a nominal 5 watts.  I believe that PWK is actually talking about 5 "acoustic watts" as he has defined an acoustic watt in the Dope From Hope that I have excerpted above.  Note that PWK has also put into print, including references in the Dope From Hope, a 20 watt per channel amplifier is suggested for full live symphonic dynamics (e.g., 115 dB at the listening position).

 

To achieve the 5 acoustic watts in the room that PWK is talking about, he had two Klipschorns and a Belle with each channel connected to 20 watt amplifiers.  Once I crunched the math considering the definitions in the "Dope From Hope" (Vo. 9, No. 2 June 1973) for an acoustic watt, it became pretty obvious what happened in that I suspect that Hartley may not have understood the concept of an acoustic watt or just dropped the word "acoustic" in his text. 

 

Essentially, there you have it in that it seems that PWK has outlined various situations that appear to indicate that for 2-channel stereo, 20 peak watts per channel or 10 watts average sine wave power would cover the concert level SPL THAT he had personally strived to achieve.

 

 

[NOSValves]

http://www.6moons.com/audioreviews2/audioreviews.html

 

I've actually talked to Srajan Ebaen on  few occasions Craig. Maybe you can discuss how your 30 year year old design you have copied is so much better than anything they have ever heard with him and send him one of your amps for a review. You can fool the less knowledgeable members on this forum with your sales pitch at every chance you get but you will not be able to stay in a room with real amplifier designers. 

 

I would love to see the square wave response you were bragging about from an independent unbiased lab. Your avatar pretty much says it all. 

 

Also I thought we had an agreement but I never thought you would abide by it.  The only market place you have is this forum and the members here but only the ones that do not understand amplifier technology. How you get away with pitching your product when others are not allowed to do so is beyond me. 

 

 

My Avatar is directly out of PWK play book.... so now your saying I'd post false information about my products....mighty bold of you. Sounds like a personal attack to me. 

[NOSValves]

 

 

From the master,

 

 "What this country needs is a good 5 watt amplifier" (Paul Klipsch).

 

Since the beginning of amplification single ended triodes have been acclaimed as the ultimate in sound reproduction. If the low 5 or 6 watt SET's are not good enough for our 100db speakers exactly what kind of speaker are they good for. The highly acclaimed SS designer Nelson Pass has devoted a considerable amount of his time trying to duplicate the single ended triode tube sound with SS devices. Audiophile reviewers worldwide still acclaim SET as the ultimate in sound reproduction and all other forms of amplification is judge on how it compares to the SET. 

 

There are still people that believe OJ did not do it or the world is not round. It does no good to argue with them.

 

You have to be the judge of what sounds good to you and buy what you think is best. What I have just said is just cold hard facts. What anyone hears is not reality but our own interpretation of it. When someone works hard for their money they should be able to spend it as they choose to not by what anyone else says. 

 

Since you bring up PWK, could you tell me some of the SET amps he used?   Or for that matter any tube amps that he used later in his life when SS became a viable option to the tubes?  Forgive my ignorance but I am only aware of his early favorite (modded Brooks 12A  2A3 PP of 10W. or so), and latter the various pro SS amps from Crown, BGW, etc.  

 

 

 

I'm sure he certainly had excess to any amp. at his disposal, yet when SET amps galore were so easily available he still made the call "What this country needs is a good 5 watt amplifier".   Why would he say such a thing if the SET was the ultimate circuit and at the same time so attainable?   Why would he only endorse the modded Brooks and not a SET?

 

 

 

I think we have somehow created our own “red herrings” that we are now chasing upstream.  In many of the articles where we have jumped to conclusions that Paul was promoting one type of amplifier topology over another, our conclusions appear to be incorrect and he is really expounding upon how well-engineered his Klipshorn speakers are.  When it comes to amplifiers, I believe that PWK was primarily pointing out a simple mathematical relationship and facing an economic reality of the times he lived.

 

After reviewing a multitude of evidence for which I have outlined a few key points in more detail below, I tend to hold the view that I don't think PWK can be used as an advocate of low powered SET amplifiers any more than he can be used as an advocate for mid-power solid state amplifiers.  Although, in one of the “Dope From Hope articles” he does state that “In a typical living room or small theater, our present all-horn systems offer concert-hall levels with a mere 10 watts peak input.”  There again, PWK specifically stated 10 watts, not 5 watts, and I believe his statement was a tribute to the engineering of the loudspeaker in that it could reproduce concert-level SPL with fairly low power (e.g., doing the math), not an endorsement of any specific amplifiers or amplifier topologies.

 

The simple fact of the matter was, is, and always will be, the Klipschorn speaker efficiency allows a person to use very low-powered amplifiers if that type of amplifier meets that person’s listening requirements, regardless of whether that choice is SET, SEP, Push-Pull, solid state, or otherwise; and as I have noted in other posts, the Klipschhorn will reveal very quickly if the amplifier sucks or the source sucks or both suck.

 

After spending a very substantial amount of time revisiting the “Dope From Hope” articles and various other documentation (including the pages of “Klipschisms, quotes and anecdotes" attributed to PWK on the main website), I also could not substantiate that PWK explicitly voiced, or had written the quote often attributed to him that "What this country needs is a good 5 watt amplifier."  Without specific credible evidence, especially given that PWK was looking for concert-level reproduction of 115dB SPL at the listening position, I'm now wondering if the quote is a type of urban legend that has proliferated over the internet, similar to the Robert Hartley situation I describe below (e.g., in PWKs situation outlined below, 5 acoustic watts = 20 amplifier watts, not 5 amplifier watts).

 

Jim Hunter, just where are you when we need you?  

 

Since the written records appear to clearly show that PWK loved his push-pull 10 watt per channel Brook 12A amplifier, he may have actually been complaining that amplifiers of his time were not powerful enough, in addition to not being good enough. 

 

The written information appears to show that, in addition to PWK liking the Brook 12A amplifier at first, he then moved to a variety of mostly solid state amplifiers in the range of approximately 60 watts per channel.  I have also found references where he used a lot of different brands including Crown (D60) and BGW (model 100).

 

An interesting side note with the Klipschorn history in relation to the Brook amplifier is that Paul (and Brook) collaborated to squeeze more [power] from the 12A amplifier (a 2A3 push pull design) and developed modifications to address some bass deficiencies that were revealed by the Klipschorn speakers.  The modification subsequently became a factory mod available to optimize the amplifier to the Klipshorn and was given the catalogue number of “12A3-KI.”

 

I have also found that there are many other references in his literature where he recommended 20 watts per channel amplifiers as a minimum for Klipschorns.  Keeping in mind that one goal that PWK had often articulated in both verbal and written form, was that his loudspeakers were capable of reproducing concert-level sound of about 115dB at the listener's position, and here is one such reference.

 

"[''What size amplifier shall I buy?" This is really the first of two questions. The answer, applied to KLIPSCH speakers, would be a maximum of 100 watts (sine wave rating) per side. If a higher power is used, precautions may be needed to prevent speaker damage.  Crown suggests a one ampere fuse for each channel.

 

The second question, I think we can assume, is fishing for a realistic relation between sound pressure level and amplifier power.  Accept the figure that 115 dB peak sound level pressure at the listener's ear will be as loud as what you would hear at a live concert. (A sound level meter would read 103 dB at "maximum" swings, because a V.U. meter has a "delay" or "lag", and instantaneous peaks are about 13 dB higher than the meter reading peaks).

 

In a typical 4000 cubic foot listening room, this requires 40 peak amplifier watts to feed a group of high efficiency loudspeakers: assuming this to be 2-channel stereo, 20 peak watts per channel or 10 watts average sine wave power rating per side is required. For a low efficiency speaker (of the typical so-called air suspension type) over 100 times as much amplifier power would be necessary: that makes over one kilowatt of sine-wave rated power for each channel.]"

 

In a follow up "Dope From Hope" article PWK then went on to state that, "[back in the good old days of 10 and 20 watt amplifiers it was uncommon to experience loudspeaker failures. When 75 watts became common, occasional tweeter failures began to occur. Then with the advent of large solid-state amplifiers with their 240 instantaneous power peaks, tweeter failures became epidemic and woofers began to come apart at the compliance rings and voice coils began to tear loose from cones.]"

 

Another misnomer that I found was that PWK often referred to “acoustic watts” and invariably magazine writers (e.g., Robert Hartley), among others would drop the “acoustic” and just state watts, which was misleading and only perpetuated inaccuracies.

 

The following are PWK definitions published in a Dope From Hope article.

 

WATT

 

First of all a watt is a unit of power or rate of doing work, whether electrical, mechanical, thermal or acoustic. Equivalents are 0.738 foot pounds per second, 0.238 calories per second, or

 

w = e^2/z

 

Where w is watt, e^2 is electrical pressure or electromotive force in volts and z is electrical impedance in ohms.

 

The acoustic watt may be similarly expressed in terms of acoustic sound pressure p in dynes per square centimeter and the acoustic impedance of air which has been derived as the product of the air density times the velocity of sound p thus w = p^2/z.

 

When the sound pressure level is 100 dB, the sound power transmitted is 10^6 watt per square centimeter. (The 100 dB level is referred to zero dB = 0.000204 dynes per square centimeter: thus 100 dB = 20.4 dynes per square centimeter).

 

ACOUSTIC WATT

 

Translating the above numbers into something quickly useful, it turns out that a sound source radiating from a trihedral corner with a uniform polar pattern will be radiating one watt of power when the sound pressure measured at 4 feet is 118 decibels.

 

Essentially, it came down to PWK’s literature recommending 20 watt amplifiers as the minimum for Klipschorn loudspeakers.

 

In my reference to Robert Hartley, I’m referring to his article where he writes that “loudspeaker pioneer Paul Klipsch conducted a demonstration of live vs. reproduced sound with a symphony orchestra and his Klipschorn loudspeakers. His amplifier power: 5W. The Klipschorns are so sensitive (an astounding 105dB SPL, 1W/1m) that they will produce very high volumes with very little amplifier power. Klipsch was attempting to show that his loudspeakers could closely mimic the tonal quality and loudness of a full symphony orchestra.”

 

If anyone has been following the various posts in the “high power amplifier” thread, I would have a hard time believing that someone could still conclude that a 5 watt amplifier would attain that type of concert level SPL in a theater where a symphony orchestra was playing.

 

The ad, written by PWK, talks about a symphony orchestra and 5 watts; however, he is not talking about a nominal 5 watts, but is talking about 5 acoustic watts as he has defined it above.  To achieve 5 acoustic watts in the room PWK is talking about, he has two Klipschorns and a Belle and each channel connected to 20 watt amplifiers.  Once I crunched the math, it became pretty obvious what happened in that Hartley dropped the word "acoustic."

 

Essentially, there you have it in that it seems that PWK has outlined various situations that appear to indicate that for 2-channel stereo, 20 peak watts per channel or 10 watts average sine wave power would cover the concert level SPL THAT he had strived to achieve.

 

.

 

 

 

Great post! 

[tube fanatic]

The fundamental problem with this discussion is that it assumes everyone is interested in achieving a 115db listening level in their room.  Firstly, in my sphere of acquaintances that is totally unrealistic (except for "the guy down the road") as no one wants to even remotely approach that.  Secondly, there's a big difference in experiencing such a level between our listening rooms and, say, Carnegie Hall.  I don't care how loudly a system can play, there's no way to duplicate the acoustical environment of a concert theater.  As to the comments about SETs sounding bad because of high distortion, that's certainly not true if they are used for their intended purpose, which is typically lower level listening.  For example, I'm playing around with a design for a forthcoming flea-power SET.  Its worst case 2nd harmonic distortion will occur with a speaker impedance drop to 4 ohms (from the 8 ohm tap) at which it can deliver 1.6 watts at 5.5%.  That same amp, when delivering approx. 300 milliwatts, shows 2nd harmonic distortion of only 0.8% which is better than many highly regarded push-pull designs.  My typical listening levels, and those of most of the Klipsch speaker owners I know, require between 50 and 100 milliwatts which brings the distortion down to the extremely low levels of the best SS amps.  And, I also have more than enough headroom to match that of any recording which I choose to play.  So, we need to get some context here in regard to what Dave (the OP) wants to achieve in his system.  I will tell you that as a custom designer I always start with the speakers and work backwards.  It's the only way to design an amplifier output stage which will satisfy the requirements.  The same applies to an amp which one purchases.  If you need a certain amount of clean power to achieve a certain level, then buy what you need.  The analogy that my cousin, a retired auto mechanic, always used, "you don't need to drop a Chrysler Hemi into a Duster if all you're doing is driving down Main Street at 25 mph," applies here as well.

Maynard

[CECAA850]

Lets all stay on topic.  There's a lot of great info in this thread and it needs to stay open.  Personal accusations or attacks by anyone will shut it down and we're currently teetering on the precipice.

[2Bmusic]

Lets all stay on topic.  There's a lot of great info in this thread and it needs to stay open.  Personal accusations or attacks by anyone will shut it down and we're currently teetering on the precipice.

Yes, please do not mess up my thread!

 

Besides I am looking for info not arguments.

[2Bmusic]

with regard to the above statements.  I say this with humility and hope for finding the truth...

 

I played Bella Flecks "FLIGHT OF THE COSMIC HIPPO".   This work will tax all equipment that tries to reproduce it.  In playing that music I can tell you with full certainty the following: 

 

When I say best sound possible, I am taking about music that sounds as close to original as possible.

 

My big ben 4 ~6 watt SET did not have enough to power to reproduce bass notes as well as a 25 watt p/p amp.  This makes sense big time.

 

........ the Khorn with its incredible dynamic range will "most likely"  ( maybe---- maybe not)  perform best with bi-amp.  

 

An SET for top side and SS for lows.....  or some equipment similar.   As for how this will sound, one would have to try it and see. 

 

         *****    THE SCIENTIFIC METHOD******

 WITH REGARD TO All the above talk about this and that.  WELL it is important to compare apples to apples.  What I mean is that one should take one song that has the full spectrum of frequencies ( 20 hertz to 20,000 hertz).  This song should be played through all equipment in question.  Why because audio engineers will vary settings as recording or mastering is being done.    DOESN'T it make sense to compare you know values? 

Edited April 8, 2016 by 2Bmusic

[NOSValves]

 

 

My big ben 4 ~6 watt SET did not have enough to power to reproduce bass notes as well as a 25 watt p/p amp.   

 

 

The curiosity is killing me. What is this 25 watt push pull EL84 amplifier? 

[Fjd]

On ‎4‎/‎8‎/‎2016 at 10:26 AM, 2Bmusic said:

with regard to the above statements.  I say this with humility and hope for finding the truth...

 

I played Bella Flecks "FLIGHT OF THE COSMIC HIPPO".   This work will tax all equipment that tries to reproduce it.  In playing that music I can tell you with full certainty the following: 

 

When I say best sound possible, I am taking about music that sounds as close to original as possible.

 

My big ben 4 ~6 watt SET did not have enough to power to reproduce bass notes as well as a 25 watt p/p amp.  This makes sense big time.

 

........ the Khorn with its incredible dynamic range will "most likely"  ( maybe---- maybe not)  perform best with bi-amp.  

 

An SET for top side and SS for lows.....  or some equipment similar.   As for how this will sound, one would have to try it and see. 

 

         *****    THE SCIENTIFIC METHOD******

 WITH REGARD TO All the above talk about this and that.  WELL it is important to compare apples to apples.  What I mean is that one should take one song that has the full spectrum of frequencies ( 20 hertz to 20,000 hertz).  This song should be played through all equipment in question.  Why because audio engineers will vary settings as recording or mastering is being done.    DOESN'T it make sense to compare you know values? 

 

 

 

Agreed, that a comparison on an "apple to apple" basis appears to make sense and stress both amplifiers in relation to how you like to listen in order to evaluate how they perform in relation to your listening habits.  However, this information now begs the question regarding how precise did you match the gain of each amplifier in your comparison?  

 

In my experience, some people tend to forget about "level matching" or "gain matching" when comparing amplifiers.  Even very slight differences in gain between amplifiers can be audible as I have found that precise level matching can be more critical than most even realize.  In certain situations a 1 dB difference can change a person's perception of an amplifier. 

 

For example, in certain listening rooms that tend to allow a speaker to "bloom" with reflective surfaces and very little absorption, a person could fairly easily detect a 1 dB difference in output level between amplifiers.  From another perspective, even with "gain matching" the lower powered single-ended amplifiers are working much harder where the single-ended amplifier is being run much closer to its maximum power ratings, which tends to mean that they are distorting more. The lower the power output of the amp, the more many people make them work extremely close to the amplifier limits and the more it will be distorting.

 

I believe that it has been fairly well documented by Nelson Pass and others that distortion of the 2nd harmonics variety, in general, tend to be very pleasing to the ear and the correlation has often been made that perhaps the listeners that love the 'blooming' midrange are actually loving the additional harmonic distortions caused by running the amp fairly hard relative to its power output.

 

Given the above, on a side note, as I've posted multiple times in this thread and other threads, there is nothing wrong with liking that, it is a persons personal taste after all.  I don't make it a habit to judge another person's personal taste and I sure hope that readers do not jump to unfounded conclusions reading my posts.  Those that take the time to read my posts and in some instances ask clarifying questions, know that I look at the music listening experience from a "situational" standpoint  and try to match a system to the mood of the environment; and have run a very large variety of amplifiers and have a fairly large stable of single-ended direct heated triode and single ended pentode amplifiers too.

 

In addition, since you brought up scientific methods, I firmly believe that the ear (even an “untrained” ear) can detect very small differences that seem very inconsequential on the surface; and I certainly cannot find fault with those that just use their ears and go with what provides the listening experience they are looking for.  However, from another perspective, my point regarding gain matching is that although the ear can detect very small differences, the brain may not exactly know what aspect of the music reproduction chain to attribute the difference.  

 

In general, when gain levels are different, it seems that many will tend to conclude that louder music, even if it's just slightly louder, will almost always sounds better to them than the quieter music. 

 

Now for those reading the thread that may decide to go the measurement route and do some gain matching for amplifier comparison, I would recommend using a volt meter that will measure down to 0.001 volt AC if possible.

 

I have gone back and forth in my mind, while playing the relevant test tones, which is the best place to measure.  For example, if measuring at the output of the power amp or if the measurements should be made at the speaker terminals. 

 

I've been thinking that maybe both places, which will allow you to understand the voltage drop for each speaker wire or channel.  For example, when you measure at the amplifier, in most instances you will find it to be slightly more voltage as the speaker wire resistance is not part of the measurement.  Now if you decide to measure the voltage at the speaker connections, in most cases you will find it to be slightly less voltage as compared to the measurement at amplifier connections due to a certain amount of voltage drop across the speaker wire.  

 

Now with the test tones playing over the two signal paths, I would shoot for a level match within about 1% or a level match of about 0.1 dB difference.

 

Although, given what I suspect to be the perceived difficulty of the above, I cannot necessarily find fault with those that just use their ears and forego the measurements, go with what provides the listening experience they are looking for, and attribute the difference to whatever the brain tells them too.

[Mallette]

It is quite obvious to everyone that you have Moderator buddies who let you do what no one other business owner can do.

 

If you have examples that prove your point, make them.  Yes, Craig has crossed the line at times and been duly warned, and he's responded positively.  I can assure you that Craig doesn't feel like he has any "moderator buddies."  Take your issues with us up personally or with Chad, as you see fit. 

 

Dave

[Ski Bum]

Hmm.  Some semantic pot holes have appeared in the road.

 

Distortion is not necessarily bad, and often results in an interpretation of being "more realistic" by the user.  By objective measures, Maynard's amp with 5% 2nd harmonic undoubtedly measures worse than 2Bmusic's Yamaha in a multitude of ways.  So on a certain level I find it impossible to regard single ended tube amps as simply "amplifiers" as they're adding something that wasn't in the recording.  That's just a fact.  (And yes, I realize that 5% 2nd harmonic is consonant, largely masked by the fundamental, and basically inaudible.)  It's also a fact that many who have experienced both prefer the "process" that the tubes apply. 

 

 

When I say best sound possible, I am taking about music that sounds as close to original as possible.

   

 

Some would posit that the magic of the original performance was bastardized the moment the sound was captured by the mics, in which case a little tube amp processing embellishment on playback is a-ok.  Accuracy to the original is a laudable goal, but never achieved.  If that's the goal, then go by the book: only use amps with low distortion, low output impedance, and enough power that clipping is never an issue, and enjoy the resulting dry, clinical sound.  Or try one of Maynards designs, which definitely add a bit of wetness and real-life-resembling spatial qualities (IME only SE amps do this trickery).

 

Bi-amping may work, provided the amps don't have too much divergence in their sonic character.  A lyrical sounding SET up top may audibly clash with a tight, dry ss amp on the woofs.  That was my experience, at least.  The puny amps weren't as strong down low, but there was a certain roundness of tone from the tubes that was lost with ss.  Another experience I've had is that the small tube amps seem to be able to handle eq (bass boost) rather well, with less handicapping of overall power than I expected.  Have you tried to simply eq your bass?

[Fjd]

with regard to the above statements.  I say this with humility and hope for finding the truth...

 

I played Bella Flecks "FLIGHT OF THE COSMIC HIPPO".   This work will tax all equipment that tries to reproduce it.  In playing that music I can tell you with full certainty the following: 

 

When I say best sound possible, I am taking about music that sounds as close to original as possible.

 

My big ben 4 ~6 watt SET did not have enough to power to reproduce bass notes as well as a 25 watt p/p amp.  This makes sense big time.

 

........ the Khorn with its incredible dynamic range will "most likely"  ( maybe---- maybe not)  perform best with bi-amp.  

 

An SET for top side and SS for lows.....  or some equipment similar.   As for how this will sound, one would have to try it and see. 

 

         *****    THE SCIENTIFIC METHOD******

 WITH REGARD TO All the above talk about this and that.  WELL it is important to compare apples to apples.  What I mean is that one should take one song that has the full spectrum of frequencies ( 20 hertz to 20,000 hertz).  This song should be played through all equipment in question.  Why because audio engineers will vary settings as recording or mastering is being done.    DOESN'T it make sense to compare you know values? 

 

 

 

Here is a combination that I found to be a fun experiment.  The First Watt F4 (I would suggest reading the manual Nelson Pass has posted to the First Watt web site) in a "bi-amp" setup and drive it with a single-ended tube amplifier as Nelson Pass describes in the schematic below (and his operating manual) where the single-ended tube amplifier directly drives the mid/tweeter and drives the F4 that in turn drives the woofers. 

 

A single F4 will give 25 watts (50 watt peak) per channel into 8 ohms and 40 watts into 4 ohms. However, wired as a mono block the F4 will give 100 watts.  The First Watt F4 has zero voltage gain, which eliminates the need to "gain match" with the single-ended amplifier. Essentially, one way to think about the F4 is having a "component" approach to your voltage gain and your current gain.  Basically, the F4 can be thought of as a refined power follower, it will essentially push the same voltage out that you send into it, but it will feed much more current through the load than the single-ended amplifier, if, or when, needed.

 

I see this same concept of tube for voltage gain and solid state (usually mosfets) for current used in some of the high-end headphone amps too. 

 

As I mentioned, in another set-up that I experiment with, I essentially use my DHT SET amplifier as the "voltage gain stage" directly into the F4 and try to maximize the aspect that the F4 is such a simple Push-Pull circuit with no negative feedback, very low distortion levels and only a miniscule 50uV noise level.  In this regard a lot of the characteristics of the DHT SET amp that I find very favorable will come through. I like to think of it kind of like a "SET on steroids" in some ways, but also noting that it looses only some very small aspect of that intimacy that DHT SET can provide in those near-field lower-level listening sessions.

 

On an important side note, there are various implementations of "adaptors" out there as the DHT SET output will need to be adapted to the RCA input of the F4.  Also, due to the F4's high input impedance (47,000 ohms), a resistor (~ 20 ohm, 5 watt resistor, but some have used anywhere from about 15 ohm - 22 ohm depending on how they like the sound) is needed across the SET outputs since the SET only "sees" the F4 and not the speakers.  On DHT SET amps with multiple taps (i.e. 4, 8 or 16 ohm) there seems to be some diversity on which tap sounds best; however, I suspect that is more related to system synergies.

 

The catch?  The F4 has reached the end of the 100 unit run that Nelson Pass had set and is no longer available new leaving the option of watching the used secondary market or building a DIY clone.  If you find this interesting, the F4 is well-documented on the DIY Audio site with build guides and a lot of troubleshooting information.  In addition, the DIY store stocks most of the hard-to-find parts.

 

 

Edited April 8, 2016 by Fjd

[NOSValves]

 

 

From the master,

 

 "What this country needs is a good 5 watt amplifier" (Paul Klipsch).

 

Since the beginning of amplification single ended triodes have been acclaimed as the ultimate in sound reproduction. If the low 5 or 6 watt SET's are not good enough for our 100db speakers exactly what kind of speaker are they good for. The highly acclaimed SS designer Nelson Pass has devoted a considerable amount of his time trying to duplicate the single ended triode tube sound with SS devices. Audiophile reviewers worldwide still acclaim SET as the ultimate in sound reproduction and all other forms of amplification is judge on how it compares to the SET. 

 

There are still people that believe OJ did not do it or the world is not round. It does no good to argue with them.

 

You have to be the judge of what sounds good to you and buy what you think is best. What I have just said is just cold hard facts. What anyone hears is not reality but our own interpretation of it. When someone works hard for their money they should be able to spend it as they choose to not by what anyone else says. 

 

Since you bring up PWK, could you tell me some of the SET amps he used?   Or for that matter any tube amps that he used later in his life when SS became a viable option to the tubes?  Forgive my ignorance but I am only aware of his early favorite (modded Brooks 12A  2A3 PP of 10W. or so), and latter the various pro SS amps from Crown, BGW, etc.  

 

 

 

I'm sure he certainly had excess to any amp. at his disposal, yet when SET amps galore were so easily available he still made the call "What this country needs is a good 5 watt amplifier".   Why would he say such a thing if the SET was the ultimate circuit and at the same time so attainable?   Why would he only endorse the modded Brooks and not a SET?

 

 

 

I think we have somehow created our own “red herrings” that we are now chasing upstream.  In many of the articles where we have jumped to conclusions that Paul was promoting one type of amplifier topology over another, our conclusions appear to be incorrect and he is really expounding upon how well-engineered his Klipshorn speakers are.  When it comes to amplifiers, I believe that PWK was primarily pointing out a simple mathematical relationship and facing an economic reality of the times he lived.

 

After reviewing a multitude of evidence for which I have outlined a few key points in more detail below, I tend to hold the view that I don't think PWK can be used as an advocate of low powered SET amplifiers any more than he can be used as an advocate for mid-power solid state amplifiers.  Although, in one of the “Dope From Hope articles” he does state that “In a typical living room or small theater, our present all-horn systems offer concert-hall levels with a mere 10 watts peak input.”  There again, PWK specifically stated 10 watts, not 5 watts, and I believe his statement was a tribute to the engineering of the loudspeaker in that it could reproduce concert-level SPL with fairly low power (e.g., doing the math), not an endorsement of any specific amplifiers or amplifier topologies.

 

The simple fact of the matter was, is, and always will be, the Klipschorn speaker efficiency allows a person to use very low-powered amplifiers if that type of amplifier meets that person’s listening requirements, regardless of whether that choice is SET, SEP, Push-Pull, solid state, or otherwise; and as I have noted in other posts, the Klipschhorn will reveal very quickly if the amplifier sucks or the source sucks or both suck.

 

After spending a very substantial amount of time revisiting the “Dope From Hope” articles and various other documentation (including the pages of “Klipschisms, quotes and anecdotes" attributed to PWK on the main website), I also could not substantiate that PWK explicitly voiced, or had written the quote often attributed to him that "What this country needs is a good 5 watt amplifier."  Without specific credible evidence, especially given that PWK was looking for concert-level reproduction of 115dB SPL at the listening position, I'm now wondering if the quote is a type of urban legend that has proliferated over the internet, similar to the Robert Hartley situation I describe below (e.g., in PWKs situation outlined below, 5 acoustic watts = 20 amplifier watts, not 5 amplifier watts).

 

Jim Hunter, just where are you when we need you?  

 

Since the written records appear to clearly show that PWK loved his push-pull 10 watt per channel Brook 12A amplifier, he may have actually been complaining that amplifiers of his time were not powerful enough, in addition to not being good enough. 

 

The written information appears to show that, in addition to PWK liking the Brook 12A amplifier at first, he then moved to a variety of mostly solid state amplifiers in the range of approximately 60 watts per channel.  I have also found references where he used a lot of different brands including Crown (D60) and BGW (model 100).

 

An interesting side note with the Klipschorn history in relation to the Brook amplifier is that Paul (and Brook) collaborated to squeeze more [power] from the 12A amplifier (a 2A3 push pull design) and developed modifications to address some bass deficiencies that were revealed by the Klipschorn speakers.  The modification subsequently became a factory mod available to optimize the amplifier to the Klipshorn and was given the catalogue number of “12A3-KI.”

 

I have also found that there are many other references in his literature where he recommended 20 watts per channel amplifiers as a minimum for Klipschorns.  Keeping in mind that one goal that PWK had often articulated in both verbal and written form, was that his loudspeakers were capable of reproducing concert-level sound of about 115dB at the listener's position, and here is one such reference.

 

"[''What size amplifier shall I buy?" This is really the first of two questions. The answer, applied to KLIPSCH speakers, would be a maximum of 100 watts (sine wave rating) per side. If a higher power is used, precautions may be needed to prevent speaker damage.  Crown suggests a one ampere fuse for each channel.

 

The second question, I think we can assume, is fishing for a realistic relation between sound pressure level and amplifier power.  Accept the figure that 115 dB peak sound level pressure at the listener's ear will be as loud as what you would hear at a live concert. (A sound level meter would read 103 dB at "maximum" swings, because a V.U. meter has a "delay" or "lag", and instantaneous peaks are about 13 dB higher than the meter reading peaks).

 

In a typical 4000 cubic foot listening room, this requires 40 peak amplifier watts to feed a group of high efficiency loudspeakers: assuming this to be 2-channel stereo, 20 peak watts per channel or 10 watts average sine wave power rating per side is required. For a low efficiency speaker (of the typical so-called air suspension type) over 100 times as much amplifier power would be necessary: that makes over one kilowatt of sine-wave rated power for each channel.]"

 

In a follow up "Dope From Hope" article PWK then went on to state that, "[back in the good old days of 10 and 20 watt amplifiers it was uncommon to experience loudspeaker failures. When 75 watts became common, occasional tweeter failures began to occur. Then with the advent of large solid-state amplifiers with their 240 instantaneous power peaks, tweeter failures became epidemic and woofers began to come apart at the compliance rings and voice coils began to tear loose from cones.]"

 

Another misnomer that I found was that PWK often referred to “acoustic watts” and invariably magazine writers (e.g., Robert Hartley), among others would drop the “acoustic” and just state watts, which was misleading and only perpetuated inaccuracies.

 

The following are PWK definitions published in a Dope From Hope article.

 

WATT

 

First of all a watt is a unit of power or rate of doing work, whether electrical, mechanical, thermal or acoustic. Equivalents are 0.738 foot pounds per second, 0.238 calories per second, or

 

w = e^2/z

 

Where w is watt, e^2 is electrical pressure or electromotive force in volts and z is electrical impedance in ohms.

 

The acoustic watt may be similarly expressed in terms of acoustic sound pressure p in dynes per square centimeter and the acoustic impedance of air which has been derived as the product of the air density times the velocity of sound p thus w = p^2/z.

 

When the sound pressure level is 100 dB, the sound power transmitted is 10^6 watt per square centimeter. (The 100 dB level is referred to zero dB = 0.000204 dynes per square centimeter: thus 100 dB = 20.4 dynes per square centimeter).

 

ACOUSTIC WATT

 

Translating the above numbers into something quickly useful, it turns out that a sound source radiating from a trihedral corner with a uniform polar pattern will be radiating one watt of power when the sound pressure measured at 4 feet is 118 decibels.

 

Essentially, it came down to PWK’s literature recommending 20 watt amplifiers as the minimum for Klipschorn loudspeakers.

 

In my reference to Robert Hartley, I’m referring to his article where he writes that “loudspeaker pioneer Paul Klipsch conducted a demonstration of live vs. reproduced sound with a symphony orchestra and his Klipschorn loudspeakers. His amplifier power: 5W. The Klipschorns are so sensitive (an astounding 105dB SPL, 1W/1m) that they will produce very high volumes with very little amplifier power. Klipsch was attempting to show that his loudspeakers could closely mimic the tonal quality and loudness of a full symphony orchestra.”

 

If anyone has been following the various posts in the “high power amplifier” thread, I would have a hard time believing that someone could still conclude that a 5 watt amplifier would attain that type of concert level SPL in a theater where a symphony orchestra was playing.

 

The ad, written by PWK, talks about a symphony orchestra and 5 watts; however, he is not talking about a nominal 5 watts, but is talking about 5 acoustic watts as he has defined it above.  To achieve 5 acoustic watts in the room PWK is talking about, he has two Klipschorns and a Belle and each channel connected to 20 watt amplifiers.  Once I crunched the math, it became pretty obvious what happened in that Hartley dropped the word "acoustic."

 

Essentially, there you have it in that it seems that PWK has outlined various situations that appear to indicate that for 2-channel stereo, 20 peak watts per channel or 10 watts average sine wave power would cover the concert level SPL THAT he had strived to achieve.

 

.

 

 

 

Really really great and sensible post. I commend you on your time spent doing research! 

Edited April 8, 2016 by NOSValves

[dtel's wife]

It is quite obvious to everyone that you have Moderator buddies who let you do what no one other business owner can do.

 

If you have examples that prove your point, make them.  Yes, Craig has crossed the line at times and been duly warned, and he's responded positively.  I can assure you that Craig doesn't feel like he has any "moderator buddies."  Take your issues with us up personally or with Chad, as you see fit. 

 

Dave

I agree with Dave completely on this. I assure you that Craig has been duly warned when he crosses the line. You can pm any of us or Chad with issues you may have with our moderating.

[richieb]

I do not preach the virtues of single ended but know thats the sonic presentation I favor. I've had more amps through my rig than I care to mention which always get sold for - another single ended. I do not and do not intend to listen at concert levels so mid to hi power is not a requirement with my KHorns. And if I do I always keep a little extra power amp in reserve. Currently enjoying 5 watts of tube rectified EL84 and if my offer is accepted monoblock 2a3 will be on there way.

[dtel's wife]

fjd that post was incredible!!! You did a great job on that one!!