Can we address the low power amp again --?

[J M O N]

I used to have Wright Sound 2A3 monos putting out 3.5 watts per channel.  I could get much higher volume levels with Klipschorns than I thought possible with 3.5 watts.  When I turned it up about as loud as it could reasonably play, I could go outside to the street and hear the music playing with all the doors and windows closed.  They met my needs for about 98% of the volume levels I typically listened to.  The other 2% of the time, a higher powered amp would be needed.

 

Now, they can play "loud" but not "crazy loud."  If you want to play it extremely loud and impress your friends, then these are probably not the right kind of amplifiers for you.

 

One thing I do remember about them is that they sounded so good that I no longer had that desire to keep turning up the volume to make them sound better.  They are wonderful amplifiers and I kinda regret selling them.

[mikebse2a3]

One thing I do remember about them is that they sounded so good that I no longer had that desire to keep turning up the volume to make them sound better. They are wonderful amplifiers and I kinda regret selling them.

 

Great observation..!

 

One of the best indicators that a system isn't optimized is when one keeps turning up the volume trying to make the sound reproduction better.

 

 

miketn

[Don Richard]

One thing I do remember about them is that they sounded so good that I no longer had that desire to keep turning up the volume to make them sound better. They are wonderful amplifiers and I kinda regret selling them.

 

Have you considered the possibility that they started to sound bad when turned up so you learned to play them in the range where the distortion was acceptable to you?

 

 

 

One of the best indicators that a system isn't optimized is when one keeps turning up the volume trying to make the sound reproduction better.

 

I disagree. I say that a system (Electronics, Speakers, and ROOM) should sound "good" at all volume levels, not just when played at low levels or just when played loudly. Some live music is performed at a relatively quiet level, other live music is very dynamic. A proper system is more versatile and can do both without compromise.

Edited March 28, 2015 by Don Richard

[erik2A3]

Listening to a live musical event (regardless of the sound pressure levels) is significantly different from reproducing a recording. What Mike is saying is arguably correct in a number of ways. One thing that happens at lower vołume control rotations has really less to do with the interface between amplifiers and speakers than it does with an upstream component -- namely the potentiometer on either a preamplifier (as in either an active linestage or passive, in-line attenuator).

To state this in simple terms, a potentiometer is a variable resistor which changes in value according to the position of the wiper on its carbon element (or fixed value of resistance on a stepped attenuator built on varying levels of fixed resistance). At low volume settings in general, and in cases where the output impedance of the preamp may not be well-suited to the input impedance of the amplifier in particular, the effects that a potentiometer can have on the overall sound quality of a system can be remarkable. In cases such as this (poor impedance matching between components), lower volume control settings, because of the changes in resistance within the potentiometer, can result in a quality of sound lacking in 'presence' and immediacy. The system's overall high frequency response is compromised and music sounds dull and devoid of clean and sharp high frequency transient response.

I wholeheartedly agree with Mike. If a signal chain is already compromised by inadequate matching between the components within that chain, the seemingly benign act of turning down the volume can have a marked influence on the perceived sound. In fact, some designers of musical instrument amplifiers include a very simple form of 'EQ' to ameliorate potentiometer effects on sound at quiet vołume settings: it involves the installation of a small value capacitor (picofarads) on the potentiometer which functions as high pass filter and allows the transmission of high frequency information that would otherwise be choked off -- and which in turns leads to poor low-vołume sound reproduction. When the volume is turned up (again in simplified terms), the electrical characteristics of the potentiometer are again altered, but this time in a manner that benefits the overall reproduction. Moreover, the high pass capacitor that may have been installed on the volume control (which can be switched in and out of the circuit if so desired) to improve the sound at low volume becomes essentially unseen; its effects come into play only at very low vołume settings.

There are many other examples.

[mikebse2a3]

 

One thing I do remember about them is that they sounded so good that I no longer had that desire to keep turning up the volume to make them sound better. They are wonderful amplifiers and I kinda regret selling them.

 

Have you considered the possibility that they started to sound bad when turned up so you learned to play them in the range where the distortion was acceptable to you?

 

 

Did you consider that JMON found an amplifier that was capable of reproducing a recording at it's most realistic point in volume as well as other reproduction qualities and the other amplifier was not capable of that quality regardless of volume level even if it could play louder.

 

 

 

 

 

 

 

 

One of the best indicators that a system isn't optimized is when one keeps turning up the volume trying to make the sound reproduction better.

 

I disagree. I say that a system (Electronics, Speakers, and ROOM) should sound "good" at all volume levels, not just when played at low levels or just when played loudly. Some live music is performed at a relatively quiet level, other live music is very dynamic. A proper system is more versatile and can do both without compromise.

 

 

I agree with your statement " a system (Electronics, Speakers, and ROOM) should sound "good" at all volume levels, not just when played at low levels or just when played loudly"  but that isn't what I was making an observation about.

 

 

 IMO there is often displayed an audiophile tendency to turn the volume up to fix certain distortions in reproduction that gets triggered and when this doesn't help listener fatigue often follows.

 

miketn

Edited March 28, 2015 by mikebse2a3

[erik2A3]

There may be a reason that someone, whether an audiophile or not, might have an inclination to turn the volume up. Doing so may in fact mildly improve an already compromised or inadequately matched chain of components, but ultimately will not change the overall fact that certain elements in the signal chain simply don't work well together.

That systems should sound good at any vołume seems to me fairly obvious and is of course a desireble trait, but we all are accepting varying degrees of compromise, like it or not. Electrolytic coupling capacitors in source components, output transformers for impedance matching between power tubes and loudspeaker voice coils (OPTs being one of those 'compromises' that led some equipment designers to create tube amps that don't require them), lossy potentiometers (why some designers use transformer based attenuators), and so on. Some consider passive crossover networks, and those in particular that employ myriad circuits for impedance equalization (zobel -- which I can't stand), notch filters, resonant peak filters, etc. to be severely detrimental to vivid music reproduction and sources of phase distortion, and so on, and so refuse to listen to any speaker that consists of anything more than a wide-band, crossoverless transducer loaded in a horn loaded enclosure the size of a refrigerator -- which in and of itself is yet another source of distortion, and in fact happens to be a compromise of choice for me.

[erik2A3]

Even in cases where components are ideally matched one is still faced with compromises associated with not only the listening room, but one's own day to day human inconsistency and variability. How many times right here on this forum have I read where someone (very likely including myself) declare how amazing their system sounded one day, only to make a complete about face on another occasion and subsequently decide to sell everything and start from scratch?

[Don Richard]

Listening to a live musical event (regardless of the sound pressure levels) is significantly different from reproducing a recording. What Mike is saying is arguably correct in a number of ways. One thing that happens at lower vołume control rotations has really less to do with the interface between amplifiers and speakers than it does with an upstream component -- namely the potentiometer on either a preamplifier (as in either an active linestage or passive, in-line attenuator). To state this in simple terms, a potentiometer is a variable resistor which changes in value according to the position of the wiper on its carbon element (or fixed value of resistance on a stepped attenuator built on varying levels of fixed resistance). At low volume settings in general, and in cases where the output impedance of the preamp may not be well-suited to the input impedance of the amplifier in particular, the effects that a potentiometer can have on the overall sound quality of a system can be remarkable. In cases such as this (poor impedance matching between components), lower volume control settings, because of the changes in resistance within the potentiometer, can result in a quality of sound lacking in 'presence' and immediacy. The system's overall high frequency response is compromised and music sounds dull and devoid of clean and sharp high frequency transient response.

 

It seems to me that if the equipment were properly designed, and/or matched, in the first place none of what you wrote about would be happening. A properly designed buffer stage would eliminate such interactions you have described.

[Don Richard]

I agree with your statement " a system (Electronics, Speakers, and ROOM) should sound "good" at all volume levels, not just when played at low levels or just when played loudly" but that isn't what I was making an observation about. IMO there is often displayed an audiophile tendency to turn the volume up to fix certain distortions in reproduction that gets triggered and when this doesn't help listener fatigue often follows.

 

I was making an observation that when the source, the preamp, and the power amp interfaces work well together, when the power amp to speaker interface works well together, and when the speaker to room interface works well together, the likelihood of audible issues will be diminished. Some audiophiles apparently don't have the skills to do the matching on their own, and don't have the cash available to hire someone, such as a qualified individual who works at a high end audio store, to spec and set up the system for them.

 

It seems that today people get on the Interweb, read the opinions of people who may not know any more than they do, and shop price. Then they wind up with a mismatched system of questionable quality. They become dissatisfied which leads to a merry go round of cable purchases, selling of components they bought, and the purchasing of different equipment. These rumor-based purchases may not be any better than what they just sold. How sad.

[Don Richard]

Even in cases where components are ideally matched one is still faced with compromises associated with not only the listening room, but one's own day to day human inconsistency and variability. How many times right here on this forum have I read where someone (very likely including myself) declare how amazing their system sounded one day, only to make a complete about face on another occasion and subsequently decide to sell everything and start from scratch?

 

They might have heard something that sounded better, such as actual live music, that led it their dissatisfaction. I don't believe it is possible to exactly reproduce what someone heard live in a home setting, but some systems do a better job than other systems, and get pretty close to the live experience.

[Deang]

One of the best indicators that a system isn't optimized is when one keeps turning up the volume trying to make the sound reproduction better.

 

That's true, but only to a point. Part of the "optimization" equation is that people typically listen at a volumes that recreate the "live" experience. Now, that varies depending on the type of music they like. To experience a sense of realism, sometimes means pushing things up a bit. As a bit of a headbanger myself, I found the Wright's to be one of the most disappointing experiences I ever had -- just terrible. I thought the sound was dry and the peaks were clearly being clipped with very little effort on my part with the attenuator. Paul "Parrot" was over for a visit, and I'll never forget his face as we put on one of his favorite symphonic works and turned it up a bit. He looks over at me and says, "That's it? That's what all this SET nonsense is about? How can anyone possibly listen to that?".

 

Someone earlier in this thread mentioned that the only way to know whether or not something will work for you is to try it, and I totally agree with them.

[J M O N]

 

One thing I do remember about them is that they sounded so good that I no longer had that desire to keep turning up the volume to make them sound better. They are wonderful amplifiers and I kinda regret selling them.

 

Have you considered the possibility that they started to sound bad when turned up so you learned to play them in the range where the distortion was acceptable to you?

 

 

That definitely wasn't the case.  This occurred at very moderate listening levels where much higher volume levels were achievable with still great sound.  I was even able to achieve very nice sound at very low levels during late night listening sessions when others were asleep.

[J M O N]

I disagree. I say that a system (Electronics, Speakers, and ROOM) should sound "good" at all volume levels, not just when played at low levels or just when played loudly. Some live music is performed at a relatively quiet level, other live music is very dynamic. A proper system is more versatile and can do both without compromise.

 

 

I believe I was at that point with the exception of extremely loud levels.  It really sounded great at all volume levels within the limits of 3.5 Watts into Khorns (which could still get fairly loud, and as mentioned would meet 98% of my volume needs).  It was the very first time that I had no desire to upgrade anything.  Somehow, I think that room was also a big factor even though I did nothing to it.

[J M O N]

Just to make my point clear, I did not intend to imply that my system sounded best at low volumes.  It also sounded very good at higher volumes within the limitations of 3.5 Watts.

 

Even in cases where components are ideally matched one is still faced with compromises associated with not only the listening room, but one's own day to day human inconsistency and variability. How many times right here on this forum have I read where someone (very likely including myself) declare how amazing their system sounded one day, only to make a complete about face on another occasion and subsequently decide to sell everything and start from scratch?

 

I have gone through that exact same scenario many, many times -- one day my system sounds fantastic the very next day I'm disappointed.   The thing that amazed me with the system of this discussion is that never, ever happened.  Every single freaking time I turned it on, it made beautiful music!  I was ecstatic.  And it's important emphasize the point that it made beautiful music -- it was MUSICAL! I started listening to (end thoroughly enjoying) The MUSIC, instead of listening to the system and seeing how good or accurate the system sounded.  And isn't that the reason we're all into this stuff -- for the music?

 

Unfortunately for me, I've moved a few times since then and never have been able to recreate that same level of performance.  I'm sure that room had something to do with it -- it was a fairly large room and I have not had any room near its size since then.

[erik2A3]

Don -- that system components should ideally be matched to begin with is another (to me) rather obvious consideration. When I have built amplifiers and preamps in the past, I have built them to not only work well with each other, but within themselves. Just as one should consider inout and output impedance specs between components, one must in designing equipment consider the same thing between the different stages of a single component. Get that wrong and no amount of impedance buffering between components will remedy the problem. Nor will any amount of external impedance buffering fix the issue I mentioned above with potentiometers (particulalrly in the case of a passive in-line attenuator. We must also consider the power transfer function that takes place between amplifier and the reactive load of a loudspeaker. Certainly careful impedance matching between these two final components in the signal chain is a critical consideration, especially in the instance of using very low power triode amps, such as the Wright monoblocks mentioned above (by the way, Dean, I happened to work on the very pair you listened to shortly after you had them. I found that the connections related to the secondary winding on one of the amps had not only been reversed, but was not connected to the same secondary tap as that of its monoblock twin). That would explain at least some of what you were hearing, but of course would not address the overall disinterest I recall you and a number of other forum members had at the time for SETs in general. We tended to "visit" that topic often in the early years.

So, back to the amp/speaker relationship: impedance buffering is generally associated with line-level components, such as between an amplifier and preamp, CDP and preamp, and so on. If one has a situation where for example one happens to have speakers that present a difficult load (such as very low nominal impedance and/or low efficiency) and one happens to be attempting to drive them (just for example) with a single ended triode amp (keeping in mind that tube amps tend to have higher output impedance characteristics), then one is probably not going to be very satisfied with the result. Additionally, of that loudspeaker is a multi-driver system with a higher order passive dividing network, the problem will be compounded by the insertion losses associated with the crossover. That little amp will be puffing very hard to get virtually nowhere.

To that end and in my own case, the second pair of the two main speakers I have in my system have an efficiency of about 106 dB and a nominal impedance of 15 (not 16) ohms. They are extremely SET friendly, and the SPLs I can achieve with this combination is not only very loud (though I tend to listen at lower volumes), but very clean. It is a single very wide band driver that also does not rely on the potentially energy-sapping chokes and capacitors of a passive crossover. There is a problem with the particular drivers I'm using, however, which I knew existed before I bought them: they have a pretty wild impedance curve. The usual cure for this that many Lowther owners install a non-inductive swamping resistor across the voice coil in order to reflect a more even overall impedance to the amplifier. In other words, an impedance buffer. My personal problem with this is that while it may provide a more linear impedance plot, I simply don't care for the way it sounds. The drivers sound much more lively and seem to have greater overall all clarity and transient response without the swamping resistor. It's essentially the same thing some do with the autoformer on Klipsch Heritage networks for the same reason - to reflect a constant impedance to the amplifier. For some, that resistor is a compromise they would rather avoid; not all makers of after-market Klipsch crossovers approve of them.

I have mentioned impedance buffering many times on this forum, including back in the earlier years when I first visited this site (2002). Unity gain impedance buffering is fairly common, especially in the DIY community. Decware, along with their selections of tube equipment also offers something called a Z Box (the Z being the designation for impedance, just as L and R are for inductance and resistance).

Unfortunately, there are many problems related to component matching that an impedance buffer can't fix.