Question about amp compatibility with high sensitivity speakers

[Bfoura]

I sold a pair of B&W 803 D2’s and picked a pair of minty Chorus 1’s from a friend. I have mixed feelings about the move so far but have new Crites Crossovers and Ti diaphragms in hand and will be installing as soon as I can find a couple of hours. Perhaps that will improve detail and dynamics a bit. One of the reasons for picking up the Chorus is trying the high sensitivity speaker/lower watt amp combo that many enjoy.  I came across a post from Klipsch recommending to use no less than 80% and no more than twice the speaker’s continuous power rating. The RMS on the Chorus is 100 watts. I could be wrong but take that to mean use an amp no less than 80 watts and I more than 200 watts. The article talks about potentially damaging the speakers with too low or too much power. https://support.klipsch.com/hc/en-us/articles/360044125891-Choosing-the-Right-Receiver-Amplifier

 

I’m looking for feedback on actually using lower watt amps on Klipsch speakers. I’m using a 300 watt Levinson 532H but eager to try a lower power tube or a First Watt solid state as soon as possible. Thanks for chiming in. 

[garyrc]

Well lets see (I happen to  have a chart):

 

If  you want very realistic dynamics, and if your room has average liveness (I know, I know) and if you listen at about 13 feet away (or  less), you should be able to get the THX/Dolby instantaneous (1/4 second or less) peak level of 105 db at your ears above 80 Hz at 16 watts RMS with a bit of headroom to spare.  This assumes, that for bass below 80 Hz, you will have a powered subwoofer (although you may be too much of a purist, given your tastes as indicated in your post).  Horn subwoofers may be cleaner and faster than the typical.  The sub should be capable of 115 dB. 

 

If you don't use a sub, then you may want 10 dB more SPL available through the Chorus below 80 Hz -- although you may never use it -- requiring 160 watts.  

 

Now, a lot of people get away with 4 or 5 watts, or so, but I don't see how that can provide full dynamics.  If you don't want full dynamics, 5 watts would give you something like 100 dB at the MLP.  YMMV.

[henry4841]

One has to consider the way SS amplifiers clip vs tube amplifiers clipping. A tube amplifier can clip and one will never know it whereas when a SS amplifier clips it will sound terrible. I have found 5 watts to be the sweet spot with tubes and 25 watts with a SS amplifier. I've said this before, if a 5 watt SET 300B amplifier that can sell for thousands is not good enough for 100db speakers just what would it be good for? Horns filled auditoriums with small tube amplifiers amplifiers before there ever was SS active devices. Most with horns will never use an average of 1 watt in a home environment. The power wars went out in the 70's where the misconception of more meant better sound. Far from the truth. This is from someone that has one of the best designed 150 watt per channel A/B amplifiers along with many more powerful class D ones. A 5 watt tube amplifier will actually satisfy a large number of people with 85db speakers that listen to music as most do. 100db's of music is extremely loud for most people. That is what one watt will deliver with most all Klipsch speakers. And you will never hear any clipping. The Firstwatt 25 watt amplifiers are well suited for our speakers. Quality over quantity. 

[jjptkd]

16 hours ago, Bfoura said:

I’m looking for feedback on actually using lower watt amps on Klipsch speakers. I’m using a 300 watt Levinson 532H but eager to try a lower power tube or a First Watt solid state as soon as possible. Thanks for chiming in. 

Chorus speakers are very sensitive and can respond well to lower powered tube amps. Your room, positioning how far away you sit how loud you listen and type of music you listen to all play a big role on how well any speaker or amplifier will work for you-- your room is likely going to be the biggest factor from my experiences. 

 

Several years ago I picked up a little Jolida 102brc 20 watt tube integrated I had my Chorus II's in a roughly 13x14 bedroom and the combo was magic, I couldn't get the volume up to even half without knocking things off the walls and they sounded great and I was more than happy. Fast forward a bit and I moved to an old farm house my system was moved to a slightly bigger room and the Jolida I was so impressed with fell flat on its face, sounded dull and flat with no bass, I couldn't get rid of it fast enough.

 

Some time ago, wow must have been over 10 years ago now? I brought a complete system to my brother to his new house in Montana-- I had put it together for him it included a rebuilt pair of Chorus 1's Crites rebuilt crossovers and Ti tweeters, a Sunfire TG-III processor and a Carver A-500x 250wpc amplifier. I had it all hooked up and running at my place in WA and thought wow he is really going to love this setup!

 

I get to his house and its an "A" frame style front room with a 2-story vaulted ceiling must have been 30ft at its peak and all wood paneling like T&G pine boards on the ceiling and hard wood floors throughout. Those Choruses screeched out something horrible they were so bright and no matter how I positioned them could not seem to get any bass out of them, I could not believe how extreme the difference was from what I heard from the same system at my house at what I was hearing then. 

 

So, room acoustics / size and how close you are to the speakers and what type of music and how loud you listen are all things to consider when choosing an appropriate amplifier-- if you can tell us about these things we might be able to narrow down some choices for you but only the real way to know for sure is to try things out in your own space. Get a decent deal on some used gear, treat it well and save all the packaging materials if it turns out you don't like  it chances are you can get all or most of your money back on a resale and try something else. Good luck with your adventure, the Chorus 1's are a great speakers when done right.

 

 

[jason str]

You have a nice pro sound woofer in there and those shine as long as it's clean power.

 

2 15's can fill a small room nicely, a larger room will need help down low.

[Bfoura]

Thanks for the feedback. Sounds like I don’t need to be too concerned with the Klipsch rule of thumb for matching amp power to the speaker RMS?
 

My listening room is a converted attic that incorporates the angles of the roof design. I have a peak ceiling height of about 10’ that angles down to about 4 ft.  Speakers are set up in a 9’ triangle. My Levinson is probably overkill for these speakers but have to say everything sounds fine. I do notice when listening to the Chesky demonstration disc, the Chorus does underperform in areas such as imaging, presence and depth. But, does shine in areas such as bass, midrange purity and transparency. I would like more of the latter along with more enhanced atmosphere. I’m wondering if a tube amp or different type of SS amp design could provide more of what I’m looking for? After I install the Crites crossovers and tweeter, I’ll reposition the speakers with my speaker set up disc to see if that adds to what I’m seeking. 

[captainbeefheart]

10 hours ago, henry4841 said:

One has to consider the way SS amplifiers clip vs tube amplifiers clipping. A tube amplifier can clip and one will never know it whereas when a SS amplifier clips it will sound terrible.

 

I have found clipping characteristics to be dependent upon more topology vs what type of active device is used. A Class AB push pull amp looks just like your typical Complimentary or quasi complimentary solid state amplifier, peaks of the waveform get clamped off evenly giving odd harmonics just like any square wave would.

 

A single ended amplifier will most likely clip and or distort in a non-linear fashion giving rise to second order harmonic distortion, tubes or SS results are the same.

 

For tube amps you may encounter cathode bias power stages and depending upon bias you may encounter gross crossover distortion at clipping or even before it if biased too cold.

 

 

There is one possibility that has been discussed in hifi design books is any amp, tube or SS that has a very high amount of global feedback the amp can for a very short duration run open loop until the feedback loop has recovered. This is most likely more prominent in SS amps because they are typically not limited by the amount of feedback that can be used due to a transformer in the loop. This is a fairly complex concept and for most well designed amplifiers not a concern, regardless you shouldn't run any amp you own into clipping.

[captainbeefheart]

1 hour ago, Bfoura said:

Thanks for the feedback. Sounds like I don’t need to be too concerned with the Klipsch rule of thumb for matching amp power to the speaker RMS?
 

My listening room is a converted attic that incorporates the angles of the roof design. I have a peak ceiling height of about 10’ that angles down to about 4 ft.  Speakers are set up in a 9’ triangle. My Levinson is probably overkill for these speakers but have to say everything sounds fine. I do notice when listening to the Chesky demonstration disc, the Chorus does underperform in areas such as imaging, presence and depth. But, does shine in areas such as bass, midrange purity and transparency. I would like more of the latter along with more enhanced atmosphere. I’m wondering if a tube amp or different type of SS amp design could provide more of what I’m looking for? After I install the Crites crossovers and tweeter, I’ll reposition the speakers with my speaker set up disc to see if that adds to what I’m seeking. 

 

Although a very important variable when choosing an amplifier power shouldn't be the only concern, many times low power esoteric amplifiers, tube or SS can have a high output impedance and not drive tough loads. Klipsch speakers are easy in regard to sensitivity where you can take advantage of very high quality lower powered amplifiers, but they aren't even close to a fairly constant resistive load, their impedance can vary wildly with frequency and are reactive putting voltage and current out of phase with each other. Some amps do not like reactive loads and can become unstable giving rise to ringing and overshoot.

 

I am going to start a thread that may help people determine how much power is needed.

[henry4841]

1 hour ago, Bfoura said:

Thanks for the feedback. Sounds like I don’t need to be too concerned with the Klipsch rule of thumb for matching amp power to the speaker RMS?
 

My listening room is a converted attic that incorporates the angles of the roof design. I have a peak ceiling height of about 10’ that angles down to about 4 ft.  Speakers are set up in a 9’ triangle. My Levinson is probably overkill for these speakers but have to say everything sounds fine. I do notice when listening to the Chesky demonstration disc, the Chorus does underperform in areas such as imaging, presence and depth. But, does shine in areas such as bass, midrange purity and transparency. I would like more of the latter along with more enhanced atmosphere. I’m wondering if a tube amp or different type of SS amp design could provide more of what I’m looking for? After I install the Crites crossovers and tweeter, I’ll reposition the speakers with my speaker set up disc to see if that adds to what I’m seeking. 

Whether tube or SS quality is more important than quantity when it comes to power. Your choice in music is a big factor on what amplifier you will like best as well. If modern, hard rock or rap I would suggest SS with a few more watts then what I originally posted. Lots of choices with 100 watts or thereabouts to choose from. At this point in my life and age I prefer Jazz, blues and orchestral type music over rock of which I preferred earlier in my life. A good tube SET is wonderful sounding with this type of music. Others that prefer rock concert loud music will probably prefer a good SS A/B or class D amplifier. No set rules on this though being sound is a very subjective subject. For most that prefer SS a Firstwatt class A amplifier would be a good choice with even just 25 watts. 

[Bfoura]

There are several First Watt models available. Any thoughts on which pair best with Heritage type speakers? What about the lower watt Japanese integrated or receivers from the 79/80’s, like Accuphase, etc? 

[henry4841]

Never heard one but I have what I have read the J2 would be a good choice. Been in production longer then any Firstwatt offering for a reason. Waiting list at Renohifi.com though. 

[captainbeefheart]

26 minutes ago, Bfoura said:

There are several First Watt models available. Any thoughts on which pair best with Heritage type speakers?

 

F8, SIT3, F7, F6, J2, M2, F5, F4, Aleph J and possibly an F3.

[billybob]

14 minutes ago, captainbeefheart said:

 

F8, SIT3, F7, F6, J2, M2, F5, F4, Aleph J and possibly an F3.

Yes that's a sackful to choose.

[Curious_George]

On 2/20/2022 at 5:29 PM, captainbeefheart said:

A Class AB push pull amp looks just like your typical Complimentary or quasi complimentary solid state amplifier…

Definitely quasi-complimentary. A tube is like an NPN device. There is no PNP analog (no pun intended) in a tube. 

[captainbeefheart]

8 minutes ago, Curious_George said:

Definitely quasi-complimentary. A tube is like an NPN device. There is no PNP analog (no pun intended) in a tube. 

 

Yes sorry if I was not clear on what I was saying, tubes can only have current flow in one direction so as you say all tubes are like NPN transistors.

 

In the context of the conversation I was just saying when viewing the output of the amplifier a push pull tube amplifier will look just like a solid state complimentary or quasi-complimentary amplifier when driven to clipping.

[JohnW]

Seems I've been sucked into the Pass Labs/First Watt vortex. Currently using a Dennis Had Inspire SEP amp (which I love, but...) with my 85 La Scalas/DeanW modified AAs. 

Wondering if a SIT 3 or F8 might yield even more pleasure...