Ditching Class A Amps due to Heat - Sort of a Poll

Someone mentioned space heater, as much as I loved my Threshold amp, that's exactly what it felt like. Very happy with a Mcintosh now, crazy low energy usage and sounds almost as good as a class A or tube amp. Running 24/7 so that's important to me. If I only listened a few hours a day I'd probably choose differently though....low power SET for my Omega 95db bookshelfs.   

I have been using tube gear for several years now and will never give them up. However, I recently borrowed a FirstWatt F6 from a friend. After I listened to it for a few hours I made an offer and now it is mine. I just ordered a pair of Tekton Double Image speakers to pair with it. The purity and accuracy of its sound won me over. Now I have an outstanding set of tube gear and what I perceive to be an equally amazing Class A amp. I will keep it, heat and inefficiency be damned. 

No heat concerns here. My pair of 1980s Crown PS/200 amps benefit from a really good chassis design that keeps them very cool without a need for any fans. Actually cold when playing music not even close to being hot at idle.

I don't have air conditioning.  I had to abandon (at least in the summer time) my 400W class a amp for a 180W class A amp.  (I'm talking watts of heat, nothing to di with watts per channel which is close to single digits).

Jerry

@retrocrownfan Your ps200 amps are not Class A, they run squarely in class AB or B.

Pass XA25 owner.  I am inconsistent concerning leaving it on or off.  Last month my energy bill was for 300KWh.  The amp gets to 120F at most.  I like it, I won't get rid of it.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

I love the sound of a big ass, power sucking, space heater, street light dimming Class A amps…Glorious! 

I purposely avoided Class A because of the heat and chose high bias Class A / AB amp as a compromise. I enjoy the sound and anticipate a longer service cycle out of them (electrical charge was not the concern). I was also aware of class D technology is on the rise but did not have a full confidence as I had with the high bias class A/AB amp.

Living in the area where the temperasture is around 95 F for at least 3 month of the year. Have p.single ended tube A class amp and preamp and do not switch on the amps at all during the summer. Than again, hi fi is a winter sport, plenty of other interesting stuff to do during the summer...would I change for some other kind of amp? If I find some that gives the same illusion of live music (like tubes do) yes, but so far ss or hybrid did not delivered it. Have not heard any ganfet amps, curious about it...

You'll have to pry my Pass XA 30.5 out of my cold dead hands. I live in New England and this time of year I'm grateful for the heating bonus to go along with the spectacular sound.

I own & really enjoy the best/ worst of both worlds. Full class A, 100 watts / side tube integrated amp. Rogers High Fidelity EFH 200 Mark II. Sounds great; very powerful, dynamic, detailed w/ full frequency extensions but as airy, beautifully toned as I could ever want. It should at its price & does & should do so for a long time. 
 

That said, it puts out some serious heat all the time. Living in New England, I don’t mind 8 or 9 months of the year. For myself, very much worth the trade offs.

I have a Pass Labs class A amp and yes it does get warm but never felt any heat issues from the amp. I live in the northwest where summers can get hot here and we don’t have AC. Still not a problem. I went from a class A/B tube amp to this amp and am very pleased with the upgrade.

So even an audio forum can’t get away from political comments. 

It’s considered a feature in northern Minnesota.

They’re in my some of my active speakers - and they’re excellent, especially in winter.

Living in Florida it's a double hit to the electricity bill. First the cost of running it, then the cost of running the AC to cool the room. I'll keep my Benchmark AHB2.

I enjoy warm and full sound out of class A solid or SET tube amp.

 

Thus I am happy to live in Pacific Northwest Washington State.

 

It is not that hot during summer.

 

It is good to have extra heater during winter.😀

 

Also the cost of electricity is the most affordable in WA.

 

Thus I may live in Washington State for my life.

 

Thomas

I have to say that over the period I have running my Class A mono amps, coupled with my tubed preamp, I have been loving my music again. There is a sweet spot with these mono Class A amps that allows listening with no fatigue, glare or otherwise unwelcome issues or noise. I would characterize them as "warm" sounding so it depends on what you prefer.  My units have a stanby mode so the "Heat" is only an issue when in use, but they do run Hot! I have also installed some micro fans which are very silent to move air from behind the units which helps.

Overall the most musical combination I have owned and enjoyed!

I have no intention of getting rid of the two class A stereo amps I use in my triamplified DIY fully horn loaded system because of the anthropogenic global warming scam.

I have a class A amp on my main system and a EL34 tube integrated on a second.  The heat is a non-issue for me. I've owned some good quality class D amps (2 different Bel Cantos and a VTV Hypex along with some more basic units) and like the sound quality of my current amps better. The only advantage I find for class D is that they can be left on all the time, but I really don't expend that much energy in pushing the on/off switch. 

@kingharold +1

Mike

@kingharold funny. 

 

So far it's about 5 to 1 that people are not ditching Class A, good to hear. Hopefully we will never see an Energy Star Sticker on the back of Amps :)

A big defender of Class D claims that Class A is going away on it’s own and would never become effected by limits placed on electrical consumption or heat output, but just because everyone no longer wants it or wants Class D or similar.

I’ve been running class A tube amps for over 50 years. I’ve been manufacturing them for nearly that long as well. I’ve never liked the heat, so it was really nice to find that after 5 years of R&D that we had a class D product that sounds better than our tube amps. I run them at home now and don’t miss the tubes at all.

(FWIW Our OTLs have gotten very nice reviews and awards in the high end press, best sound at show, stuff like that.)

What makes an amp sound a certain way is its distortion signature, unless its output impedance is high enough that you run into frequency response colorations as well. Class D amps can have a very low output impedance, eliminating the latter issue and it is possible to have them have similar distortion as tube amps make, meaning they can be smooth through the mids and highs, which is also why people like class A amplifiers in general.

Its very likely that I’m the person @brianh61 is referring to with the comment above.

I went from class A to class D on account of the sound, nothing else. Class A is doomed at this point; ten years from now class A offerings will be vastly reduced and it will be by market forces and not some ’green’ agenda (which isn’t a thing when it comes to amplifier classes of operation- no one is out to regulate that).

@atmasphere

Thanks for chiming in. With your selection, it is still more than 5 to 1 in favor of Class A over anything else in this thread.

Have you done away with your Class A Amp due to Heat concerns?    No. Because mine don't generate heat.

Will you be moving away from Class A Amp due to Heat concerns?  No. See above.

Will you never buy a Class A Amp due to Heat concerns?  No. Mostly because I'm not going to buy another amp.

Let me state at the outset that I own SS amps. Monoblocs. Actually, SS exclusively along the entire signal path.

A few extraneous thought arose as I read through the thread. I keep my house at 63 - 64 degrees in winter. The room where my amps are is slightly colder because it's over the garage and the thermostat is down the hall.

The majority of responses focused on tube Class A. I'm not going to defend SS Class A or denigrate tube Class A.  You listen to what you like and what pleases you. Many years ago, before I bought my system, I read a lot of arguments about tube versus solid state. In that reading I found a gem of a statement by one of the better well-known designers. I think it was Carver, but I could be way off with that. The statement was, essentially, that solid state amps could be biased to sound like anything... tube included. The bottom line is decide what you like to listen to, then buy the best you can afford. I found what I liked and bought that. I guess they were biased correctly for me.

If you really want to get into the climate change concerns, answer these questions for yourself. What car do you drive? The amp you're running is minuscule compared to a car. For myself, I got rid of my ICE vehicle and will drive 100% EV as soon as it arrives.

Whatever you drive; how many times do you walk instead of drive? I walk a lot (and did so before I got rid of the ICE.) Maybe I'm lucky in that I live in a neighborhood where walking is feasible. It only takes me 30 minutes to walk to the supermarket or hardware store, etc.

What temperature do you keep your house at? As stated, I keep it 63 - 64 in winter. 73 - 74 in summer.  I live in the northeast.  It gets both cold and hot and humid.

To brian61. You really should have differentiated your question between SS and tube amps.

Happy listening.

No AC in the house. Only very quiet ceiling fans and windows that open to the trade winds. So despite my tube gear I really don't expend much electricity overall. As for disturbing neighbors, I don't play my stereo very loud, in any case.

I admit I’m more of a green, tree-hugger type, but I’m into audio for great sound and if it took a fire-breathing, Class-A monster to get the sound I love I wouldn’t think twice and would never say a word to anyone else who chose to go that route. That said, I really wish more solid-state, Class-A amp manufacturers would do like Plinius and some Clayton models do and employ a high/low bias switch so it’s possible to leave the amp on 24/7 and not ravage the electric bill or turn the room into a sauna. Seems like such a simple thing to implement, and it comes with the added benefit of not having to constantly turn the amp on and off, which greatly compromises long-term reliability along with the annoyance of having to wait for the amp to reach its optimal operating temperature. Case in point, I recently got my DNA 0.5 amp upgraded by SMcAudio where the on/off switch only operates the power light to let the wife know it’s on when in actuality the amp is always on when it’s plugged in. They do this because they feel strongly that leaving the amp on in a steady state is much better for amp longevity than turning the amp on and off and putting it through the stress of temperature changes, etc. Anyway, I say to each his own, live and let live and so on, but if I did have a power-hungry amp I’d be taking a long, hard look at the new GaN amps from the likes of AtmaSphere, AGD, etc. as we really seem to have turned a ground-breaking corner in both sound-quality potential and efficiency. When Ralph says he’s happy using his new GaN amp over his wonderful OTL tube amps that speaks volumes to me. Anyway…

I have owned tube amps and Class A amps (Plinius, Bedini, Pass Labs, First Watt) but my favorite is my Jeff Rowland Continuum S2 Class D integrated.

@zufan 

You wrote, 

Somehow Biden is involved in Class A discussions.

Indeed. Sort of Tourette's syndrome -- how he lives rent free in the coconut shells of creatures unable to control their distemper.

Have you done away with your Class A Amp due to Heat concerns?

Will you be moving away from Class A Amp due to Heat concerns?

Will you never buy a Class A Amp due to Heat concerns?

Thanks for chiming in. With your selection, it is still more than 5 to 1 in favor of Class A over anything else in this thread.

@brianh61 Just to be clear, my response to the above questions are all 'no'. Your response to my post (also above) suggests to me you thought otherwise.

I replaced my class A triode OTL amps because I have a set of amps that sound better.

If a lot of people prefer the “class a” sound but would be happy not to have the heat or electric bill, maybe there is a market for a class d amp voiced with 2nd and 3rd harmonics to sound like “class a”??

The KRELL XD lineup does not get hot, about the same heat as the Benchmark AHB2. The KRELL is Class A using an iBias method to keep temps low. The AHB2 sounds like a Class A amp too (better to some ears).

we have tested many class d amplifiers in our store hypex ncore and

gain and a few others none sounded as good as class a/b amplifiers

 

the first class d amplifier that really was exceptional and truly musical is the Avik amps they are built with novel noise reduction technology and their u180 integratedis shockingly good as both an amplifier and dac the amp is musical and engaging

 

so far the t+amplifiersclass a/b are still our favoritesthe avik in our second show room is becomming anew favorite for a more affordable integratedamp/dac combo

I own a pair of Pass XA60.8s which have an idle power dissipation of 400W each. I don't think I'd consider buying an amp that use more power than this at idle. 

My Pass amps have not been in my system for more than nine months since I've been using a pair of 300B PSET amps. These have plenty of power for my system and I like the sound a bit better (although the XA60.8s are very nice). My 300B amps are also class A, but have an idle power dissipation about half of the Pass amps. 

I do have a Purifi class D amp that I use in my bedroom system and it's nice to have extremely low idle power dissipation so that I can just leave the amp on all the time. But, as good as it is, it lags behind my Pass and 300B amps. 

Class A for me.  Two First Watt amps,and a pair of Monarchy Audio mono blocks.  Listening to well reproduced music brings me joy. I like what I like. Oh ya, they run hot. I still love them.  

I have two Class A amps (modded Plinius SA103 and Reference Line Silver Sig) and love ‘em both. But I’m open to this new GaN-FET stuff. A friend is bringing over a Peachtree and the Atma monos in 10 days for a head-to-head against my amps. Should be interesting!

Has anyone successfully used class D amps with 16 ohm rated speakers?

I've tried a few versions of the cheap Sonic Impact amps as well as the Sharp SD-EX111 mini system with such and the sound of the mid's on up is odd/wrong.

Both were fine with 8 ohm rated wide band single drivers I use, as well as with a conventional  2-way 8 ohm speaker.

I balked at purchasing a recently discounted/cheap Class D integrated amp with "room correction" capabilitys because of this, but also because of the software/hardware required to use the "RC".

Anyone else use Class D to run 16 ohm speakers?

 

DeKay

 

 

Luxman 590AXII.  Replaced a tube preamp/cllass AB amp setup. Dissipates 400w continuous, which is welcome this time of the year, as I get up about 4 hours before my wife, and the house heater doesn't go on until she's up.  Room is nice and cozy.  Summers are mitigated by an efficient ceiling fan.

I own the Ayon Spirit V PA, which is a Class A amplifier and it does NOT run hot.  My Rogue Stereo Super Magnum 90 which is Class A/B ran WAY hotter that the Ayon.  I think the Ayon is one amazing sounding amplifier!

For 2-ch system, I use NcoreMP, 6 channels (LXmini + subs) use 0.8 A (120VAC = 96W) including power to N130 - everything runs cold.

For HT system, the Denon X6400H (class A/B) runs so hot, I added a cooling fan, which is very noisy when it turns on, and is distracting while watching movies.

Having that experience, I avoid gear that needs cooling and/or is very inefficient for myself. I also wouldn't let heat prevent me from chosing gear that is worth the compromise - if I thought it was worth it.

@dekay I use an Atma-Sphere Class D amplifier to drive Quad ESL 57s (15-ohm nominal) with no issues.

I've owned a Krell 100wpc space heater for 30 years, I kinda like the natural warmth in winter. Seriously, I've got a big room and, even then, it can get too warm in summer, so I have to open the door that sits between the speakers. Found out quickly that I preferred the sound with the door open. No more problem with the heat and I have never found a different transistor amp that does acoustic instruments as well as the Krell. Keeping it!

My issues with ss Class A have more to do with weight than heat. But these are niche products, in any event - I don’t think any Class A maker aspires to take over the market - they seem motivated to create products they love and make a living at it, and for that they have my thanks. That being said, when I bought a second amp, it was a tube, so I guess at heart liking the sound still guides me more than practical considerations

I live in the desert.  Burning up in the summer and cold as a witches tit in the winter.

My class A and tube amps collect dust in the summer.  Even my class A/B Quad 909 runs too hot to run for the summer here.

So Class D in the summer, Class A and Tube OTL in the winter...

I ran class A amp for a number of years, great in winter, terrible in summer. In summer central air kicked in increasing ambient noise floor to a distracting level, 845SET I presently own has same issues. More recently thought I'd give much lower power class A another try, same issues, went to 300B SET, glorious SET sound quality without the heat.

I am thrilled to death for the choices of class A ab -D- tube -H . What ever choices we have. The more the better. As a individual our ears will let you know how good the sound is coming out of what ever equipment it might be. Life is about having choices that suits the individual needs. I own about every class of amps there is to offer. As I get older the weight of these amps are kicking my ass but I will always use and have them because of the sound it produces. Thank God for choices

My coda amp has almost 20 -1st watts in pure class A 

then 150,300,600 wpc and sounds great never gets real hot ,40 bipolor 

transistors on the outputs Very high current over 120 amps short term 

will handle any Loudspeaker loud, there  are 2 other power options with more power but less watts into  pure class A .

I love my Luxman 595ASE space heater. Sounds great and keep the space warm. I’m in the Northeast and I’m always cold. :)

Anyone else use Class D to run 16 ohm speakers?

@dekay Yes. I run them on my Classic Audio Loudspeakers. They work fine on there- no complaints.