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

@richdirector  a wee dram could shave off the chill!

I love my luxman and I live in Scotland so a bit of extra heat welcome not that I feel in old Victorian lounge with ceiling 3.6m up......

I have recently acquired my first 300b and it burns hotter than my push pull el34. But, it’s colder now and don’t really notice. I’ll right back in summer!

I have both a SS class D and 300B flea watt systems but I draw the line on very hot room heating tube amps 

I’m sadly amused at people worrying over slightly inefficient amps when the world population is exploding. We are already 6 billion over sustainable. I’m using my amp without any concerns or guilt. Btw, I have no children. That’s my contribution.

To answer the OP, one of the main goals for my system was to reduce the heat in my room. I live in SoCal where temps average 85-95 degrees in the summertime, sometimes more, and electricity rates are high. I like to avoid using the air conditioner if I can.

In 2015, I had an 80 watt OTL amplifier, Class A. It was the proverbial space heater. I had a listening outfit - tank top and shorts, no socks. Not really a good look for an aging, balding audiophile. But the sound was marvelous and worth it.

The amps that replaced it are 8 watt SET mono blocks, also Class A. They barely raise the temperature in my room. It is only 70 degrees today, which is also the temperature in my listening room. I am wearing a sweater, long pants, and socks. I feel dignified. I have had my SET mono blocks for 7 years now.

When I got my SET's, I noticed that my electricity bill went down by about $75 a month. 7 years at $75 a month is $6300. My SET amps cost less than that, so I like to think that the energy savings ended up paying for them. In addition, the sound is better than ever before. Hallelujah!

I moved from Class A/B to Class D - first to Bel Canto Ref 1000 MkII and then upgraded to Mola Mola Kalugas. Little heat, small footprint and superb power and dynamics. For me no going back to backbreaking heavy amps, even if i maybe compromising a thing or two.

If someone is going to ditch their class A system because of heat, I guess a tube system is kicked out the door too! Really, the only drawback I can see in a class A is energy waste from heat dissipation.  Enough it may raise the electric bill. However in this forum that's not a problem . 

WFS probably has the EAS GaN digital amp boards and is testing them. Digital amps are the future....all DACs, preamps, and normal amps are now officially history.....he he. If you play CDs only, the best sound will be to burn the CD (with treatments done to it) onto a hard drive and play it from a streamer or computer into the digital amp. There will be integrated fully digital amps (more advanced than Technics and Lyndorf) that will have a coax input and volume control built in so you can play a CD transport directly into them.....there will be tons of these kinds of products out. It’s only just begun.....add to this that you can bi and tri and quad amp with these things and get rid of all the crossover parts.....and you can even make your own speakers as all you need is woofer/box alignment or use open baffle and equalize (digitally). We are in for a wild fun ride.......AND when you add getting off the grid using a big Giandel Inverter and using the Puritan line filter and ground filter system with dedicated ground rod just for your stereo!?!?!?!?! OH YEAH......you will never need to go to an audio show again......Nirvana will be at home.....and affordable. You can do all of this RIGHT NOW! The Peachtree GaN 1 amps are for sale......buy two for biamping....buy three for triamping.....OMG!!!!!!!

Am I repeating myself?  The GOOD NEWS is worth repeating.

@jerryg123 

WOW. Hard to imagine that people thinking they could find anything at twice the MSRP to be better, although, W4S has been beta testing a new kind of GaN amp that eliminates the dac. I haven't found anything about it, but...

Can’t go wrong with Hypex or Purifi 

Another Luxman 590AXII owner.  It's actually high bias Class A to 30 watts, then A/B to 100.  The 30 watts is enough for most everything.  That said, it's really heavy, at 65 lbs. Never gets hot to my knowledge.  It sounds like Class D is really advancing with makers like Atmasphere innovating.  When the consensus is the sound and value exceeds Class A and the products are light weight, run cool, are priced right and are better for the planet to boot, count me in.

Digital GaN amps are another step up in sonic purity from class A, class A/B and normal Class D (including GaNs). NO DAC, NO PREAMP, NO ANALOG INTERCONNECTS, NO FEEDBACK, NO HEAT.......just super sound. The only one available right now that makes sense is the Peachtree GaN 1 using the Elegant Audio Solutions 200 watt a channel board. I have no doubt you will soon see other manufacturers using this board and the 400 watt stereo and mono boards (and inside speakers too). This is the revolution that many have been waiting for.....less money, less heat, less components and better sound. Please see the GaN 1 thread here.....much much more info coming soon. Ditch those super big amps....you just don’t need them.....and ditch the DAC, and the preamp and cables....and grin!

And you can bi and tri amp in the digital domain and get rid of your transparency robbing xovers in your speakers.....now super easy to make a diy speaker that will simply blow you mind. I am making a page online that will describe the revolution in more detail. I will post a link to it. The revolution is NOW!

Ralph:

The Sharp sounds more than decent with 4/8 ohm speakers (the super cheap Sonic Impacts were always odd sounding and I even tried powering them with batteries).

This is coming from someone who has been using DH/SET 300B/2A3 amps (Audion/Bottlehead) for the past 20 years.

The Sharp's were a goof (purchased 5 of them on closeout for $75/each mainly for gifts, but ended up liking it).

I didn't even realize that the Sharp was Class D until recently upon looking it up.

 

http://www.laaudiofile.com/sdex111.html

DeKay

I have a Pass 250.8 in a 13x 23 room running Sabrina with a JLf113 V.2. It always heats the room to 70 - 72 in the winter months and to 74 in the summer- too hot despite sounding great. I run a pair of Bel Canto REF600m in the warmer months and they will probably end up being my main amps as I downsize. Inevitably the 100 pound Pass will become too heavy at some point. 

@decathlon1991 

Thanks.  I knew my uprated KRS200s are big.  But I had no idea they are planetary paragons.  Thanks for this.

What we need now is a designer that can take pure Class A down to a quarter ohm.  Guess he'll be put in jail if he can do it.

Stiff and powerful rules OK.  Just going downstairs for another wonderful dose of reality.

@jaymark you had a LSA Voyager 350 at one point, no? 

No, no, and no.

Coda Continuum #16 amp runs slightly warm but nowhere near hot. I buy my amps based on my ears. I still think the best Class D GAN Fet amp that I have listened to is probably a touch better on the top end but clearly not as hefty on the bottom end. The main benefit of class D imo is their pint size. The Coda is now my reference.

I like the sound of Class A and also Magnepan speakers. So a dilemma. My solution is low-power Pass diy amps with high-sensitivity speakers for casual listening around the house, and a Class D amp with tube front end driving the Maggies in my listening room. I don’t think I’ll ever own a Class A amp over about 25 watts. The electricity consumption does bother me. It’s wasteful. But then, I’m also a gardener with a house on more than an acre, and I use a lot of water. We all have our priorities.

Dynamiclinearity

 

you forgot about the Krell KRS200. Pure Fixed Class A down to a 1/2 ohms. One of the most powerful Pure Fixed Class A Amps on the planet. 
 

Clearthinker

i agree with you 100%
 

My response as well:

Have you done away with your Class A Amp due to Heat concerns?    NO

Will you be moving away from Class A Amp due to Heat concerns?  NO

Will you never buy a Class A Amp due to Heat concerns?  NO
 

Also Boulder makes an incredible Bias Class A amplifiers for quite some time and they don’t heat up your room. I know they are expensive and not everyone can afford it but if you constantly complaining or competing with Class A vs Class D, this should quite your noise/ maybe not. 

@tweak1 there are 4 of them on USAM right now. All priced down and dirty. 

Thanks for the feedback.

The D amps are pretty old (maybe 20 years).

@dekay Uh, Yikes! A lot has happened in the class D world since 20 years ago!! I couldn't take them seriously back then.

Clio and Ralph:

Thanks for the feedback.

The D amps are pretty old (maybe 20 years).

I may try adding an 8 ohm wire-wound to the Sharp as It's set up now @ the computer.

I haven't seen the Sonic Impact's for years - not certain if I kept them.

I'm down to one Sharp system now (2 died and I gave 2 away).

Class D is good for the spare bed/computer room as it has a large wall to wall window and no air conditioning.

 

DeKay

 

No. Never ditch Class A amps due to heat. It’s winter! Enjoy the heat. 

Am currently running a Nakamichi PA-5.

Have been wanting two BEL 1001’s since I started four-plus years ago.

(Yes, I know there’s a controversy about whether they are true Class A.)

I’ve never thought of heat as a problem, just something to be managed, though I mistrust electronics you can fry an egg on.

+1 - Keeping class A amplifiers.

I may have already commented about the Voyager GaN 350 amp. I just one FS on USAudioMart at a terrific price. He's in IN

I own and use several Class A amps - collectively around 400 pounds of them. If they didn't sound better than most other amps they'd be gone in a second. But they do, so they stay.

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.

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

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 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

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 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...

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'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!

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

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.

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!

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.

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

 

 

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!

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 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. 

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

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).

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”??

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.

@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.