Seeking hot running amps

Which poweramps run hot? I am looking for a hot running amp to warm my room in the winter. I have heard of Krell, pass, threshold.
Add Plinius to the list.
Surprised you`re not going with tubes. It`ll give warmth & the glow of embers.
My Krell Ksa-250 runs pretty warm...or, a pair of these in mono-block configuration (MDA-500) should be a great winter space heater.

Don't forget about big tube amps...lots of heat.

Pass X-350 gets pretty hot
About 25 years ago at work we had a Lab/Test Berth which had a big old computer in it. The air conditioning was badly set up and when the lab was unoccupied overnight and weekends is got uncomfortably cold when the lab technician came to work in the morning. So he began to leave the computer turned on all the time functioning as a room heater, which was contrary to our operating procedures.

We soon discovered that this particular computer was far more reliable than similar ones used elsewhere. That's how we learned that continuous operation is more reliable than ON/OFF operation (at least for this type of computer).
Atma-Spheres! Check out (remember the atma is spelled with a's and there is a hyphen, too)
The hottest amp I've had was a Pass Aleph 5. You could not keep your hand on it very long type of hot.
why don't you just get a space heater, it would be alot less expensive.
My Lamm M 1.2 reference are just warm enough to roast a mashmellow on during a frosty morning. I would look at these. I may be exagerating the heat a little but you get the idea.
The Gryphon A class amps such as Antileon signature will definitly heat the room and sound better than most amplifiers,down side is the weighr the stereo version weighs about 220lbs.
The hottest running amps that I have had are

Conrad Johnson
Mark Levinson 33H & 33
tubes are welcome. my audio research sp16 (6 tubes) emits a little heat. I want to heat and warm the room at the same time.
A Pair of Mark Levinson #33's should fit the bill quite nicely! Lots, and lots of cooling fins-heatsinks on these puppies, plus they're just about the size of large radiators, so when your freinds come over, they will comment "Hey your Radiators even play music too!? Woah, taht;s cool!!" lol Mark
Cary V12i definitely heated my room up.
Parasound amps are known to run very hot. I read that of the older models a few years ago, so maybe they've cooled them a bit since then.
Still, no matter which amplifier, even tubes, you get, the most heat that you will get from the excess heat given off, it won't be more than the rated power of the amplifier, or about 400 watts for a high powered tube amp. Just get a space heater or turn on 4 100 watt bulbs!
Bob P.
plinius they run at 165 degrees they are biased at pure class a. plus they sound incredible
Ah yes, heat. Class A operation is the reason for heat. Fact is, if you want it to sound right, it has to be class A.

I've never understood why a person would spend thousands or 10s of thousands on a stereo and then compromise the whole thing (and the investment) because they were worried about heat.

A customer of ours in Guatemala runs one of our big amps and has no air conditioning. Instead, he has ductwork positioned in the corners of the room where the amps are, and has a fan at the other end of the ductwork, drawing the air out of the house. His room stays comfortable year round even if the amps are on all day (I know I was there), yet the room is quiet. Elegant solution.
Well, there is more than just "HEAT" when there is heat, there are tradeoffs, for every degree something runs hot, there is a reduction in reliability, as well, the heat comes from somewhere, it's energy, wasted energy, you wouldn't run your car full throttle all the time an use the brake to go 30 miles an hour, there are intelligent ways to use energy
Joule Electra OTL tube-based amps. I have a pair of their 100 watt versions in my dedicated Canadian basement listening room. I close off the heating ducts to the room and turn on the amps an hour before I listen. Works great for me - I STILL have to have a blanket on when I listen to music in the winter.
My vote goes to the Mccormack DNA-1. The fact that it operated so hot, actually contributed to my getting rid of it. An excellent sounding amp.

Allanbhaganinfo, your analogy does not work. Class A amplifiers generate heat because they are on all the time. The engine in your car makes heat- all the time- because it is on all the time too. But it is not correct to compare the two!

Class A amplifiers get used not because they make heat but because they are the best sounding amplifiers made. IOW, any amp that is not class A won't sound as one that is (all other things being equal). Especially when one is investing thousands of dollars in an amplifier, one ought to be aware that the sound quality investment is better served by an amp that is class A (and runs hot).

It is assumed that the amplifier is also designed to handle the heat that it makes- we've been making class A amplifiers for the last 28 years and so far the heat of the tubes has not caused us any reliablity issues- and we get good tube life too. Its all in the how you handle Class A requirements.
I'd like to hear someone tell us how Atma Sphere amplifiers are anything BUT reliable. Personally, I haven't come across a more reliable amplifier, be it Class A, Class A+, Class A/B, Class B, Class D, or Class XYZ.

Yes, if you want heat, a Class A amplifier is your ticket. Nice in the winter. The power draw isn't a positive, but that's about it when it comes to drawbacks. I concur that Class A often goes hand in hand with great sound. The Atmas being as good a Class A amplifier as you'll ever come across, particularly if tubes are your cup of tea.

Never understood those who were running their Atmas in Class A/B mode. As I like to say, "In for a penny, in for a pound." In my opinion, you run your Atmas the way they are supposed to be run, with the kind of speaker they are supposed to be mated with, or you find some other amplifier.
Hi Ralph, yes, class A does have its sonic attributes, I never said it did not, but the heat is an issue, what you say go against studies done by the US military and us, showing that tube life is directly affected by heat, the higher the shorter the life, as well it goes against what has happen to so many Class A amp manufacturers in the past, going out of business due to reliability issues.
Class A tubes also deteriorate at a faster rate than ones in Class A/B amps, again due to the heat (or always being on).

A well designed Class A/B is harder to implement, "True" auto biasing and power supplies need much more attention , when this is achieved a Class A/B amp can be excellent but I agree, not too many get it right.

As for the analogy with the car, IMHO it's correct, Class A tube is on all the time, it requires the power, to be on all the time, from the supply, a well designed AB can be a factor of many times more efficient and many times cooler.

I'm not saying that Class A does not have it's place, but to say that Class A should be worth more than AB is wrong and misleading, AB can be more expensive and complicated to implement correctly and for people who don't want to risk their family and friend/Pets to burns or heat discomfort, as well for those with an eco conscience, Class AB can be as excellent if well designed.

Good tube life is relative, we have amps out there with the original tubes that are way over 20 years old.

I mean, don't take me wrong here, we will be making Class A amps again in the future, we just don't feel that it's worth more only because it's Class A.

Last of all, No one is saying that Atmaspheres are not reliable, my comment was general for Class A vs. Class AB and what heat does, and that is with us having 36 years of research in the matter.

Get near my Sugden and it feels like the heat from an engine block.
Great for warming up a small apartment.
Notwithstanding the perceived heat given off by the previously mentioned amps, no amp gives off more heat than its rating, which in the case of tube amps is about 300 watts, 500 watts tops. The smallest electrical space heater gives off more than that. It is silly to buy an amp for its "appartment heating" capacity.
Bob P.
This is not just for warming my room, also listening to music.
Plinius makes great sounding amps that, when run in class A, will heat up the most chilly of rooms.
Which amps run cool? I am looking for an alternative to my freon A/C unit that sounds better than the noise IT makes. What a STUPID post.
We have a customer in Guatemala who has our biggest amps. He has no air conditioning, and does not need it (Minnesota is hotter in the summer than Guatemala...). This despite the amps often being on all day long; the room stays very comfortable. He does this by having vents in the ceiling above the amps. The hot air is then moved out of the house. It works very well indeed (I was there)!

Its probably not a good idea to choose an amp based on heat (or lack of heat) output. But it is a fact that if you choose an amp for its low heat output, it will represent a compromise in the sound of the system overall. So far no-one has been able to change the laws of physics...
Wouldn't -amp- / -speaker- matching for the best sound be paramount ?
Mark Levinson 33 run's really HOT.
A funny thing happened the other day. My amps were left on by my kids in my Music room with the door closed for 3 days. Did I freak........? The door is weather stripped and the room is relatively airtight.
The ambient room temp was 94 F . The room is set for 68 F. How is that for hot.
I am sure that my electrical meter was spinning out of control. Luckely our power is all hydro electric.
I'd vote Pass and Parasound JC-1's.... both those puppies can easily heat a room.
The ARC Reference 600's produce so much heat that, short of running them in a gymnasium, they're too hot to be practical. They need a dedicated room (and by this, I mean a dedicated amplifier room).
Krell KSA 100 the first or second one made runs realy hot my brother has on this thing idles at about 400 watts but that's when you know it's pure class a.
Oh here is a funny thing about my Lamms, my wife has decided that they are perfect to put sticks of butter on a plate and use them to soften them since they are so warm. I told her to make sure she uses a large plate since each amp costs about the same as a good used car.
Why not throw a hot preamp on top? My old Krell KCT preamp ran much hotter than my Krell FPB-400cx amp.
If you can find a working example of the old Rappaport amp it runs as hot as any amp I've encountered. I remember it as sounding warm and lush.
Bryanhod, I love that!
Hello Bryan, I've got a Rappaport Amp 1 in perfect working order. I rebuilt the outputs with hand-matched motorola OEM transistors and rebiased the unit about 5 years ago and it has about 30-40 hours on it. Just finding the proper output transistors was a complicated matter. Cosmetically it's in pretty good shape for its age and i would consider selling it for the right price considering its rarity.
Joe B.
2nd the Parasound JC1s; however, they have a low-bias / high-bias setting which allows you to control the class A amperage (and heat).

high bias turns my room into a sauna (small room), but damn they sound good
O.k., this is an admittedly silly thread. That being said, it would seem as though getting hot running amps to also use as heat is serving two needs- audio and heat source.

Since we as adiophiles need both (if we're in cooler climates) it behooves us to use class-A amps. Better sound, throws off heat.

My listening room is in the lowest part of the house and is notably cooler than the rest of the house in both the summer and the winter. Hot amps work just fine for me!

Using a space heater would therefore be less efficient
because in addition to the heater, you need to run your amplifier(s)!

Any class-A OTL will heat just fine...
Clayton Audio. Pure class A
If you want great sounding amps and not just space heaters, try BAT VK150SE monoblocks, especially if used with a BAT preamp.
Optarchie is correct.

I sencond his Clayton Audio Pure Class A mono block..I have them and they warm up very nice.
OTLs - get some Atma-sphere monoblocks with a gazillion tubes.
Pass Labs, Pah, runs a bit warm, but I could keep a hand on Aleph 3 for 10, 20 seconds. Now my Viva Solista 22watt SET is really warm. You can cook a meal and run the central heating with that, as well as being a great sounding amp. What I don't understand is that it is Italian, it is pretty hot there in the Summer, how can they stand it? I have to have a Karan K180 for use from may to September in the UK
Jtwrace is a Clayton dealer and should disclose same when mentioning his product.

For any reason.