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I see MC is up and Atom.. That's planet "Uranus", runs VERY cool, but a slight, "outhouse" smell as the day goes on..:-)
I don't know what your winters are like, but I swap my tube amps out in the summer for class Ds. I use Valve amps in the late fall, winter and spring (cool summer nights if we have any). It keeps the house quit toasty, when I really get going.. I use a Mac preamps, C20-C2500s, all valves.
Have the best of both worlds.. No idea on your speakers, and the actual room size.
Mac has a hybrid. Valve pre section, and SS amp section. They run pretty cool. They will provide you with running temps too. They always have good data, just have to know where to find it..
Personally a valve pre amp with Valve/SS power amps, nothing better.
Next in line for the money, a GOOD integrated, tube pre/SS amp section.
I wonder if anyone is making an Integrated with a tube (valve) pre amp and Class Ds for the power amp? I'm sure they are out there. Easy enough to do it with separates.
The valve in the preamp can get hot to, 6SN7s get hot, a lot of preamps use them now too..Carys, and Freya +, I love them, but they run HOT...
Why not just vent the heat out of the room? A ceiling vent isn't expensive to install and some dryer duct hose will send it out of the house with the help of an inexpensive low speed fan. Then air conditioning won't have any trouble keeping up; you may not even need it.
But here's the thing. Most tube amps get docked about heat due to the filaments of the tubes. Literally the only tube where this is a thing is the 6C33; with any octal-based power tubes the heat contributed by the filament is inconsequential. So that means most of the heat is coming from the class of operation, and will be about the same amount as a solid state amp running the same class of operation and making the same power. I know this because our amps make about as much heat as any for their power, but if in Standby (no B+ on the power tubes) you can have the amps on all day and walk up to them and grab a power tube and hang on. They just aren't that hot.
The only way I can think of to get away from that is a class D amplifier. So if that's out of the question, then do vents in the ceiling. It will cost a few hundred dollars but you can have the fan operated by a wall switch and no impact from the heat of the amps in your room as long as the vents are above the amps (heat rises, after all...).
@atmasphere Actually my AC works well enough to cool the room, BUT the issue is that it is a little noisy, just as any fan vent would be.
Like you stated, my tube amps also run coolish when they are in standby, but once the voltage is applied, up goes the heat expansion. My amps only use two KT150’s per side, so in the big picture, they do NOT give off a huge amount of heat, but they give off enough to really make my very small room nice and toasty within about an hour. My ss amp does the same thing, after about an hour and a half; but here’s the thing, it would be great if a tube amp existed that gave off no real heat after multiple hours...maybe this isn’t realistic, given the technology, but is this possible??
bottom line, any tube power amp with any meaningful power output will have output tubes that will provide a decent amount of heat
flea watt amps still produce heat - 2x 300b’s or 211’s or 845’s or el84s - of course then it is just a matter of degree, one person’s ’minimal and acceptable’ is another’s ’too much’...
hybrid amps might be the answer... really only low level signal tubes produce what most folks would consider insignificant amounts of heat
Check out this amp. It has tubes to give you that tube sound, but they’re not the output tubes. Much less heat!
they have a 300 watt amp also.
All the best
Benchmark AHB2 class A/B power amp (2x200W@4ohm) runs very cool (SMPS, modulated power supply rails). It was designed to sound neutral/accurate, so perhaps you can use tube pre, if you like warm sound.
Musical Fidelity has amplifiers with Nu-Vista tubes. From what I understand they were being developed as a new tube technology but was shelved due to the invention of the transistor.
I mention these because they look nothing like a traditional tube so do they produce the same heat or any?
Does anyone have knowledge of these tubes they could share?
We had a client actually return a wonderful vintage tube amp because he thought it gave off too much heat. He was already aware that tube amps give off heat, but it was apparently more than he expected. Worth noting that this was just a little 7189 stereo integrated. The client was worried he would touch a hot tube accidentally, even though they are at the rear of the unit.
If you are concerned about heat. A tube amp is not the right choice.
@austinstereo. That is interesting. I am not concerned about the issue of injury, as I never let folk get near the tubes. Your client has a point though if he had little children or pets that could get injured!
The issue I brought up in my OP, has to do with the fact that the room size is also crucial. The smaller the room, the bigger the problem.
Some folks probably don't comprehend why this would be a problem, as they enjoy a large enough listening room that a warm/hot amp ( heat wise) won't ever be an issue.
You could consider a class D amp with a tube input buffer. The Purifi modules add very little of their own sound signature, but require a front-end driver board to provide some gain and impedance matching. There are a couple of companies that make amps using these modules (which are very efficient) that use a triode-based front end.
ATM makes an Korg NuTube based input buffer. I assume they make a complete amp that uses this buffer, but I don't know the model. The ATM buffer seems a bit pricey for what it is, but it might sound good.
I haven't heard either of these, but have heard an amp using the Purifi module and it is very clean and detailed.
@daveyf The amount of heat generated by a particular amplifier is predictable to a close approximation based on its current draw. All of the current drawn by an amplifier is either converted to sound, which is subsequently converted to heat, or else it is lost immediately to radiant heat. This is a consequence of the 1st and 2nd laws of thermodynamics. There is a small amount of energy (either as sound or as heat) that escapes the room, so the amount of heat retained in a room is somewhat less than the amount of current the amplifier draws.
This holds regardless of whether you are talking about tube or solid state. It is just the laws of physics. Any energy introduced into the room that is not lost through the walls will be retained in that room and sooner or later be converted to heat.
If you want to solve the problem without relying on AC to remove heat, the best bet (especially if you want class A amps) is to build a system around high efficiency speakers. These usually can be driven by amplifiers that draw relatively little current even though they are class A. The other alternative is to use a Class AB amp, which will draw less current when the music doesn't require it.
As for me, I just put in a really nice quiet two stage AC system in my listening room, which had formerly been so hot I couldn't use my favorite amps during the summer months. My new AC cost 6K, which was a pittance compared to my investment in audio. It is a high efficiency system that will pay for itself easily over its lifetime.
Yes, the Purifi module is class D and I agree that class D amps can sound too sterile. I had an NCore based class-D amp previously and that is how I would describe it.
However, the sound signature of amps based on the newer modules (particularly the Purifi) are going to depend more on the input driver design than the class D module. The Purifi module has vanishingly low noise and distortion, but limited gain (as well as low input impedance), so a front-end driver is required in most situations.
I believe (although I haven't personally heard) that the right input driver can create a sonic signature that is pretty similar to whatever you're looking for. I could be wrong, but I'm giving this a try myself by building a set of DIY monoblocks using the Purifi module so that I can experiment with different buffer/drivers. I'm planning to build (or buy) a few different options to see what works best in my system, including building a triode-based buffer.
The VTV amp I linked to above uses a triode buffer that looks interesting, but I think I'm going to design and build my own.
I think VTV has a pretty liberal return policy, so if it seemed like it might work for you, you could give it a try.