Hi everyone!
I’m looking for some guidance on choosing a Class D amplifier for my setup. Here’s a bit about it:
I’m looking for some guidance on choosing a Class D amplifier for my setup. Here’s a bit about it:
- Speakers: high-efficiency Goodmans Axiom 201 - 100 dB sensitivity and 15-ohm impedance. Loud with just a few watts!
- Current Amplification: forum Pass ACA monoblocks, which sound fantastic but run quite hot - an issue, especially in summer.
- Preamp: Khozmo passive preamp, which is both single-ended and balanced, with a 10-ohm output impedance. I also have a Korg Nutube sometimes used for its harmonics.
- Source: Denafrips Ares II DAC.
Goals
- Energy Efficiency: I’m looking for an amp that runs much cooler and uses less power at idle than the Pass ACA.
- Compatibility: I don’t need a lot of power. Even a few watts go a long way. More concerned about having a clean, noise-free signal since any noise can be easily heard.
- Sound Quality: I’d love something that retains a natural, musical sound. I’m open to a bit of experimentation to find the right match. Midrange is essential, bass is important. Extension? I'm getting old.
Questions:
- Has anyone here used Class D amps with high-efficiency speakers like mine? I’m curious about your experiences with noise levels and overall sound.
- Any recommendations for specific modules or even ready-made amps that you’ve had success with?
- Any tips on integrating the Korg Nutube preamp into this chain? I want to ensure I get the best of both worlds without introducing noise.
- The fact that I am interested in the Fosi V3 monoblocks gives you a fair gauge for how much I want to spend.
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I forgot to tell you that I strongly considered stepping up from the ACAs into the Nelson Pass construction ladder. (F, J, or others).
In fact I like this class A sound so much that I'm even considering having a separate amplification for the winter months when I don't care about the heat output by the units.
I just honestly can't live anymore with the irony of having AC turned on while heating the same room with my monoblocks.
In fact I like this class A sound so much that I'm even considering having a separate amplification for the winter months when I don't care about the heat output by the units.
I just honestly can't live anymore with the irony of having AC turned on while heating the same room with my monoblocks.
How much heat does a ACA monoblock produce, maybe 25 watts? You realize your body is producing 4x that. 😉
jeff
The TPA3255 is a good option.
Aiyima (A07) and Fosi (BT20A PRO) has good integrated units.
I have 2 Fosi units for testing. I listened to Aiyima in a recording studio, which asked me a suggestion for an additional amplifier for monitor.
I liked both and the studio owner is satisfied - they performed A/B blind test with the Alesis RA150 (class AB) and didn't find difference.
I tested & worked with 3e Audio 5se amp class D amps on a horn + 12" woofer. Horn CD is 109 dB sensitive & had to be toned down 10 dB with L-pad.
The 3e Audio 5se is just about the quietest amp I've ever used. It also sounds very good -- no signature other than extreme clarity, detail, dynamics, just doing what the music asks.
It's a bit quieter than the Hypex nCore amps, which I have in an 8-channel Buckeye config. That is also a very quiet amp.
In normal use, it barely gets warm. Obviously very efficient, this wee box. Helps that the power supply is external, much like for a laptop.
The 3e Audio 5se is just about the quietest amp I've ever used. It also sounds very good -- no signature other than extreme clarity, detail, dynamics, just doing what the music asks.
It's a bit quieter than the Hypex nCore amps, which I have in an 8-channel Buckeye config. That is also a very quiet amp.
In normal use, it barely gets warm. Obviously very efficient, this wee box. Helps that the power supply is external, much like for a laptop.
I use the Tekton Perfect SET 15 with upgraded crossovers. They are rated at 98db @ 2.83V with an 8 ohm impedance. I have used an Elekit TU-8200DX, about 4 watts single ended (very good), then a DIY DCG-3 pre-amp with a DIY Aleph J (didn't care for that combo), then the DCG-3 with Nilai DIY500 Class D (absolutely quiet, grabs the speakers by the b@!!s, really enjoyed this combo). Latest combo is the DCG-3 with a DIY F-4. This combo is end game for me, detail and sound stage like I have never heard before, and silky smooth; though I still keep the Nilai Class D around for when I want some real slam. I have tried a few other DIY preamps as well but always come back to the DCG-3. The usual disclaimer though, my ears, my room, my preferences.
I used my channel Island/ Hypex original UDC modules with my 96 dB speakers, dead silent but my Audio Note Neiro 2A3 amp was also dead silent and sounded much better, Hypex has come a long way , I would recommend the Hypex Nilai, these sound like the best of the bunch to my ears
Thank you all for your responses. I was afraid I'd hear something like "f4 is endgame for me" which maybe shows me that quality-wise there still is no class D substitute for one of these class A beasts. I use my setup with a Khozmo "preamp" so transparency will be there... if it's in the source to begin with and if it's not gone in amplifications. Warmth is fine - did I mention I am getting old?
Running hot is a real problem. No, a human does not output the same amount of heat as a pair of class A monoblocks - the "scientific" test of holding a hand above my monoblocks and another one over my head instantly sets the score here. My house is so heavily insulated that listening to music in winter is a real part of my heating strategy 🙂
Does any D amplification even get close to class A? Am I going to curse my eco impulses when listening to vocals? Perhaps compromising here is the key - just getting something like this 3e-15se for summer and saving to build or buy a serious A-class beast in search for my endgame amp (honest: it will really not be easy to beat a pair of ACAs playing thru the goodmans horns).
Running hot is a real problem. No, a human does not output the same amount of heat as a pair of class A monoblocks - the "scientific" test of holding a hand above my monoblocks and another one over my head instantly sets the score here. My house is so heavily insulated that listening to music in winter is a real part of my heating strategy 🙂
Does any D amplification even get close to class A? Am I going to curse my eco impulses when listening to vocals? Perhaps compromising here is the key - just getting something like this 3e-15se for summer and saving to build or buy a serious A-class beast in search for my endgame amp (honest: it will really not be easy to beat a pair of ACAs playing thru the goodmans horns).
I can only give my opinions but I feel that class D has come a very long way , I love SETs and in certain ways, I feel that Class D shares many positive attributes of tube amps. I'm not 100% sure if they can compete in sound stage to some of the best tube or class A but I'm sure they are close. I will be buying one shortly. There are so many to choose from and I found out that you should not trust anyone's opinion, including mine.
People have been ranting about the AGD GaN amps , I was considering buying one , I heard them in the designers room, worst sounding room at the show these amps are mediocre at best, no life, no stage, and the owner was an ******* and clearly not an audiophile ( IMHO), the speakers they used where insanely overly bright, I can't understand how someone could set up a room that poorly, but again, clearly not an audiophile or listener.
The ice modules are just ok , the Purifi modules are decent, the one that stood out for me was the Hypex Mola Mola Perca but its like $10k+. I am 100% convinced that the Perca is a hot roded Nilai, with a better input board and some tweaks. I also heard the Nilai and it sounds very similar. It's interesting, the Nilai gets very nice reviews but the Perca is considered the best amp that many reviewers have ever listened to, I do not believe that these amps are that different. I'm pretty sure that the Nilai in a beautiful enclosure would also get stellar reviews. You can get an affordable DIY version of the Nilai, I will be getting one from Apollon audio . I highly suggest that you try listening for your self, there is a lot of hype going on, the latest model always seems to be the best and this is nonsense. I have been away from audio for 15 years and with my return, I realize that no one trusts their own ears, subjective evaluation is gone, people go by specs which is always secondary to how things sounds, trust no one!
People have been ranting about the AGD GaN amps , I was considering buying one , I heard them in the designers room, worst sounding room at the show these amps are mediocre at best, no life, no stage, and the owner was an ******* and clearly not an audiophile ( IMHO), the speakers they used where insanely overly bright, I can't understand how someone could set up a room that poorly, but again, clearly not an audiophile or listener.
The ice modules are just ok , the Purifi modules are decent, the one that stood out for me was the Hypex Mola Mola Perca but its like $10k+. I am 100% convinced that the Perca is a hot roded Nilai, with a better input board and some tweaks. I also heard the Nilai and it sounds very similar. It's interesting, the Nilai gets very nice reviews but the Perca is considered the best amp that many reviewers have ever listened to, I do not believe that these amps are that different. I'm pretty sure that the Nilai in a beautiful enclosure would also get stellar reviews. You can get an affordable DIY version of the Nilai, I will be getting one from Apollon audio . I highly suggest that you try listening for your self, there is a lot of hype going on, the latest model always seems to be the best and this is nonsense. I have been away from audio for 15 years and with my return, I realize that no one trusts their own ears, subjective evaluation is gone, people go by specs which is always secondary to how things sounds, trust no one!
"you should not trust anyone's opinion, including mine" - priceless!
"I have my oppinions, but I disagree with them" - said one of Dostoyevski's characters.
and, oh, specs! if it were for the specs, the ACAs should not play at all, yet they do.
Will try to listen to some contemporary class D in light of your experiences.
I have now this little caricature (class T they call it, but i think it's a Yamaha chip). Plays sufficient for background listening, when you don't concentrate on the music. But as soon as you focus you realize this sounds like a crank operated emergency radio... I might have exaggerated a bit there but you get the picture.
"I have my oppinions, but I disagree with them" - said one of Dostoyevski's characters.
and, oh, specs! if it were for the specs, the ACAs should not play at all, yet they do.
Will try to listen to some contemporary class D in light of your experiences.
I have now this little caricature (class T they call it, but i think it's a Yamaha chip). Plays sufficient for background listening, when you don't concentrate on the music. But as soon as you focus you realize this sounds like a crank operated emergency radio... I might have exaggerated a bit there but you get the picture.
Yep. they are making fans and made an amp by mistake.
This is how sick I am of my amps doubling as space heaters (music is on all the time)
...and there is some desperation here - hence the OP.
This is how sick I am of my amps doubling as space heaters (music is on all the time)
...and there is some desperation here - hence the OP.
I quite like the LM 4871 chip amp (class AB), only 3 watts but it works fine with 91db sensitive speakers.
There is no such thing as a class A sound.They vary as much in sound as class A/B.
The 15 watt Bakoon 7511 is a fantastic sounding class A/B SS amp and runs cool.Biggest bang for your buck in audio.
The 15 watt Bakoon 7511 is a fantastic sounding class A/B SS amp and runs cool.Biggest bang for your buck in audio.
Actually today, people go by 'reviews'. This is particularly unreliable as most (all?) reviewers are deaf (give less than consistent results in DBLTs).
I have tested this formally for nearly 2 decades and some of the important results are as follows.
- the "man-in-the-street" is more perceptive, gives more reliable results in DBLTs, than most HiFi Reviewers. There are (very few) exceptions.
- the "woman-in-the-street" is significantly more perceptive than the "man-in-the-street"
- da Golden Pinnae who hear differences between mains cables bla bla are all completely deaf, give completely random results in DBLTs
None of this is incompatible with generating marketing stuff. For reviewers and the last group, you say loudly & clearly, "our stuff is hand carved from Unobtainium & solid BS by virgins."
For the second point, pay close attention if your girlfriend, mistress, wife or mother says, "I don't like this new one as much as your old" of your latest pride & joy.
@kgrlee and @gdillon spot on: we all (hopefully) use our ears. As far as reviews are concerned - well, let me be the devil's advocate here. We do also chose by reviews, by more or less informed opinions, but still they are internet opinions.
This includes advice like the suggestions generously given above.
There is no way I will be able to borrow all the amps mentioned in this thread. Also, purchasing them and then returning using some store policy excludes... well... the very object of this forum: building. As well as other thrifty options like second-hand and so on. So, yes, if we have a community like diyaudio (that we trust to not be infected by hidden marketing) - it really helps.
Where I see the cancer is in the youtube/tictoc channels. I am getting so many wiim ultra video suggestions that it will end up convincing me not to buy it, just to spite this pushy marketing (it might actually be a great device).
Back to the amps - yes, trusting ears is important but trusting advice is irreplaceable. I might actually end up by postponing this choice for later - I seem to get that - as usual - you get what you pay for and I will not find amplification that is cold+good+inexpensive. Having "summer amps" that rival my "winter amps" and keeping both might not be a viable strategy. Either I should move to a better class A solution (a higher end First Watt), or a better AB solution (like the Bakoon), or a better D solution (Nilai?).
@danbmellow
Thank you for sharing this trajectory - I looked at the Elekit for a long time but decided against it.
By the way, an F4 is an unusual amp, does it not exclude using my passive pre (Khozmo)?
This includes advice like the suggestions generously given above.
There is no way I will be able to borrow all the amps mentioned in this thread. Also, purchasing them and then returning using some store policy excludes... well... the very object of this forum: building. As well as other thrifty options like second-hand and so on. So, yes, if we have a community like diyaudio (that we trust to not be infected by hidden marketing) - it really helps.
Where I see the cancer is in the youtube/tictoc channels. I am getting so many wiim ultra video suggestions that it will end up convincing me not to buy it, just to spite this pushy marketing (it might actually be a great device).
Back to the amps - yes, trusting ears is important but trusting advice is irreplaceable. I might actually end up by postponing this choice for later - I seem to get that - as usual - you get what you pay for and I will not find amplification that is cold+good+inexpensive. Having "summer amps" that rival my "winter amps" and keeping both might not be a viable strategy. Either I should move to a better class A solution (a higher end First Watt), or a better AB solution (like the Bakoon), or a better D solution (Nilai?).
@danbmellow
Thank you for sharing this trajectory - I looked at the Elekit for a long time but decided against it.
By the way, an F4 is an unusual amp, does it not exclude using my passive pre (Khozmo)?