That is a bit too unspecified..
But to answer your question, my guess would be a class A amp. Pass/Hiraga/JLH/Krell clones.. there are many.
-IF you are happy with an expensive build(big transformers/heat sinks/cap-banks..), a few watts output and a lot of wasted heat?
But to answer your question, my guess would be a class A amp. Pass/Hiraga/JLH/Krell clones.. there are many.
-IF you are happy with an expensive build(big transformers/heat sinks/cap-banks..), a few watts output and a lot of wasted heat?
Ah. Yes, I should have said amplifiers around about 100 Watts.
By the time you’ve factored in the cost of casing the project up etc. A 200 Watt amplifier with stacks of headroom isn’t such a bad idea.
The modules from Holton look good. I haven’t found any alternatives.
By the time you’ve factored in the cost of casing the project up etc. A 200 Watt amplifier with stacks of headroom isn’t such a bad idea.
The modules from Holton look good. I haven’t found any alternatives.
Holtons modules are really nice, Anthony is a member here so guidance is no problem.
But look in audio store here, honey badger is also a option
But look in audio store here, honey badger is also a option
Leach LowTIM and the Mooly Mosfet amp are my favourites, but it also depends on the parts used (particularly in the PS) and the layout.
The best sounding? Your question is a religious argument, IMO none of the amps mentioned qualify as they are not class A. Watts, sound quality, cost....pick the most important 2 because you cannot have all 3. For the best sounding diy in the 100w range you can build pass F4 or F5t mono blocks (great documentation and support but expense and difficult). If you leave class A consider the hafler 200/220 mod thread on this site, I believe they will have modern hafler clone boards available soon, the sound quality on these is very high.
I agree.
I disagree. Pass stuff is great for hifi aspects of sound, but poor in terms of coherence and musicality.
Class A, single ended, zero global feedback etc. are all red herrings IME.
Wow that’s not a religious argument that’s blasphemy! I could not disagree with you more, i have owned dozens of amplifiers and most of the time my pass designs define musicality. If class A or single ended are red herrings for you how do you feel about tubes?
Wait feedback? Feedback is somewhere between a design/designers crutch and a magic trick with no magic.
It’s all subjective though, whatever makes your ears happy....
Choose a quiet amp with flat frequency/phase response across audio band and good damping and < 0.01% distortion (of all kinds into a realistic reactive load). Should sound as clean as any other. And of course make sure its got enough headroom for the relevant room/speakers/listening volume.
Good thermal stability is important for class B designs, as fluctuations in bias point with dynamic content is not easy to assess from standard measurements/specs. This suggests not skimping on heatsink size.
Good thermal stability is important for class B designs, as fluctuations in bias point with dynamic content is not easy to assess from standard measurements/specs. This suggests not skimping on heatsink size.
Tubes (or valves, over here) are fine. I have a KT88 PP amp which is pretty good.
The biggest issue with valves is that to a degree no 2 sound alike. So most of them must be wrong!?!
Feedback is an extremely useful and powerful tool to improve performance.
Try to run all the motor drives that control the motors in our factories without feedback and see if you can make anything within tolerance.
Then consider that a motor and a louspeaker are not all that different.
For 100 watts+ then it needs to be class AB.
So its China, ebay or another online retailer.
China and ebay are a lottery in regards to quality/fakes so I would recommend online retailer.
So its China, ebay or another online retailer.
China and ebay are a lottery in regards to quality/fakes so I would recommend online retailer.
Krell models, their imitators and DIY clones are, technically speaking, class A but use several sophisticated forms of sliding/switching bias to do so with much less heat dissipatation. Thus, you can have class A at even more than 150W but then you are also looking at serious complexity and construction costs which may well exceed the price of used models and still require many hours plus good construction skills and equipment to ensure reliability.
If cost is no object, this may be the ultimate path to DIY sound quality for your ears but first, you need to be familiar with the products and their performance to make decisions on the type of design and actual power level needed. It's surprising how little power is produced at "10 o'clock" on a 100W amplifier and this is often a level which I find users are listening at. Most of my integrated amplifiers and occasional repair jobs, which include 100W+ commercial products, are lucky to peak at 5W/8R on that nominal setting.
A 50W amp is still plenty of overkill in typical domestic use but DIY covers a lot of applications including professional ones. Some folk also have vast areas to fill with sound. Perhaps they also have really inefficient speakers, like to throw loud parties or maybe just can't wait to demo their handiwork as more powerful than what you can buy in a box store. Even 200W may not be enough if you let imagination take over your wants list.
If cost is no object, this may be the ultimate path to DIY sound quality for your ears but first, you need to be familiar with the products and their performance to make decisions on the type of design and actual power level needed. It's surprising how little power is produced at "10 o'clock" on a 100W amplifier and this is often a level which I find users are listening at. Most of my integrated amplifiers and occasional repair jobs, which include 100W+ commercial products, are lucky to peak at 5W/8R on that nominal setting.
A 50W amp is still plenty of overkill in typical domestic use but DIY covers a lot of applications including professional ones. Some folk also have vast areas to fill with sound. Perhaps they also have really inefficient speakers, like to throw loud parties or maybe just can't wait to demo their handiwork as more powerful than what you can buy in a box store. Even 200W may not be enough if you let imagination take over your wants list.
What is meant by DIY “module”? A pre-assembled amp ready to be connected to a PSU, heatsink, and input/outputs? Or a does a PCB and BOM count?
There are a lot of DIY amps on this forum that are good or great. I don’t see too many preassembled ones though except what is sold on eBay and AliExpress as clones of some commercial design. The thing about the Chinese clones - you don’t know how faithful they are since they are reverse engineered. I have seen products that have layout errors yet continue to be cloned by guys cloning clones! The astute commercial amp designer will have “clone traps” (purposely installed anti forgery traps) built into the design and schematic so that someone reverse engineering it will fall for the trap and make a dud.
You might want to try the newest Class D amps like the TPA3255. They can give clean neutral response over 100w with low distortion with great dynamics. At average listening levels of say 10w to 25w, I measured around 0.001%THD. They are 90% thermally efficient too so they don’t heat up the house. You will need to get one with post filter feedback (PFFB) if you want the lowest distortion.
There are a lot of DIY amps on this forum that are good or great. I don’t see too many preassembled ones though except what is sold on eBay and AliExpress as clones of some commercial design. The thing about the Chinese clones - you don’t know how faithful they are since they are reverse engineered. I have seen products that have layout errors yet continue to be cloned by guys cloning clones! The astute commercial amp designer will have “clone traps” (purposely installed anti forgery traps) built into the design and schematic so that someone reverse engineering it will fall for the trap and make a dud.
You might want to try the newest Class D amps like the TPA3255. They can give clean neutral response over 100w with low distortion with great dynamics. At average listening levels of say 10w to 25w, I measured around 0.001%THD. They are 90% thermally efficient too so they don’t heat up the house. You will need to get one with post filter feedback (PFFB) if you want the lowest distortion.
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My system has barely made any strides forward for 20 years apart from adding an Arcam rDAC a couple of years ago and that became redundant when I bought a Bluesound Node 2i three months ago.
My amplifiers are two Audiolab 8000M mono amplifiers. I really do not know if a significant improvement would be made by building an amplifier to replace them. I built a low noise psu for the rDAC and a passive volume controller using an Alps Blue potentiometer so I am a confident builder.
My speakers are Kef 105.2 that I bought from a Television studio in maybe 1984. I paid £285 for them.
My amplifiers are two Audiolab 8000M mono amplifiers. I really do not know if a significant improvement would be made by building an amplifier to replace them. I built a low noise psu for the rDAC and a passive volume controller using an Alps Blue potentiometer so I am a confident builder.
My speakers are Kef 105.2 that I bought from a Television studio in maybe 1984. I paid £285 for them.
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8000M’s are 125w 8ohms with 500VA toroid, Sanken BJTs in push pull. Nice amp. Unless you want to have SE Class A amplification - I am not sure you will be able to do much better. The 8000M’s are probably traditional LTP input stage so might be third order harmonic dominant. Brighter sounding than smooth sweet second order SE Class A. But that is a matter of taste. The KEFs in general are low impedance loads despite their “8ohm” labels. So an amp like this might be perfect since getting a SE Class A amp to drive 4ohms means more heat.
Thanks xrk971. That’s really useful information.
I would say my system is on the dry and detailed side. It’s what I have got used to over a very long time. It would take some getting used to if it became too warm or too dynamic.
I would say my system is on the dry and detailed side. It’s what I have got used to over a very long time. It would take some getting used to if it became too warm or too dynamic.