Honestly, I have no idea how well changing out the A56 and A06 with other devices will work. Quite possibly it will make little difference. On the other hand, it could introduce instability. I know my technical advisor would ask “what do you hope to gain” in making a change to a proven, tested design. At a minimum you must verify that stability and distortion have not degraded. She would say her time is better spent taking a nap…
A good topology is pretty forgiving of minor variations in device characteristics. So substitutions of parts generally have only minor effects.
A long time ago, I decided to simply ignore people asking me to spend time incorporating whatever device they were keen on, as I knew it would only make a very small difference for significant effort. It's easy saying "have you tried blah part", but without actually trying blah yourself you're not really making much of a contribution, and tasking others with trying it because you don't want to expend the effort yourself is simultaneously arrogant and lazy.
Much more interesting is changes to topology, as that's where big gains come from. By far the most interesting thing I've done with this amp is the folded cascode that I incorporated for the class G version. Unloading the first stage speeds it up significantly, and really improves the distortion performance without stability issues.
A long time ago, I decided to simply ignore people asking me to spend time incorporating whatever device they were keen on, as I knew it would only make a very small difference for significant effort. It's easy saying "have you tried blah part", but without actually trying blah yourself you're not really making much of a contribution, and tasking others with trying it because you don't want to expend the effort yourself is simultaneously arrogant and lazy.
Much more interesting is changes to topology, as that's where big gains come from. By far the most interesting thing I've done with this amp is the folded cascode that I incorporated for the class G version. Unloading the first stage speeds it up significantly, and really improves the distortion performance without stability issues.
I would like to thank you. We, as diyaudio producers, are following the path of good diy artists like you. I am currently listening to the 50w r2 version you designed and it really sounds good to my ears, so it deserves to be boxed. In general, the jfe2140 is the one I liked the most from the jfetlers I listened to, I also made a PCB to evaluate my sleeping nichicon capacitors and selected exicon mosfets in my drawer. I have been liking dc amplifiers since I started to deal with these things. I would like to thank cyberpup for the jfe2140 and servo version of your amplifier.
question:
at suzyi amp the R46 (zobel network) is a 3W wirewound implemented.
at cyberpup Myka SJ R46 is about 1W. ...e.g. MMB02070C1209FB200
just 1Watt?
i have the Myka SJ pcb and i plan rail voltage 34-40V
at suzyi amp the R46 (zobel network) is a 3W wirewound implemented.
at cyberpup Myka SJ R46 is about 1W. ...e.g. MMB02070C1209FB200
just 1Watt?
i have the Myka SJ pcb and i plan rail voltage 34-40V
If the amp is behaving the zobel dissipates stuff-all. If it's oscillating you'll burn your finger whatever resustor you use.
if you are talking about the amplifier board, it is ready to work. you just need the transformer, psu and heatsink.
You get first price !🙂!
More seriously, DIY amps are never about saving money.
Suzyj published a BOM: this should give you an idea.
guys, i know a lot of things, but about amplifiers and boards, valves and connections, very little, but i learn quickly.
every info you give me is precious to learn.
every info you give me is precious to learn.
morning
We all know that housing and PSU is the more expensive part of the amp. and maybe a SSR too.
kr
chris
We all know that housing and PSU is the more expensive part of the amp. and maybe a SSR too.
kr
chris
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at post 314: here post 314
we get from Cyberpup a nice example to use a Modushop Mini dissipante 2U 250mm.
he did some minor changes a desiged PCB Myka SJ and Myka MK6 (DC offset and additionalle BJT as VAS driver)
at post 119 : here post 119
we get a nice try to use a very small 1U slim case also by modushop
so the money you want to spend is not just buy some modules. its personally design , psu, bias current, power you "need "
---> this is engineering
kr
chris
Some amplifiers are worth spending money on. Some of them for me; Parallel tda7293, LM4702 LME49830 and AEM6000. 2x Amplimo 2x35V 300VA transformers for AEM6000 only 240€....
I think that it would be technically beneficial to put all the transistors in the same heatsink and work with equal heat in AEM6000. I also think that the mids of this circuit, which are great with sst404, will be even better with JFE2140. It will be a good amplifier with DC and short circuit protection, soft start and ac filter.
I think that it would be technically beneficial to put all the transistors in the same heatsink and work with equal heat in AEM6000. I also think that the mids of this circuit, which are great with sst404, will be even better with JFE2140. It will be a good amplifier with DC and short circuit protection, soft start and ac filter.
