Hi guys,
I built this simple power amp, 125w, first upgrades were changing the cheapy caps for Elna Silmic II, better power caps, hardwired input and output, hardwired dac everything is direct.
Now the only things I can think of trying next is an oversized transformer and increasing the rating of the power caps and using Mundorf M Lytic.
Can anyone suggest some other upgrades to these two modules, I cut out and bypassed the output coil but this is an older photo. The amp sounds stunning, just needs a bit more bass and low mid-range.
Thank you!
I built this simple power amp, 125w, first upgrades were changing the cheapy caps for Elna Silmic II, better power caps, hardwired input and output, hardwired dac everything is direct.
Now the only things I can think of trying next is an oversized transformer and increasing the rating of the power caps and using Mundorf M Lytic.
Can anyone suggest some other upgrades to these two modules, I cut out and bypassed the output coil but this is an older photo. The amp sounds stunning, just needs a bit more bass and low mid-range.
Thank you!
Attachments
So going ahead and building a new power supply board with Mundorf mlytic and putting in a bigger power transformer as someone recommended on another thread.
Here's a better pic of the power amp. Anyone have any suggestions for upgrades to the amp modules?
Attachments
I'm still a beginner how do I tell? All I know is they're IRFP something? Sorry I'm only a year into the hobby so need help with some real basics.
So those are known as vertical mosfets.
I know that circuit was made with the older lateral mosfets at one time. I have no experience with the type you have, so can’t add anything.
Something you can do to help the power supply is to use what’s called a snubber circuit on the rectifier bridge. It reduces the shot noise from the power supply diodes switching action from then interacting with the inductance of the transformer.
And this is just assuming you have a linear power supply with those components…
Can search for “snubber” for more info.
There are some great discussions on optimization using testing, however, I have found that the values of .01uf, and .1uf + 18ohms works quite well.
I know that circuit was made with the older lateral mosfets at one time. I have no experience with the type you have, so can’t add anything.
Something you can do to help the power supply is to use what’s called a snubber circuit on the rectifier bridge. It reduces the shot noise from the power supply diodes switching action from then interacting with the inductance of the transformer.
And this is just assuming you have a linear power supply with those components…
Can search for “snubber” for more info.
There are some great discussions on optimization using testing, however, I have found that the values of .01uf, and .1uf + 18ohms works quite well.
Thanks for the help! Are lateral mosfets OK for audio? The amp is hardwired (hardwire soldered both ends) to a nice Schiit Modi DAC and sounds beautiful but I'm obviously keen to upgrade.
its the hitachi app circuit, but its for LATERAL FETS
lateral fets have different pinouts so "simple" swap it not possible
here is an article about irf fets
lateral fets have different pinouts so "simple" swap it not possible
here is an article about irf fets
So another noob question regarding this power amp circuit. Why doesn't it have bias pots? Is that unusual? It sounds fantastic after a few tweaks but a few things about it make me wonder.