This is not just another gainclone

[Fred Dieckmann]

"I have some Elna Cerafine 100uF / 25V ROA series. Can I use those somewhere in my gainclone? Like bypassing the 1000uF standard caps I use...?"

I would not put 25V caps on a 35 Volt supply in less you put two in series with a 10K resistor divider to half the voltage across them. I tried 100uF Cerafines across some Nichicons and was pretty unhappy with the sound. I don't understand the cult following that the Cerafines have. A designer who's ears I trust descrided them as "Shouty". I found them grainy and veiled sounding sounding as supply bypass caps. The Black gate 100uF Stadard series sound like a completely different amp and were much so better at high frequency focus and dynamic contrast.
I think even the Panasonic FC might be an improvement over Cerafines.

[2Bak]

Originally posted by Fred Dieckmann

I tried 100uF Cerafines across some Nichicons and was pretty unhappy with the sound.

Thanks.
I have never heard those Cerafines in any application myself, just wondered if they could do something nice for my gc. I'll drop the idea and in fact I'm really happy with my gc as it sounds now...

Can I follow-up here:
My gc is three-channel poweramp, and I want to expand it into a five-channel version to be used as combined stereo and cinema amp.
This one uses standard Jamicon 1000uF caps. I want to make those two extra channels better than the other three channels, since I'll be using them for stereo on a regular basis.
However I cannot at the moment afford to buy those Black Gates.

Are there any alternatives to BG 1000uf? Would those Panasonic FC's be the best bet?

[Peter Daniel]

You might also try Nichicon KZ which at 1000/50V cost only $2.15.

[Bricolo]

Why do WIMA MKS4 sound bad?
I've got a pair of MKS2 4.7uF laying here, waiting for being soldered to my gainclone's input


don't tell me they don't sound good, I payed them 3€ one

[Bricolo]

I tested the amp with a friend's oscilloscope



on a dummy 5R load (made with 2 1/4W 10R resistors) the signal is nice clean
even when we push the volume, the signal is clean.
at 100% volums it was still clean, untill the 1/4W resistor began to smoke (it didn't like 40W )



the power supply lines have 25V DC, plus an AC signal, like sawtooth, but with a vertical section and a non vertical one, 300mV p-p, 100Hz


some noise on the output, with no signal, but <20mV




now the bad part of the news:
when connected to a speaker, and a sinusoid denerator (computer based (the computer's output is a clean sinudoid)

the signal is good at low volume, but at higher volume, the sine's top peak is a big filled circle

[fedde]

Originally posted by Bricolo
Why do WIMA MKS4 sound bad?
I've got a pair of MKS2 4.7uF laying here, waiting for being soldered to my gainclone's input

don't tell me they don't sound good, I payed them 3€ one

Hmmm... I paid around 20 eurocent for my 2.2 uF MKS4 I think. And I think it sucks more or less. Well, I just don't like it. MKC4 is much better, and very probably MKP10 too. Sorry...
But maybe MKS2 is good... just try it!

Fedde

[fedde]

Originally posted by 2Bak

Are there any alternatives to BG 1000uf? Would those Panasonic FC's be the best bet?

Panasonic FC sounds quite OK! (I did not try others, but I think it sounds ok this way). They cost a little more than 2 euro. Maybe you can find it cheaper.

Good luck,

Fedde

[mrfeedback]

There is much good information here by the likes of Peter, Fred and many others regarding sonic influence of transformers, rectifiers, caps, diode snubbing networks etc..

One tweak that I have utilised in the past is to put RC snubbing networks across the main supplies.
I found this to noticeably 'quieten' the amplifiers that I tried it on.

Eric.

[Bricolo]

who else has checked it's PS rails with a scope?

[Nuuk]

One tweak that I have utilised in the past is to put RC snubbing networks across the main supplies.

Another option that I use on my present power amps, is a tranzorb and voltage dependent resistor in series across the live and neutral wires.