Power Amp advice needed, for my JBLs 4312 power thirsty...

sorry for my weak explaining power...

first i build a stereo single ended, two holes in the chassis to fit two vu meters, one per channel.
ok, then i build a second block, and want to use the first as a monoblock....

can i leave the first block with two meters and the other one with just one ? 😀

come on :d
 
NO
No, as in don't do stereo, then monoblocks.

You have to be more tactical than this, your wife is going to kill you.

You start with monoblocks, then visually nothing has changed when you go to balanced.

Plus you won't have one monoblock with 2 VU meters and the other monoblock with 1 VU meter. Your wife will say your amp looks dumb if you do it that way. Hahahaha
 
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NO
No, as in don't do stereo, then monoblocks.

You have to be more tactical than this, your wife is going to kill you.

You start with monoblocks, then visually nothing has changed when you go to balanced.

Plus you won't have one monoblock with 2 VU meters and the other monoblock with 1 VU meter. Your wife will say your amp looks dumb if you do it that way. Hahahaha

good, i'll go for monoblocks, but you said to start single ended then go parallel as a final goal


now have to find out where to take the 12v for the vu meter driving board 😀

just need a toroidy with 4 outputs 😀

mmm and perhaps a loudspeaker bump relais
and perhaps a soft start
and perhaps a temperature monitor.
and/or a rail voltage monitor

😀 😀 😀
 
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Cool.

So MM Cartridge has between 3mV to 6mV output. Let's call it 4.5mV

With 44dB of gain we get to 720mV

Then 23dB of gain gets you to 10V rms

Another 6 to 10dB of gain could possibly be useful.
We can add a BA3 front end if necessary later. Just proceed as is for now.

My experience is that with a 2volt cd source and a power amp with 28db of gain, which is pretty average in the 100w class, a preamp with 10-15db of gain works well with most speakers. So 23db is going to run a bit low for a power amp with no gain. Using a higher than average sensitivity speaker will help, but you may find yourself with the volume control well advanced and not be able to drive the amp to full power with some lower level source material.
 
You certainly don't need any additional gain if you are using a DAC as your source

Don't worry, on my speakers that are 97dB, I have never needed more than unity gain from a DAC.
Just 2V rms.
I suspect you won't need much more than 4V rms.
 
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no sir, this is a mono phono preamp with variable eq for old records, you would refer to this
http://mmiworks.net/sprc/SP14-Nardi.pdf

but later, in the italian press, a new version with active cathode output stage (polarized with a led) has been published.
Line preamp is at the end of this article.

Do you have a link to the new version with active cathode output stage ?

I can read italian

Grazie mille