if someone could be patient enough to explain, then I would like to know the difference between the RevA and RevC and can we convert Rev A ( stereo Board ) to Rev C, I do understand we would have to manage to solder the components for the change. but is it possible?
Thank you, I m going with my build a little slow.
Bought the 0.1% resistors and ordered other components awaiting delivery...
also working on a PGA2311 with Relay for input selection.
Regular work is taking a lot of time from me and leaving a little while to relax but going on with the build ( this build is getting a bit expensive for me 😀).
Bought the 0.1% resistors and ordered other components awaiting delivery...
also working on a PGA2311 with Relay for input selection.
Regular work is taking a lot of time from me and leaving a little while to relax but going on with the build ( this build is getting a bit expensive for me 😀).
I have been listening to the amp since couple of days. I like it.
Need to find a suitable cabinet in india and not too expensive.
cool amp. Doesn’t heat up more than being a bit warm at my listening levels on 8ohm load.
also need a input switching circuit with remote ( no tone control).
Help on the cabinet would be great
Need to find a suitable cabinet in india and not too expensive.
cool amp. Doesn’t heat up more than being a bit warm at my listening levels on 8ohm load.
also need a input switching circuit with remote ( no tone control).
Help on the cabinet would be great
I'm going to start my own amplifier design, these modifications will move it even more into the High End class
- It will be implemented as a pure monoblock (moduschop)
- 200W toroid (talema) + 2x 22.000uF / for 1 channel
- I will replace the zener diodes for lm318 with stabilizers LM317/337
- the value of the input capacitor is increased to 6u8
- The original rev c scheme will be retained
- The 0.47ohm/7W output resistor will be replaced by a metalized 0.6w (10x 4,7ohm parallel)
then you'll want to have a look at the "Fremen Edition"... no need to reinvent the wheel. 😉
https://www.diyaudio.com/community/threads/my_ref-fremen-edition-build-thread-and-tutorial.234032/
https://www.diyaudio.com/community/...dition&t=post&c[title_only]=1&o=relevance&g=1
Yes, I'll give a positive vote to UnixMan's suggestion. The Fremen edition, now in V1.8, is a sonically beautiful implementation of M Penasa's design. The BOM ranges from "frugal build" to "audiophile build." It's one of the best sounding LM3886-based amps out there.
Cheers
After years I've decided to build the RevC. last year, thanks to recent mandates. I'm not a pro, just the basics. But I have a very uncommon issue. I have a 180 degree phase shift between amps. It's very obvious, no doubt. Over software I shift the phase of one channel and we're back in business. Interestingly this shift is not present with a 4ohm load, different speakers per se. But 8ohms, phase shift! It's almost perfect to where I can flip the polarities of one speaker. Other than this discreetly the amps work just fine; no hum no noise, just perfect. By Mauro's (RIP) pdf's I'm guesstimating it's one of the compensation networks. All resistors are .1, caps are far from perfect. I'd be glad if someone can point me into the right direction before I start flipping parts.
Nevermind, thought I've checked the cables gazillion times from the board to the chassis, wondering how a perfect phase shift could even happen by compensation... but I had nothing left. One of them shrodinger moments.
Guys need a small help - what is the trigger level ( + /- ) for the protection circuit. and we we use it for a transistorized amp or is it designed only for my ref
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If I remember correctly the speaker protection kicks-in at 1.5V DC
If your needs are the same, sure it can be used on other circuits.
Hi @ClaveFremen
I tried to simulate the circuit but it turned on at 5volts
So could you confirm at you end if it works at 1.5 or is there some documentation?
It will great help.
Or if you or someone could guide how to test it on LtSpice which commands to use?
I tried to simulate the circuit but it turned on at 5volts
So could you confirm at you end if it works at 1.5 or is there some documentation?
It will great help.
Or if you or someone could guide how to test it on LtSpice which commands to use?
I can confirm that it's more than 1,5V. The exact value I don't remember, too...
My assumption is that here Mauro had tried to optimize between a still practically acceptable level and a safe dynamic headroom so as not to intervene too fast with real music.
I can confirm that it works quite well in practice. it's rare that the error would manifest like a 4V DC stable level ..
Are there in circulation other, more precise circuits? Today I would say yes.
Other 'feature' of the MyRef protection circuit is the insensitivity for negative polarities..
My assumption is that here Mauro had tried to optimize between a still practically acceptable level and a safe dynamic headroom so as not to intervene too fast with real music.
I can confirm that it works quite well in practice. it's rare that the error would manifest like a 4V DC stable level ..
Are there in circulation other, more precise circuits? Today I would say yes.
Other 'feature' of the MyRef protection circuit is the insensitivity for negative polarities..
Any suggestions for both positive and negative sensing protection circuit.
There are just too many, not looking for SS ones
There are just too many, not looking for SS ones
something is wrong coz I do not see reply button below the posts in the thread
I am replying via mobile - did I hurry anyone than sorry
Ohhh my bad - I need to use “Quote”
Sorry
I am replying via mobile - did I hurry anyone than sorry
Ohhh my bad - I need to use “Quote”
Sorry
