Thanks some doc how i need to use the PSU kit board if use 1 transformer or if use 2? i dont remember very well the configuration! i have the pdf that come with the kit, but dont say anythong abt that.
As i say i have two 23-0-23 will try to test using one and using two!
With two transformers you will have 2 completely separate mono amps, so you use both rectifier boards and most likely you will need to order aditional rectifier set, as ea kit comes with a single rectifier set.
With a single transformer powering a stereo amp, you will only use a single rectifier board and split power wires to both amp channels.
With a single transformer powering a stereo amp, you will only use a single rectifier board and split power wires to both amp channels.
The only sensible reply I can give you is that we will sleep better if you first do it and then ask questions
Thanks, that's exactly what I did, no more questions needed. The result was total silence even with my ears right up to my speakers which are quoted at 97.3dB. I must admit I was very happy considering how i had taken something so simple and made it so complicated! There is still time for problems though, its not finished but it is running as pictured.
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Just installed the Gainclone using Peter's LM3875 Premium Kit, it's a stereo version with volume pot per Peter's building instruction including signal and power ground.
Everything works great except the hum when I connect an audio source to the RCA input and the audio source is on, if I turn up the pot, more hum produced. However, once the audio source is disconnected or turned off, there is no hum at all.
Per local practice, the AC power is unearthed (i.e. only live and neutral but no earth), therefore, my Gainclone is not really grounded. It's uncertain whether this is the cause.
Any suggestion and help to address this hum issue is much appreciated.
Everything works great except the hum when I connect an audio source to the RCA input and the audio source is on, if I turn up the pot, more hum produced. However, once the audio source is disconnected or turned off, there is no hum at all.
Per local practice, the AC power is unearthed (i.e. only live and neutral but no earth), therefore, my Gainclone is not really grounded. It's uncertain whether this is the cause.
Any suggestion and help to address this hum issue is much appreciated.
Yes. I am using a metal enclosure. The PG and OG are connected together then connected to the enclosure ground connector as shown in the attached picture.
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Thanks Samsagaz, I regret using the fire proof silicone to stick the caps to the chassis but I was expecting more heat than im getting.
Dont know if it helps but i didnt ground the return on the volume pot which it looks like you have, I just connected input and output returns to the RCA's.
Im sure someone who knows will help but if you have no earth connection in your country should you be connecting grounds to the chassis? whats the point of the safety earth connection on your IEC input? just curious.
Alan
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Yes, Per #44 of http://www.diyaudio.com/forums/audio-sector/123003-commercial-gainclone-kit-building-instructions-5.html#post1516302, I grounded both ground return on the pot and ground of RCA to SG. I will try your suggestion and see if it works.
In some Asia countries, we use Type A 2 pin power plug ( Power plug & outlet Types A & B - World Standards).
It looks weird, but we don't ground most electrical equipment except wash machine and refrigerator, etc. Therefore, the earth connection on my IEC is unearthed.
I am using these for all my little projects, bargain if you ask me. DACT Type 21 Stepped Attenuator Potentiometer 10K * D shape shaft * | eBay
I wont be using it long term in this set up but Ive got them in other projects and i am very happy with them.
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The wires from commont point to OG pads create two large loops, maybe this is a problem?
I would do it like that: run common wire between both channels OG pads, from the center of this wire run two wires to binding posts, and from rectifier board the PG wires also to this central point (don't run it around heatsinks, but drill a hole and run it through it). This will create sort of a cross, without any loops.
nice!
i found a few, which will be the diference if use 10k, 50k or 100k potentiometer?
What about the ones with dale resistors? 2016 YY 65Y Dale 23 Step Attenuator Volume Potentiometer 10K | eBay
will get the same result?
I wouldnt be surprised if those dales are fake, it seems nothing is safe, at least with the DACT theres nothing to copy, except maybe the good name, i prefer short signal paths and gold plate to silver so i would get the cheaper pot. as far as which value, out of the 3 avail 10k would be the best choice for Peters 3875 kit. I use a 50k on a modified 3116 and the 100k on my kt88. Buy them all, there silly money for the quality, unless anyone else has had issues?
Ive just read an old post and peter says 25-50k, maybe its more critical on less sensitive speakers, the 10k im using is fine with mine which are a little over 97dB, Im sure ive seen 10k recommended before.