Hello all, I'm also a member of Lencoheaven where I bought a DIY amp kit sold in the traders section. I think it was developed by Aniket and offered by Sachu 888," Discrete Dynamics amp and pre-amp.After my build was completed Aniket suggested I change certain wires and use shielded wire.
Early in the build prior to any wire purchases I queried the need for shielded wire , wire gauge, silver or copper, solid or stranded. With no definitive answers I carried on.
I'm really very happy with the amp, the pre -amp has an issue with the vol. pot. so I have ordered a new one as per Sachins recommendation, I have given the pot a spray with contact cleaner and this did help in the short run, did not last.
Since I have to pull the Amp pcb to access the pre-amp I thought I would put shielding on any wire that needs it at this time. Don't want to replace wiring as I purchased quality solid core silver wire for hook up, just some basic guidance needed as I don't want do it twice.
Since this is my first post I'm not sure how to post pictures (can I?) to clarify things. Guess I can...cheers frothy
Early in the build prior to any wire purchases I queried the need for shielded wire , wire gauge, silver or copper, solid or stranded. With no definitive answers I carried on.
I'm really very happy with the amp, the pre -amp has an issue with the vol. pot. so I have ordered a new one as per Sachins recommendation, I have given the pot a spray with contact cleaner and this did help in the short run, did not last.
Since I have to pull the Amp pcb to access the pre-amp I thought I would put shielding on any wire that needs it at this time. Don't want to replace wiring as I purchased quality solid core silver wire for hook up, just some basic guidance needed as I don't want do it twice.
Since this is my first post I'm not sure how to post pictures (can I?) to clarify things. Guess I can...cheers frothy
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Found a thread for the power amp modules.
I do not see any of the usual ca. 1.5 µH output series inductors on these; you'll want to look up how to wind some of those yourself, it's not that hard. (Usually the ca. 4.7 ohm 3 W parallel resistor will fit straight through these.) I do see some ~3 W resistors, these might be part of the Zobel network (parallel R-C) together with some of the film capacitors?
Do you intend to keep the case open like that? Without extra ventilation, the amplifier would no doubt run hot.
Without knowing much about the specifics, every low-level audio connection shield use shielded cable. RCA to pot, pot to preamp, preamp to power amp. Avoiding ground loops can be a bit tricky... I hope either the power or the preamp board was smart enough to not connect its input ground to power ground directly but rather via a resistor or something... avoiding ground loops can be a bit tricky, but I think in your case you may have things on different power transformers anyway.
Also, transformer secondaries should always be twisted, especially those for the power amp. (As discussed by Douglas Self.) Can't hurt for the speaker connector wiring either. Speaking of which, that looks a bit thin - maybe 24 gauge or something? That would be about the minimum for up to 3 A of output current (75 W @ 8 ohms - real speakers may drop substantially below that). I would suggest something closer to 18 AWG / 0.75 mm², e.g. lamp cord.
In audio applications, either conductor resistance is largely irrelevant anyway (shield resistance still is of some interest), or you can just use marginally thicker copper wire. Given the same budget, a bunch of copper beats a little silver any day.
BTW, should you ever try to connect a computer to this one, it may turn into quite an ordeal chasing down the inevitable ground loop, as expected for an amplifier with unbalanced inputs built an an IEC Class I appliance.
I do not see any of the usual ca. 1.5 µH output series inductors on these; you'll want to look up how to wind some of those yourself, it's not that hard. (Usually the ca. 4.7 ohm 3 W parallel resistor will fit straight through these.) I do see some ~3 W resistors, these might be part of the Zobel network (parallel R-C) together with some of the film capacitors?
Do you intend to keep the case open like that? Without extra ventilation, the amplifier would no doubt run hot.
Without knowing much about the specifics, every low-level audio connection shield use shielded cable. RCA to pot, pot to preamp, preamp to power amp. Avoiding ground loops can be a bit tricky... I hope either the power or the preamp board was smart enough to not connect its input ground to power ground directly but rather via a resistor or something... avoiding ground loops can be a bit tricky, but I think in your case you may have things on different power transformers anyway.
Also, transformer secondaries should always be twisted, especially those for the power amp. (As discussed by Douglas Self.) Can't hurt for the speaker connector wiring either. Speaking of which, that looks a bit thin - maybe 24 gauge or something? That would be about the minimum for up to 3 A of output current (75 W @ 8 ohms - real speakers may drop substantially below that). I would suggest something closer to 18 AWG / 0.75 mm², e.g. lamp cord.
Looks like you have some audiophile nonsense to unlearn, my friend. Silver / silver-coated wire has its use in RF inductors when you're chasing the last bit of Q in an LC circuit, but the fact of the matter is that Ag has less than 10% higher conductivity than Cu while being much more expensive.
In audio applications, either conductor resistance is largely irrelevant anyway (shield resistance still is of some interest), or you can just use marginally thicker copper wire. Given the same budget, a bunch of copper beats a little silver any day.
BTW, should you ever try to connect a computer to this one, it may turn into quite an ordeal chasing down the inevitable ground loop, as expected for an amplifier with unbalanced inputs built an an IEC Class I appliance.
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thanks Sgrossklass appreciate your input, being a complete electronics neophyte this project was my intro to diy electronics. As mentioned in 1st post I put these questions of wiring out there well before purchasing any wire, getting no responses I proceeded anyways. Knowing many tone arms are rewired with silver TAwire I jumped to conclusion silver had to be good for signal wire in amp as well. Yes silver wire is expensive, but not over the top in the quantity used in this application and I really did want to achieve the best sound/outcome possible, to this end I used good to quality RCA's, speaker binding posts etc.figuring every little bit counts and adds up to a better end product.
This approach has rewarded me with tools that don't fail and items that can last for many years or a lifetime, no throw aways for the landfill for frothy (if he can help it!)
I have much to learn in this new endeavour (more than a hobby) very rewarding to have
something you have had a hand in creating.
yes I do play my tackle box amp with the lid open, played about 4hrs of LP's the other evening and the amps heat sinks were warm to the touch but I wouldn't call them hot.
You are correct there is so much information out there that it is difficult to discern what
is what , so many different opinions about all things audio, without personal experience it can be a daunting task to sort it out.
Again thanks frothy
This approach has rewarded me with tools that don't fail and items that can last for many years or a lifetime, no throw aways for the landfill for frothy (if he can help it!)
I have much to learn in this new endeavour (more than a hobby) very rewarding to have
something you have had a hand in creating.
yes I do play my tackle box amp with the lid open, played about 4hrs of LP's the other evening and the amps heat sinks were warm to the touch but I wouldn't call them hot.
You are correct there is so much information out there that it is difficult to discern what
is what , so many different opinions about all things audio, without personal experience it can be a daunting task to sort it out.
Again thanks frothy