wowsers! Lots of different cables/wires in 1 gainclone!

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Hi all

Iam preparing for my first diy gainclone project. What strikes me is that, although it seems everyone takes cables and wiring very seriously, I can't find good information on which cables/wires to use where. When i look at pictures of fixed gainclones, i see all sorts of wires and cable differences between different projects, and lots of different types of wires within one project. I have to say: iam a complete beginner, so maybe my question is too stupid, in that case forgive me. I have tried to come up with some sort of schematic of different components in a gainclone and the wires/cables between them (see picture).
You see cable 5e and 5i. iam not sure wether my transformers are gonna be intern (5i) or in an external casing (5e), hence the two types.
I would really appriciate your input on what kind of wires to use where (type/material/size). I probably forgot some too, pls let me know.
Eventually I would like to have/publish here a document/scheme for other newbee's like me to use when they are starting projects like this.

tnx a lot!

Erik
 

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Being a value oriented kind of person, I use 23 gauge solid core copper or silver coated copper for signal wires, and 18 gauge stranded copper for speaker and short runs of power wire. For the longer connection between my power supply and amp, I used an IEC 320-C19/IEC 320-C20 cable with 14 gauge wire.
 
Hi,
I don't know what measurement systems you understand. I will stay with mm since we are metric.

Signal wires: twisted pair of solid 0.4mm diam to 0.6mm diam.
Speaker wires: twisted pair of flex 1sqmm to 3sqmm.
Power wires: twisted pair of solid or flex 1sqmm to 3sqmm.

Everything copper or tinned copper (not tin plated). At this stage don't get involved in 6 9s nor silver nor silver plated nor Litz nor carbon, nor any of the other exotic materials.
 
One of the beauties of an IC power amp in the first place is they are so small that if you do it right you don't need much wire around them. I know there are a lot of people that hate this truth, they gotta have a couple thousand bucks between their amps and speakers or it don't sound right to them, but the best sounding wire isn't. It's an age old problem that the signal source isn't where both speakers need to be, but inside the amplfier, if you wanna go all hi-end on this thing, try getting the terminals and attenuator as close as possible.
 
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... if you wanna go all hi-end on this thing, try getting the terminals and attenuator as close as possible.

Sensible thought. Crossed my mind, but Iam having practical problems: this would mean a volume/attenuator and input selector per channel right? That does not seem to practical in case of the input selector, and pretty difficult for the infra red remote controlled volume potmeter I have in mind (not to mention the fact that that itme is about the most expensive part of the whole amp).

Would there be ways around this, cause i would love some cool looking amps just underneath my Anthony Gallo Nucleus micro speakers...
 
Erik

The usual way of doing this, is to mount the volume pot on a bracket at the rear of the amp. Use an extension shaft to connect the pot to a knob on the front panel. You could do the same with a rotary input selector.
This way, low level signal wires which may be susceptible to interference can be kept short. Not so important with speaker wires, in my opinion.

If using a remote control volume pot, could the sensor be on the front panel and the pot at the back?
If not, just use screened cable and keep well seperated from mains and transformer wires. This might be all you need to do.
 
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... if you wanna go all hi-end on this thing, try getting the terminals and attenuator as close as possible.

Iam getting confused a bit...

Do you mean getting the amps close to the speaker (as I thought) or internally the wires from the volume/input selector to the amps as short as possible (as Trebla seems to be suggesting)?

Both make sense to me, but that is just me!
 
Hi,
a stage with a low output impedance and adequate current capability can usually drive any cable attached to any input.

A stage with a high output impedance or with low current capability cannot drive capacitance well. This prevents it being used with long cables.

A 20k volume pot has an output impedance of zero ohms to 5000ohms depending on it's setting. This cannot drive long nor medium length cables. It must instead be connected with short or no cables to perform at it's best.

Adding a buffer to the output of most medium to high impedance output stages generally converts that stage to be able to drive long cables.
 
use .......... short cables after {every low current source} or add buffer. Does the quality of the cable influence the possible length? And to round it off: short means less then ... cm/inch?
for audio, short is probably around 500mm to 1000mm depending on what is at either end.
Quality is not usually the issue, copper is, well just copper.
It is the cord/cable parameters that vary and should be chosen appropriately.
 
Erik,
I just meant that doorbell wire would be good enough if you kept it short and twisted pair for all possible differential current paths. (which they all are, you know, just some aren't as easy to twist together as others) As it must get longer then quality and gauge becomes more important. Two channels of LM3886 really don't even need a 17 or 19" rack cabinet. Unless you are seriously into convention I'd recommend having the input as close to the output terminals as possibe with as little in-between as possible. For all intents and purposes they are right next to each other in the chip, there's no good reason to add reactance if not necessary. You should see the size of the wire used to connect the chip to the leads on the package.
 
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Most LMxxxx chip designs have a inductor/resistor network on the output that makes them exceptionally robust against any kind of amp-to-speaker wiring. Even the really exotic cables made of 98% crystal-aligned cross-woven Kryptonite and Dreamy Nativity.

18AWG lead are plenty to wire up less than 10cm internals. You can tightly twist twin conductors together to achieve the same EM suppression shielded wire enjoys. Ordinary copper wire is just fine: the distances involved here are so small that the difference between figure-8 bell cable (10c per meter) and solid silver ($a lot) would be almost impossible to measure - you could probably wire together a chip-amp project with particularly sticky spit and the audio-frequency bandwidth performance wouldn't be measurably, let alone audibly, different to OFC, silver or anything else.

At least start with something simple and if your curiosity and bank balance is up to the job, make a MK II with more exotic ingredients and see how it compares.
 
Just wondering - why are people still building gainclones, when there are Tripath TK2050 boards for 30 euro that are just better in every way? I built two GCs and none of them comes close to TK2050 :confused:
While off topic, trolling and not useful to the original question, the answer to that is

1) Tripath is bankrupt, does not manufacture chips any more and was, even when they were in full production, hard to find in many parts of the world (not to mention the increasing difficulty of getting replacements should a fault occur as worldwide stock diminishes),

2) many people have tried and said they prefer the LMxxxx sound. Opinion is a wonderful thing! The extreme high end of sonic appreciation is, like wine tasting, contemporary art, good tea and designer wallpaper, a particularly unreliable and subjective area (often belonging to people with more willingness to spend money on idle whims than strictly healthy for the species),

3) 'every way'? Impossible! Show me a chipamp project that gives you fresh coffee in the morning and I'll think about changing my mind (more or less).
 
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