Build a dedicated Audio PC

[nige2000]

Sorry I'm late for the party! ;-)
Recently I followed only MQn tread, until Tony brought this to my attention.

Yes there is a full 3M AB-5100S under MoBo and on the inside of each "chamber" (not in the picture). Grounded copper is more to prevent the interference between the PC components and 3M is to absorb it, so EMI does not get bounced back. That was my understanding after I read a thousands of posts!
I believe that copper will be the best for use. Second will be aluminum, and I don't see how cardboard only can have any effect!

I choose brass on top of CPU because of the weigh and because I like the sound of brass. The idea was to absorb the micro-vibrations from CPU. I like it very much, it gives more weight and better separation to the sound.

Please note that I'm not any kind of expert in this field. Like I said, I got my ideas from reading a lot of other treads and then put two and two together and try.

Cheers,
Adam

great stuff
you then have the copper bringing emi/rfi to gnd and the 3m sheet will bring further absorption

i wonder if cast iron would sound different to brass, think i have some in the shed and i will try it

[nige2000]

No idea where to go to get brass but I have the neck alright.
Did you get it machined Adam and drilled?

I think I will have to reluctantly put aside my lack of faith in the 3m stuff and maybe try some sheets.

Is that also a machined aluminium enclosure for the SSD or a bought unit?

I kinda shudder to think what any supplier over here would charge for any of this once off stuff.

i might be interested in another sheet of 3m 5100s

think pang was doing hdd enclosures like that

[tony]

Hold your horses I just expressed a possible interest in de paper! Where is the link to the cheap shop selling the stuff for a tenner a sheet? I checked jplay and got lost in the item audio thread that seemed to disappear in smoke.

What are you shielding the usb cable with?

[jkeny]

Something of interest on CA - check out the thread "Why a linear Power Supply"
Looks like John Swenson has teamed up with Superdad (real name?) for some commercial offerings in the computer audio field.
Could be very interesting as JS is quiet an accomplished EE who also is open to thinking outside the box.

Another very interesting thread on CA is about Ethernet cables & the difference it makes to sonics.
Some great posts on the subject from Kurt of BlueJean cables who seems knowledgeable.
Surprising how many Cat cables don't meet spec!
He has interesting things to say with lots of detail - something that has been discovered in our own tweaking - the disconnection of one end of the cable shield connection.

Have you the socket/screen disconnected on the cuinas i cant tell difference either way

Yes, I've been doing that from day one with all my devices, not just the Ciunas - early on I recognised that it was a source of ground-loop, common mode noise.

Shorter cables (of the same type) seem to sound better(more dynamic, detailed, punchy and live sounding

Yes, I believe this may have something to do with less attenuation of the very high frequencies of the square wave & also maybe less chance of reflections in the cable.

screened is much better than not screened

Do you mean screened short cable (connected at both ends) is better than cable without any screen or better than screened cable connected at only one end?

still getting ignored over there
they probably think im taking the piss

They don't realise that we have gone a bit further than they have - maybe you could expand a bit on your post & say how splitting the power supply into independent PSes feeding critical parts of the PC provided the "real magic".

I think that thread is too focussed on the Swenson & Superdad product - maybe enamoured by the names (I found out Superdad is Alex Crepsci - founder of Hovland which is now dissolved).

I doubt that single product will solve all the issues of computer PSes although it seems to be a good first step. The use of a Kelvin Sense ensures the PS delivers a stable voltage - maybe that's concurs with what we found when reverting to batteries with high output capacity - a more stable voltage source? It might be that using a number of these Kelvin Sense voltage sources to supply individual, standalone PS to parts of the computer will be equivalent to what we are doing but at what cost?

[jkeny]

One thing to consider in grounding of emi/rf noise is just how the grounds are dealt with. The intention of this grounding is to re-route this noise away from sensitive signal-carrying areas. It's surprising how many devices treat the ground plane as an infinite sink for noise & share the ground plane (with power & signal) - in other words there is only one ground dealing with the much higher return currents from power & the lesser return currents from signal. This sharing of grounds can result in the power ground return currents polluting the signal ground - the exact opposite of what we want to achieve.
I know that in a PC there is not a lot we can do about it's design, even if we could identify the sensitive signal areas - it's just something to bear in mind

[jkeny]

Nige, I see you posting about your power supplies on Jplay. Why not copy & paste some of those posts to the CA thread & also link to them?
Thinking about the separation of power supplies, what might also be at the root of the success of this approach is what I referred to above - the separate return channels for power ground currents causing less pollution to other grounds?
So we have a two-fold effect - separation of grounds & more stable voltage delivery with high capacity batteries!

[sima66]

No idea where to go to get brass but I have the neck alright.
Did you get it machined Adam and drilled?

I think I will have to reluctantly put aside my lack of faith in the 3m stuff and maybe try some sheets.

Is that also a machined aluminium enclosure for the SSD or a bought unit?

I kinda shudder to think what any supplier over here would charge for any of this once off stuff.

Brass you can find in any metal store. The piece that I used is 2"x 2" x1". Since the CPU has the bolts on the corners, I just drilled a bit each corner, so it sits perfectly flat. The top that is in the picture, is the actual bottom. I will send you a picture.

The SSD enclosure it's very simple. Just a couple of holes and tap. I will send you a couple of pictures, so you can get a better idea.

For everything that I did I used either stainless steel or brass bolts and nuts. I'm trying to avoid magnetic stuff.

[nige2000]

damn just got punished for writing a long post
lost it
will be back later when i regain the will

[nige2000]

More of Adams photos






SSD enclosure with 3M all around

Adam this micro vibration must be a big enough?
do the weights have that much effect?

surprised it had much effect on the SSD, as theres no moving parts (suppose neither does the cpu)
spinning drives are an entirely different matter

think ill look for cast cast iron for cpu later

[nige2000]

Hold your horses I just expressed a possible interest in de paper! Where is the link to the cheap shop selling the stuff for a tenner a sheet? I checked jplay and got lost in the item audio thread that seemed to disappear in smoke.

What are you shielding the usb cable with?

No cheap sources of 3m i pulled the plug on the group buy coz too much hassle and delay (i can be quite impatient)
Mouser is where i got 2 sheets and you could call it €50 per sheet

one sheet is definitely worth it, but by no means any way near the top of the list

Im sheilding with copper tape/foil or copper braid
Made this one up yesterday
its good (2nd best) but not the best i think its because its twice as long as my others
i have it in an envelope here to send up to you for testing