Hiya. Let the madness ensue.

[Shane Hanify]

Gidday all, been lurking these forums for some time and I thought it was time I was a bit more active.

 

I've been in and around Music for decades and just recently got into home theatre. Love tweaking and adore putting bang for buck systems together on a shoestring budget, hence the mishmash components I've listed. (The IC / spk cable list is a mix of DIY / budget interconnects, but not those horrid throwaway ones).

 

The DVD side of things runs through a 17" Philips monitor via a TV tuner card in the PC with the sub / mains handled by the AudigyII ZS soundcard.

 

The CD player is routed through the SPDIF until a standalone DAC is obtained.

 

I do have a TT (80's vintage Technics SL-D303 with a Shure N70BX cart) but being as I haven't bulit a table for it, it's currently not in use.

 

These will be updated as the upgrades occur (slowly).

 

Current / future projects include revamping the Perreaux without losing its character, (it has an annoying hum *only* when the pc is connected. Quiet, but audible at low listening levels), getting a class-A valve amp built, sorting out a headphone amp and a semi-decent set of cans and helping build / buying a sub/sat speakers / amps for the HT system. In no particular order.

 

 

Cheers, Shane.

[conan1553552684]

re hum (from PC)

 

sounds like a hum loop. I had this when connecting a PC sound card output to an AV amp.

 

You could try this:

in the lead connecting the sound from PC to the amp - disconnect earth connection in L and R plugs (at one end only)

[Shane Hanify]

Thanks Conan, but that was one of the first things that was tried. Along with swapping out the psu (of the pc), swapping out the soundcard, trying different locations for the equipment, etc etc etc. All other source equipment is a near silent connect (low floor noise, but that's to be expected).

 

Someone along the line told me that the vintage of the Perreaux's Transformer / power supply could be causing the issue. Will look at swapping out that at some stage, just have to get it all organised.

[conan1553552684]

Yes, transformers can be a source of hum. In theory a shielded box should eliminate it but only seems to work in a vestgial sense.

 

I did the following once and reduced hum some 50%:

 

wrap the transformer coil with an earthed copper band - not too diffcult to do if the windings form a cube - but not for the faint-hearted or inexperienced! Hard work to get the wrap right too.

[Shane Hanify]

I assuming you're talking about a Faraday cage? I looked into the possibilty some time ago, but I think I'll run with upgrading the ps of the Perreaux If I get it right, it should really bring the old girl alive (working on the basis that if I use a high enough current transformer etc then the headroom should dynamically increase).

 

[edit] And I don't want to reduce the hum, I want to eliminate it

[conan1553552684]

Faraday cages - discussed this with a master electrical engineer once. We agreed there well-nigh impossible to get right unless a real expert is involved, and even then ..........

 

Can Perreaux do things like replace PSU from older products ?

SME have this reputation - come back 20 years later and they still have the part !!

[Shane Hanify]

I don't know if Perreaux would replace just the ps, and even then the sheer cost involved would outweigh what I paid for the amp by a large margin. The old girl's had a hard life and needs a major overhaul, something I'm capable of undertaking myself - sort of a sympathetic restoration if you will. I just don't want to lose that trademark sound, just want to get the old girl to breathe a bit more easily.