broken voices........

noticed a breakdown in vocals the other week , particularty female vocals. put this down to being a NOS DAC issue but it seemed to clear.

Last night, infront of the telly with SWMBO we were listening to Fame Academy via the VCR / Audiolab and there it was again - what i can only describe as 'grain'

any ides what the issue is - full system is PDS904 CDP - Derrek Shek NOS DAC - Audiolab 8000A - Quad 12Ls

 

Bring it on thursday and we'll check it out.

 

Only thing in common then is the audiolab and Quads so is a problem with one of them or you could have a loose wire. Check all wiring first, if you still experience it my guess its the amp (getting on a bit now) probably the pot which shouldn't cost too much to repair.
If the cables don't sort it can you borrow an amp from a friend which will tell u if its the speakers or apm

 

cheers guys - i am tending to think its the amp, old i know but little used, but it is left powered up 24/7 if thats going to make a difference.


99.9% sure both channels are afflicted with the problem. will try and run a couple of checks and report / discuss on thurs night - dont think i'll have time to srtrip the amp out to bring it on the night

 

Well, bring it over here any time you like.

 

Earwax...no seriously, earwax

 

No. Earwax doesn't cause grain. All sorts of other problems possibly, but definitely not grain (speaking from several decades of personal experience)

 

You MIGHT have an earthing issue; I used to have an 8000A (my mate's still got it on permanent loan and it still sounds excellent); I had a prologic processor connected to VCR-in, and then ran another set of interconnects to the tape-in on the processor so I could have weird surround sound effects on music (for a giggle). Well, I kept getting "scratchy" vocals and "sandpapery" guitars etc, and it turned out I had some kind of DC offset on the preamp which was causing it. Removal of that other cable solved it...

I'm wandering if your VCR connection is causing an earth loop? They don't always cause hum, but they can really sh*g the sound...

Alternatively, it could just be Lame Academy having shoddy sound quality...

 

Fraid its not just lame Acamedy sound quality - i originally noticed the issuse a couple of weeks ago on CD playback.

System fired up again last night under same conditions - Lame Academy vie VCR playback and no 'grain'. Either its me (earwax - mmm......) ot i have an intermitent equipment issue so i'll keep an ear on it. cheers guys.

 

This seems to summarise my CD listening experience over the last 3 years or so. Same kit, same CDs, Sometimes enjoyable, often painful. Unable to identify the change - and no, it's not level of alcohol.

Mains filtering brought a lot of harshness under control, but not yet where I want/expect the sound to be. And there still seem to be random variations in the sound which is produced.

 

also do you have anything on the tape loop?

maybe a tape out going to something... i had a tape out going to the input of my TV once and because it wasnt a whole loop the amp started making a break up distortion through the midband. unplugged TV and all was well.

 

I read the other nos dac posts....could be an issue there ? How about the Audiolab ? I always found them hard to get on with , speakers are great fab sound. Hows the Nos connected to the cdp? could be a simple cable issue ? Oh and whats powering the NOS?

 

i have just checked my walwart power supply.

it is a mtec model mad-1201 and the spec's are:input=220v 50hz output=dc12v 300mA.

i thought the uk was 240v,could this be a problem? (sorry if this is a dumb question)

kane

 

it's not the problem

 

Kane, presuming you are using the Derek Shek NOS it appears you have rhe same wall wart as he supplied me - take it you have no issues though?

it will be interesting to see how he replies - just advised him today that i have the M-Tec, cant see how it affects things - though improved PSU's do apparently offer a lot to the NOS.

hard to figure this one - presumably there would have been a lot of talk on here, and particularly elsewhere, if there were other NOS's out there with similar issues.
whatever happens with Derek it will be at least a week before anything reaches here from the far east .

 

Chris - if you want to bring it over I'll take a look and see if I can figure out what's going on (without opening it!).

 

Isacc - cheers i think i'll do that - Derek is suggesting i send him a picture of the internals so he can check it out which i can't do - dont have the necessary camera etc and its pointless me taking the lid off cos i aint got a clue what i'm looking at! failing that i get to send it back......
dont mind if you open it, i'll just confiscate your soldering iron beforehand!

 

chris,i do have a derek shek dac and i have a slight issue with female vocals
like katie melua and norah jones-it's very hard to describe the problem but on
the high notes there voices go "gravelly/distored".
i have also noticed it on chris martins voice on "parachutes".

it might be just poor recordings or a high frequency limitation of the dac?

am still happy with the dac but it would be nice to know one way or the other

cheers kane