Improvements to CD Playback of a Toshiba SD-9500 ?

I keep thinking I should modify my Toshiba DVD player for 2 channel playback (whillst still keeping ability to playback movies of course !)- apparently its got great Upsampling DACs (well I think they are anyway - they are Analog Devices AD1955s -uses all 6 in 2 channel mode) but spoilt by the worst ever op-amps - NE5532 ??

insides look well built to me anyway - the 2 channel just doesn't seem to cut it - due to the op-amps perhaps -I'm not sure ? Its a very stable transport too.





any ideas ?

thanks, Mark.

 

Interesting... looks like a pretty good layout for the analogue output stage.

As an audio op amp the 5532 isn't terrible... it's the industry standard. However, there's plenty better. OPA2604 and AD8066 could be worth a try, or of course National's hot new LM4562.

The op amp section you show there is very nicely locally decoupled with ceramics right on the pins. However, some good low ESR electrolytics on the rails in that area might help stabilise supplies and lower power rail noise at lower frequencies. Suggest Rubycon ZA or ZL (cheaper, not as good as ZA), or panasonic's finest (about as good as ZL, cheaper).

Beyond that, there's all manner of playing you can do, but I've never found DVD players totally convincing in 2 channel (I've not listened hugely extensively to them though). It might be that you can get a better dedicated 2ch CD player for what you spend on modifying the DVD player.

 

I ouldn;t be so quick to dismiss the 5532 at all; they are very quiet, very stable and capable of great results (for example, many bits of Meridian gear is built around them)

The first place I'd look is cleaning-up power supplies, specificlly to the dac(s) and the analogue output stage.

 

Felix, the 5532 aren't bad, especially in the budget gear, but the LM4562 really does kick it.
Beautiful clarity, none that i've heard before with burr brown opamps, and fantastic timing, dynamics and musicality.
Buy with confidence.
Power supply regulation will help no end

 

I use the LM4562, get em cheap fomr NI themselves. Cost me $10 for delivery and I got three

 

I've been working with the LME49710, the single opamp variant, and unfortunately that's exactly what I can't get out of them to my satisfaction. Have parked them for now, I'll come back to the problem some other time.

Anyway - my point was simply that it'll pay dividends to actually tackle the psu rail(s) properly first. Often, opamp substitutions will bring changes and improvements solely through better (or merely diffferent!) PSRR, in effect masking underlying issues.

 

oops - sorry for the delay in answering - thanks very much for all of your replies ... food for thought for sure.

I got the Sony DVP-S7000 out of the loft the other day to compare ...

mmm... trounces the Toshiba - genuinely to my surprise.

the DACs in the S7000 must be pretty good - even though I've heard its better as a transport than using its analogue stages.

Mark.