Rotel RCD 855

[tonitze]

I came across this this Rotel RCD 855 at the used and sell section. I wonder anybody has the info on what chips this player has. Hopefully it has the Tda1541a-S1 with the crown.

[Dr.H]

Transport: TDA8808, TDA8809

then SAA7210, SAA7220

DAC is TDA1541A, no crown. Good machine!

[Shaun]

NT

[ashok]

The crown is printed on the chip and it is a selected chip. I think it has better linearity at low levels than the ordinary one.

Not to worry. The 855 is a great sounding machine IF you modify it. My machine plays even CD-R with no problems at all. mechanically it is very stable and I think reliable. The mechanism must be a Philips one as my vintage Philips CD850MkII has the same transport.My machine was bought in '92.

I have bypassed the analog stage and use a passive LC filter with a tube amp. It also sounds very good with the AD826 and OP2134 ( in order of preference). Much better than the stock machine. With the modifications it is better than the Marantz CD63 II or Cd67 II with upgraded opamps. So go ahead and buy it and tweak it. I am sure with a better power supply and clock it will be even better.

Great machine to play around with.

Dr.H do you by any chance have the circuit diagram for the 855?
I would like to get a copy.

Tonitze,
What URL's do you have for Singapore used and sell audio equipment. How much are you getting this machine for ?
Thanks.

Cheers.

[tonitze]

Ashok,

That player was not found on the net but Local used hifi gear outlet in Singapore. The cost is about $180 Sing. Dollar. You still can try this website for used hifi gear. www.echoloft.com.sg
There is also some link there that you can try.

Thanks everybody.

[tonitze]

Sorry about the URL. It should be www.echoloft.com without the sg

[ashok]

Tonitze,
Thank you for the URL.
I come to Singapore off and on. Can you tell me in which areas I can find shops selling used hi-fi gear. Maybe a shop name if you have it.
Thanks,
Ashok.

[tonitze]

Ashok,

Sim Lim Square- 3rd floor behind near the elevator.
People's Park Complex -3rd floor.Behind next to toilet A lot of old cd player like marantz cd94 etc.

Dickson Road opposite Sim Lim TOWER . A lot of junk but if you're lucky you'll get a good stuff there.

[tonitze]

Anybody had the schematic for this player. I wish to mod it to non-os.

[Dr.H]

Hi

I have modded this machine extensively. See www.audioasylum.com and select tweakers asylum. Search under Ryan or the "TDA1541A chronicles".

Zero-oversampling mod is trivial- Desolder the pins 1, 2 and 3 of the TDA1541, i.e. so that there is nothing connected to these pins. Now connect, either above or below the board, pin 1 of SAA7220 to pin1 of TDA1541, pin2 of 7220 to pin 2 of 1541 and pin3 of 7220 to pin3 of 1541. Zero-oversampling mod done!


Now listen to deeper wider soundstage, clearer more relaxed sound, deeper bass and cleaner highs. I seem to recall the mids having more presence as well. Very worthwhile.
But the Rotel sounds its best when I used rbroers Simple IV converter (search here for it). Really worthwhile to build and simple. Bass becomes very tight and resolved, highs extended (sometimes a bit bright, maybe needs running in) and nice big soundstage.

Other worthwhile mods to 855:
1. Replace rectifiers with fast, soft recovery and bypass with RC snubber (100ohms, 47nF)
2. Bypass low value resistors carrying power supply to chips (typically 1-4 ohms)
3. To get deeper bass, replace the 1uF cap carrying HF to the 7210 with 2.2uF (high quality of course)