Teac VRDS-10se Analog Stage mods?

[georgehifi]

I think I'm going to end up with this as a transport, the da stage is twin TDA1547's and a small (yeah right) sprinkling of opamps, can anything be done with is, or are the TDA1547 a lost cause, I've never heard much about them. I will post the semiconductor parts list separatly.

I have my own modded MF A3.24 outboard dac (PCM1738e) which blows this intergrated one away at the moment, when both use the 10se as a transport.

Cheers George

 

[georgehifi]

Parts List

Cheers George

 

[protos]

This site has some extensive non-os modding on a vrds 25 .Pretty close to your player.
http://www.geocities.com/teac_vrds_25x/

 

[georgehifi]

Thanks protos, very interesting read, unfortunatly the 10se is very different to the 25x as far as the da and analog stage goes, and its not much help, but I did save it all just in case one day I end up with a 25x.

Cheers George

 

[Cobra2]

VRDS-10 update; replace/upgrade the digital filter. http://www.audiotuning.de/english/index.html?1-3-teac.html
Then add an extra trafo for the analog-part/board. (Use the stock for digital/transport).
Then; op-amps...

Arne K

 

[georgehifi]

Cobra2 hi, I don't like playing around in the digital side of things as I'm not savy with it. I was thinking more about using the unused pins 10 11 22 23 on the TDA1547's (bypassing it's internal opamps) with some other system instead of all those opampamps servo's and mute transistors. Has anyone had any experience with this, and more important are the 1547's worth it? as I've not heard anyone say these are good or bad dac chips.

Cheers George


Oops! just looked at the 10se diagram again they are bypassing the internal opamps by using 10 11 22 23 any other ideas?

 

[georgehifi]

I've come across this using the SOT1 transformers, but all of the diagrams are for one TDA1547 in stereo mode, I have two TDA1547, would anyone know a cofiguration for two of them?

http://digilander.libero.it/paeng/a__tda1547_tweak.htm

Cheers George

 

[protos]

Well having looked a bit at your schematic for the analog stage it seems that there is a lot one can do there.It is different somewhat to the vrds 25 but the general mod principles applied there also should apply here.There are far too many op-amps in the signal chain and the objective is to limit them.I think the last opamp must be a dc servo if I am not mistaken and the transistor at the output may be a muting transistor.
You could upgrade the opamps of course without changing the circuit.There are special vertical adapter boards.You could do away with the muting transistor,etc,etc.
As for the 1547 chip the 1543 and 1541 are all the rage now with non-os so perhaps it is not bad.
An easy upgrade is of course a high quality clock module.Also easy is the power supply.You could easily substitute some good superregulators (i.e.ALW) there.