TS9/808 mod = TS9DX/808 mod?

[Xavier]

I want to try the 808 mod in my TS9DX, but I haven't found any schematic of it, and I don't know if other than the obviously different clipping section, the rest of the circuit is the same.

Also, what does exactly the 808 mod does? is it a tone mod, or will it affect the impedance as well ?(I'm using SS amps)

[MartyMart]

Hi, I dont have the schematic but I'm pretty sure that apart from those different "hot clipping" modes, its the same.
It depends on which one you have, if its a newer one or even some "Japan made"  '80's ones have a "TA75558P" op-amp, ( YUK! )  this is worth removing/socketing and changing for either an original JRC4558D a TI4558/4559 or an NE5534an/ap or OPA2134pa.
The rest of the "808" mods you find are all worth doing and should result in a better tone/less noise.
If you are using an "SS" amp then dont bother with the output resistor changes, they are meant for use with a valve amp, as in late 70's early 80's models and as you will read its a "subtle" change at best !
Input resistor change from the stock 470k to 620k/680k is worth while too.
Hope thats going to help ?
Regards,
Marty.

[Xavier]

I have already a socketed JRC4558DD. To be honest I can't hear any difference, but the TI sample package is coming , containing both OPA2134's and OPA2604's........

I guess raising the input resistor will raise also the input impedance, I have to try that.

I won't touch the output resistors then, thanks for the advice !!

[MartyMart]

I guess raising the input resistor will raise also the input impedance, I have to try that.

Yes, you'll get better signal even when bypassed ( Robert Keeley touch )
I've changed both small tantalun "tone" caps to metal film, though some prefer the tants, you wont need to do the "more/less" drive mod as you effectively have that in the "DX" anyways :-)

Marty.