X-bosoz vs. CCS X-bosoz, how does the sound compare?

[protos]

I am still looking for a way to trim absolute dc offset in the x or simple bosoz.This can be quite high when the inter-source resistor is removed.Nelson mentioned trimming r113 /114 but didn't mention what effect this is meant to achieve.Is this important for the simple bosoz as well?

[Henrik]

Originally posted by Nelson Pass
I would add some output resistance to this circuit, as I have
occasionally seen some parasitic oscillations with odd loading
on this and similar circuits. I usually use about 221 ohms (I
have a lot of them).

In my CDP I have some outputresistors at 220 Ohm. I don't have them in my X-BSOZ because it has to drive my version of the X-SOZ which have a verry low inputimpedance, they would take too much gain out. But When driving any thing else they should be in.

Originally posted by Nelson Pass
Also, be prepared to trim the values of R113 and R114 depending on the match quality.

Nelson, I think you have overlooked the fact, that I have placed a DC-blocking capacitor in the feedbackloop. As I see it, you woun't get any biasadjustment trimming R113 and R114 in my circiut. I must admit, that I didn't see this possibility when I decided where to put the cap, at the input or in the feedback. I have just read your SOX paper, an I can se you have chosen to put the cap at the input so you can make the biasadjustment, clever solution indeed. I wish I have done that, I have had a hard time to make the match. Your description of the SOX and the circiut is as useually verry educational stuf -
Thanks a lot.

Protos
I can't see that you shoud be able to trim the offset in the original bsoz (BZLS) by altering the resistors to ground.

Regards

[Henrik]

BTW
If you use a input cap (like in the SOX) in the x-bsoz you also need an outputcap, so may be the sound will suffer a little, but not in SOX.

[Nelson Pass]

Originally posted by Henrik
Nelson, I think you have overlooked the fact, that I have placed a DC-blocking capacitor in the feedbackloop.

I think you're mostly right. That why I said be prepared.

[Alain Dupont]

Hi to all,

The first channel of my CCS-X-BOSOZ is playing Rackmaninoff,
it's pure honney....

Power supply 57 volts from the A75 spare supply {used a 12 volts zener}
and 12 volts for the CCS {LM317}
Cheap transfo's from Active they are 2*28volts Hammond 56 VA
and 2*12volts 12 VA Hammond too.
After a few modifs on the CCS it's running, Nothing more to say
the pot is cheap 10K from Radio Shack, to be replaced by Electroswitch
I have ordered the resistors for 2 Stereo 10K switch Ladder type
{Thanks Nelson} {Modified 2 with 4 sets of contacts}

What a zen result...

I start building the final two channel CCS-X-BOSOZ,

Thanks Nelson and all the group for a so beautifull design!

Have a good night.

Alain.