mpmarino said:Someone's gonna come around and delete the last 5 or 6 pages
Only Papa could do it. Ok until Papa wakes up I think . . .
Hmm . . . I'd like try JFET BOZ with J310 instead of 2SK...
J310 has lower transconductance than 2SK... and will probably
give higher distortion . . . But, is this a considerable problem?
Reporting in:
I tried and tried, but I couldn't get satisfying sound out of this - I built 2 layouts and protoboarded it, but I think it needs to be adjusted for each specific setting according to the rest of the system.
I did find that the zhaolu 2.5 dac puts out a much larger output than my dvd player
Testing:
Trace layer - there is a trace missing between PSU Cap + that was fixed:
Top layer:
CMOY killer version - next to some 2SK389V and 2SJ109BL:
I haven't given up yet though, just taking a break - I'm planning on building a version with cermets in place of some of the resistors so I can tweak on the fly
I tried and tried, but I couldn't get satisfying sound out of this - I built 2 layouts and protoboarded it, but I think it needs to be adjusted for each specific setting according to the rest of the system.
I did find that the zhaolu 2.5 dac puts out a much larger output than my dvd player
Testing:
Trace layer - there is a trace missing between PSU Cap + that was fixed:
Top layer:
CMOY killer version - next to some 2SK389V and 2SJ109BL:
I haven't given up yet though, just taking a break - I'm planning on building a version with cermets in place of some of the resistors so I can tweak on the fly
Hi there!
I'd like to build a boz and add a tone control to it (i know it's not such an audiophile approach
) but i don't know how to do it.
I'd like something that boost upper and lower leaving midrange frequency untouched. Is it possible to do? Are there schematics avaiable?
Many thanks in advance.
Ciao!
Marco
I'd like to build a boz and add a tone control to it (i know it's not such an audiophile approach
) but i don't know how to do it.I'd like something that boost upper and lower leaving midrange frequency untouched. Is it possible to do? Are there schematics avaiable?
Many thanks in advance.
Ciao!
Marco
Back on topic 
Jfet BOZ deceived me!
When I built it, I was testing it with amps that do have some voltage gain. With F2 lite, Jfet BOZ was working fine, very clean and musical as well.
What happened? I modified F2 into "Ota-one transistor amplifier". For those that didn't read that thread, that's simply a follower-no voltage gain. So I had to push Jfet Boz more...and then it distorted...
I cut one of 27 ohm source resistors. Became a bit cleaner, but not much...Ok, at low volumes it still sounds wonderful, one of the best combinations ever heard (jfet+ota). This made me want more...but Jboz distorts!
So it seems that it is not capable of swinging enough voltage, or maybe I need to experiment more with resistor values. Or, add two batteries more, and make it 36v supply...
Regards,
Vix
Jfet BOZ deceived me!
When I built it, I was testing it with amps that do have some voltage gain. With F2 lite, Jfet BOZ was working fine, very clean and musical as well.
What happened? I modified F2 into "Ota-one transistor amplifier". For those that didn't read that thread, that's simply a follower-no voltage gain. So I had to push Jfet Boz more...and then it distorted...
I cut one of 27 ohm source resistors. Became a bit cleaner, but not much...Ok, at low volumes it still sounds wonderful, one of the best combinations ever heard (jfet+ota). This made me want more...but Jboz distorts!
So it seems that it is not capable of swinging enough voltage, or maybe I need to experiment more with resistor values. Or, add two batteries more, and make it 36v supply...
Regards,
Vix
The circuit has a sweet spot, but outside of that, it won't work
as well. More supply voltage will increase the distortion.
You will need a more complex circuit, or one whose JFET better
fits the characteristic you want. Offhand, I don't have a
suggestion for that part.
Suffice it to say you will need a more complex circuit than that
to do the job.
I guess it's a good time to trot one out...
as well. More supply voltage will increase the distortion.
You will need a more complex circuit, or one whose JFET better
fits the characteristic you want. Offhand, I don't have a
suggestion for that part.
Suffice it to say you will need a more complex circuit than that
to do the job.
I guess it's a good time to trot one out...