It's a nice board, but I like his other one even more, the AB-4. It has a TTL error port you can use to trigger a protection circuit, too. My AB-Q blew up. One of the opamps vapourized a pin! I've sent it back to Pavel to figure out what's wrong with it, and he said he would repair it.
Hi,
in the case of a short-circuit in the end tubes, it is good to protect the AB-Q, or other modules, by:
Auto-Bias board on Roy's website? - Page 7
Post No 161
Pavel
audioamp.eu
Last edited:
Automatic dynamic control bias system for push-pull (PP) amplifiers. ...
This appears to be an exact board-layout match of the module Guido Tent sells, including the supply board. I sure hope this is being done in cooperation and isn't a case of someone ripping off everything including the layout.
thanks for taking care, but it is a rip off, and indeed, pride was so limited that even the PCB was exactly copied.
It doesn't look identical to me at all... Yours has resistors where his has caps, for instance...
No doubt inspired by your design though, but not a carbon copy of it either.
For the record, my testing of the AB-Q and AB-4 makes me conclude the AB-4 is a MUCH better design. It can work with high currents that simply destroy the AB-Q.
No doubt inspired by your design though, but not a carbon copy of it either.
For the record, my testing of the AB-Q and AB-4 makes me conclude the AB-4 is a MUCH better design. It can work with high currents that simply destroy the AB-Q.


It doesn't look identical to me at all... Yours has resistors where his has caps, for instance...
No doubt inspired by your design though, but not a carbon copy of it either.
For the record, my testing of the AB-Q and AB-4 makes me conclude the AB-4 is a MUCH better design. It can work with high currents that simply destroy the AB-Q.
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The model you depict is a derivative of my original module. The Tentlabs modules is exactly copied at first instance. It does not take too much understanding to see that I am not going to link to that copy, but you search and will find. All others are derivatives, adapted to certain applications but all based on the same circuitry.
All models are violating copyrights.
best
So you're saying this is a copy of your module?
Just wondering as it looks nothing like your module, but works much better than the AB-Q he allegedly copied from you.

Just wondering as it looks nothing like your module, but works much better than the AB-Q he allegedly copied from you.
So you're saying this is a copy of your module?
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Just wondering as it looks nothing like your module, but works much better than the AB-Q he allegedly copied from you.
I cannot see what is on that board so cannot judge that. But believe me, my module is copied to the finest details.
The model you depict is a derivative of my original module. The Tentlabs modules is exactly copied at first instance. It does not take too much understanding to see that I am not going to link to that copy, but you search and will find. All others are derivatives, adapted to certain applications but all based on the same circuitry.
All models are violating copyrights.
best
We have already dealt with the indignation of TentLabs. It has been shown that our boards are not subject to TentLabs property rights because our boards are not copies of TenLabs. This dispute was resolved by lawyers from both sides.
The principle of tube current regulation is the same. The reference voltage source is completely different. The power supply is different. The layout of components on the module is similar, but not the same. PCB design is original and different from TentLabs boards.
You can see it in the pictures.
Pavel
audioamp.eu
I cannot see what is on that board so cannot judge that. But believe me, my module is copied to the finest details.
Can you please link to the alleged copy? As I'm not seeing anything that agrees with your statement.
Does anyone know if these modules work OK with cathode FB?
AB-Q FB:

Pavel
We have already dealt with the indignation of TentLabs. It has been shown that our boards are not subject to TentLabs property rights because our boards are not copies of TenLabs. This dispute was resolved by lawyers from both sides.
The principle of tube current regulation is the same. The reference voltage source is completely different. The power supply is different. The layout of components on the module is similar, but not the same. PCB design is original and different from TentLabs boards.
You can see it in the pictures.
Pavel
audioamp.eu
The dispute is not resolved by lawyers from both sides. You are infringing the copyright of the circuit that is used to measure the cathode currents. You have no agreement to use that circuit nor do you pay licenses to the copyright holder.
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