Nice! Those are Vishay resistors; very good. The main difference is that OTA uses a resistor for constant current source and SEWA utilizes transistors. Resistors are more linear, but are only half as efficient. How are you planning you PSU?
For the PSU , there will be a common transformator , and then for each channel , a 22 000 µF capacitor , a choke and a 47 000µF capacitor .
Do you think that my heatsinks are appropriated to this project ?
@ + Philippe.
Do you think that my heatsinks are appropriated to this project ?
@ + Philippe.
Hy Mad_K ,
At the end it should look like this :
I had to wind up some more whorls on the transformator to get the sufficient voltage .
@ + Philippe.
At the end it should look like this :
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
I had to wind up some more whorls on the transformator to get the sufficient voltage .
@ + Philippe.
Hy Mad_K ,
I just have one more question !
Is it usefull to put a current limiting circuit between the AC switch and the transformer ?
Best wishes
@ + Philippe.
I just have one more question !
Is it usefull to put a current limiting circuit between the AC switch and the transformer ?
Best wishes
@ + Philippe.
rhr9 said:
Depends on how much power you intend to dissipate. How much power and what is the C/W rating of your sinks?
Hy Mad_K ,
I don' t know the C/W rating of my sinks ... Each IRF 150 is driven by 2.5 A and VCC is 40 VDC : there will be a lot of dissipation but I guess the sink will be right at its place .
@ + Philippe.
I don' t know the C/W rating of my sinks ... Each IRF 150 is driven by 2.5 A and VCC is 40 VDC : there will be a lot of dissipation but I guess the sink will be right at its place .
@ + Philippe.
Here we go ,
At least it is built and it sounds quite well .
I will finalize the case later in order to hide the screws .
According to my Fostex FE208 Back horns it is really enjoyable
to listen to music .
Thanks a lot Mad_K to have making me discover this One Transistor Amplifier .
@ + Philippe.
At least it is built and it sounds quite well .
I will finalize the case later in order to hide the screws .
An externally hosted image should be here but it was not working when we last tested it.
According to my Fostex FE208 Back horns it is really enjoyable
to listen to music .
An externally hosted image should be here but it was not working when we last tested it.
Thanks a lot Mad_K to have making me discover this One Transistor Amplifier .
@ + Philippe.
hy Mad_K ,
Thanks for your appreciation !
Now , what could an improvement from this OTA to a SEWA bring to me ? Will it sound different ?
I enjoy the softness of this model .
Which SEWA schema would be appropriated to my amp ?
Best regards ,
@ + Philippe.
Thanks for your appreciation !
Now , what could an improvement from this OTA to a SEWA bring to me ? Will it sound different ?
I enjoy the softness of this model .
Which SEWA schema would be appropriated to my amp ?
Best regards ,
@ + Philippe.
rhr9 said:
I sounds a little different, but mainly SEWA gives you more power. I wouldn't do anything to that amp
I'm planning to build this amp but I have one question,I need a pre-amp for this amp.Is there anyone who knows a good pre-amp that I could use.I want to build it hard-wired if possible?
If you read the SEWA and OTA threads, this is one of the key elements of these amplifiers, as they are unity gain and needs the preamp to come up with the required voltage swing and a reasonably low output impedance. BOZ is a very good choice. It can easily be hardwired, use a veroboard with soldereyes. Anyways, somewhere in the SEWA thread I propose a slightly modified BOZ with pcb plans etc. Happy hunting 😉
Hi Meanman1964!
I can suggest you the BOZ with Mads PCB and with 2SK216 instead of the IRF610! Very good preamp.
But if you want much more better: build the Mu follower Tube Preamp for SEWA! Designed by Geeks. It will rock you!!!!!😀
Greets:
Tyimo
I can suggest you the BOZ with Mads PCB and with 2SK216 instead of the IRF610! Very good preamp.
But if you want much more better: build the Mu follower Tube Preamp for SEWA! Designed by Geeks. It will rock you!!!!!😀
Greets:
Tyimo
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