yes , you can
but then you must remember for all times that there is some DC on output RCA
if you're making integrated with MoFo , then it's no brainer
though - in case of stand-alone pre , you can make two sets of RCA outputs , visible named as DC coupled and AC coupled
but then you must remember for all times that there is some DC on output RCA
if you're making integrated with MoFo , then it's no brainer
though - in case of stand-alone pre , you can make two sets of RCA outputs , visible named as DC coupled and AC coupled
Wondering about this, can the two outputs, one AC one DC just be wired off the same output pads of boards? One wire set to RCA, one wire set to caps, then on to other RCA? Or should there be something, resistors, etc to isolate them?
Russellc
I have been working to increase the gain of my BA-3 board
At the suggestion of the gentlemen on this thread...
To get more gain out of my BA-3 board, I increased r13 in steps. I saw that gain did go up. Where for one volt rms of input, I was getting 9 volts rms of output...With a higher ohm r13 of around 500 ohms, I could get 18 volts rms of output from one volt rms of input. No clipping observed on my scope at 1 volt input.
However, I could see on my scope that upon raising the input voltage to 1.5 volts or so, the output would clip.
It seemed that I could get more output swing with out clipping by raising the bias of the MOSfets. But I could only do this to a point. I then blew out a mosfet when I was at 3volts dc across the bias resisters.
So is there a way I can get rid of the clipping when input voltage is raised to say 2 volts.
This has been a great and instructive project...Haven't started the MOFO yet.
At the suggestion of the gentlemen on this thread...
To get more gain out of my BA-3 board, I increased r13 in steps. I saw that gain did go up. Where for one volt rms of input, I was getting 9 volts rms of output...With a higher ohm r13 of around 500 ohms, I could get 18 volts rms of output from one volt rms of input. No clipping observed on my scope at 1 volt input.
However, I could see on my scope that upon raising the input voltage to 1.5 volts or so, the output would clip.
It seemed that I could get more output swing with out clipping by raising the bias of the MOSfets. But I could only do this to a point. I then blew out a mosfet when I was at 3volts dc across the bias resisters.
So is there a way I can get rid of the clipping when input voltage is raised to say 2 volts.
This has been a great and instructive project...Haven't started the MOFO yet.
do not use force , use a bigger hammer
increase gain (R13) , not input voltage
2Vrms , when everything is OK, is on the verge of clipping (of everything) , but with 510R for R13 , that's output swing of nearly 70Vpp , if you're using +/-36V rails
so ,make your mind - whatever you need , you need to optimize stage , not forcing it on input
though , connecting 115Vac directly from mains to input could induce some interesting things , even if not for long
increase gain (R13) , not input voltage
2Vrms , when everything is OK, is on the verge of clipping (of everything) , but with 510R for R13 , that's output swing of nearly 70Vpp , if you're using +/-36V rails
so ,make your mind - whatever you need , you need to optimize stage , not forcing it on input
though , connecting 115Vac directly from mains to input could induce some interesting things , even if not for long
Ok
Thanks...I am coming to understand things better...was expecting too much and going over the capacity of the circuit...
Can I operate the BA-3 with 36 volt rails...I thought 32 was max...
Thanks...I am coming to understand things better...was expecting too much and going over the capacity of the circuit...
Can I operate the BA-3 with 36 volt rails...I thought 32 was max...
well , 36V rails , which I mentioned , were more example in context what circuit is capable of with minimal needed adjustments (R13)
32Vdc is certainly on safer side, 36Vdc already looking for Devil
if you're going to use it with MoFo , even 24Vdc rails are enough
32Vdc is certainly on safer side, 36Vdc already looking for Devil
if you're going to use it with MoFo , even 24Vdc rails are enough
Thanks...Zen Mod...For all your help....
Yes...I understood that you were using 36 volts to illustrate a point...
I will stop meddling with the design, and go on to the MOFO...
Yes...I understood that you were using 36 volts to illustrate a point...
I will stop meddling with the design, and go on to the MOFO...
question
Good morning, gentlemen,
In the event that I remove the C 3 condenser ( 10µF), should I leave the R 12 resistance of 100ohms?.
By thanking you in advance.
Toto 34
Good morning, gentlemen,
In the event that I remove the C 3 condenser ( 10µF), should I leave the R 12 resistance of 100ohms?.
By thanking you in advance.
Toto 34
Thanks Zen Mod ,yes I am of a natural cautious ,at this moment I listen to the little Mofo +BOZ=not bad like listening but the Zen 9 is superior,the criticism is very valid because the Boz does not have enough gain and has an impedence can-be too high,Iyearn to achieve the BA-3 fronted .
Choice for a good value of the volume control.
To commend the BA-3 preamp a potentiometer of 20 Kohms is a correct value?
To commend the BA-3 preamp a potentiometer of 20 Kohms is a correct value?
Yes, it should be fine. I was using 25k stepped attenuator with my BA-3.
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