Output Caps
Since my Amp already has a Input cap (4.7uf) do I you really need C101,102 if the only function of C101 & C201 is to form a high pass output filter and block DC passing to the next stage ? Any other reason to keep them in the circuit if your amp is ac coupled this for the standard b1 build.
Since my Amp already has a Input cap (4.7uf) do I you really need C101,102 if the only function of C101 & C201 is to form a high pass output filter and block DC passing to the next stage ? Any other reason to keep them in the circuit if your amp is ac coupled this for the standard b1 build.
Where DC exists or can develop during a fault condition and it is required that that DC voltage be blocked from passing to the next stage, then one needs only 1 DC blocker at that link.
The DC blocker can be located at the output of the source equipment
or
at the input to the receiving stage.
One does not need to block the DC twice.
The user needs reassurance that when he/she connects A to B that there is no to little risk of damage.
the easy way for manufacturers is to always fit a DC blocker at the output of all their equipment and for those same manufacturers always to fit a DC blocker at the input of their equipment.
If you the builder decides to take on the design role, then you need to reassure the user/s that you have designed the equipment such that it does not damage it's self.
How do you do that?
I have my solutions.
What are yours?
The DC blocker can be located at the output of the source equipment
or
at the input to the receiving stage.
One does not need to block the DC twice.
The user needs reassurance that when he/she connects A to B that there is no to little risk of damage.
the easy way for manufacturers is to always fit a DC blocker at the output of all their equipment and for those same manufacturers always to fit a DC blocker at the input of their equipment.
If you the builder decides to take on the design role, then you need to reassure the user/s that you have designed the equipment such that it does not damage it's self.
How do you do that?
I have my solutions.
What are yours?
1st. I started another thread and should have used this one. This thread is unreal! So much information!
I'm interested in building a B1 Buffer and using the PCB.
I'd build the buffer and not use the source 1 / 2 select. This would be pretty simple with just 2 jumpers in the PCB to force the PCB to only use the input 1.
The volume piece I'm not sure what I'd do to bypass the volume pot/attenuator.
Each channel on the PCB for the Pot/Attenuator has a "CCW", "W" and "CW" to connect to the Pot/Attenuator. I'm guessing a jumper introduced to this area would pass the signal in full. I want a pure buffer without attenuation.
I appreciate any help!!
I'm interested in building a B1 Buffer and using the PCB.
I'd build the buffer and not use the source 1 / 2 select. This would be pretty simple with just 2 jumpers in the PCB to force the PCB to only use the input 1.
The volume piece I'm not sure what I'd do to bypass the volume pot/attenuator.
Each channel on the PCB for the Pot/Attenuator has a "CCW", "W" and "CW" to connect to the Pot/Attenuator. I'm guessing a jumper introduced to this area would pass the signal in full. I want a pure buffer without attenuation.
I appreciate any help!!
If you look towards the beginning of the builds, a lot of them were like Andrew describes and truthfully its a simply thing to do. Perfboard might be the easiest route to make sure you never get a short but wiring in the air is still easy with this circuit.
Sure,
I'm thinking perfboard. I wonder if I can just buy the JFET s matched from the pass site... I'm thinking of builing something like this 6 channel buffer
http://www.diyaudio.com/forums/pass-labs/124889-b1-buffer-preamp-319.html#post2805571
I'm thinking perfboard. I wonder if I can just buy the JFET s matched from the pass site... I'm thinking of builing something like this 6 channel buffer
http://www.diyaudio.com/forums/pass-labs/124889-b1-buffer-preamp-319.html#post2805571
YES. Just connect CW to W. Leave CCW open circuit.
Alternatively just connect the single INPUT to the W pin.
So, if I was to replace Q101 and Q201 with current limiting diodes, what would be the best choice for current? From the 2SK170 data sheet it looks like these draw about 11mA with 9 volts across them? (they don't have 11ma current limiting diodes, only 10mA or 12mA, which do I choose?)
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