Have you considered sending a private message to someone who has built the B1R2? I found that diyAudio members are always willing to help and to answer questions.
Thanks for the PCB offer, but I don't have a need for it. I'm not even using my B1 anymore, because I built the excellent AKSA Lender preamp.
If you already have a B1R2 or B1 (I don't know what you mean by "blue board"), a rework may not be practical. If you don’t have one yet and want to integrate the Melbourne boards into a new build, why bother? Just build the AKSA Lender preamp.
As with most/all of his designs, Nelson Pass’ B1 is pretty amazing. Fact. But the AKSA Lender is amazinger. I’m pretty sure Mr Pass won’t be offended. New designs are announced regularly on diyAudio and most sound better then the older designs. That’s life. Embrace it.
More advantages of the AKSA Lender preamp:
- You can build it with the amount of gain that suits your system. Being a buffer, the B1 has no gain.
- It doesn’t use any unobtanium components, but I presume you already know that, hence the Melbourne question.
Output Resistance
Hi, I'm thinking about the effect of R104-204 being 1kohm as a output resistance:
if you do the math, considering a load of 47k (F6 amp), the low frequencies cut would be about 0.409Hz. If one use 100ohm (as many suggested) the change would be minimal. 0.400Hz. So, what's the point in reducing it?
Hi, I'm thinking about the effect of R104-204 being 1kohm as a output resistance:
if you do the math, considering a load of 47k (F6 amp), the low frequencies cut would be about 0.409Hz. If one use 100ohm (as many suggested) the change would be minimal. 0.400Hz. So, what's the point in reducing it?
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Hi,
I have a 50k relay resistor attenuator for volume control which has 1024 steps a b1 buffer after it, the b1 has W and CW jumpered, which means it's outputting full volume, due to this I can't use my volume control past 100 of the 1024 steps.
Is there a way to make the b1 show half the volume, maybe a resistor?
I have a 50k relay resistor attenuator for volume control which has 1024 steps a b1 buffer after it, the b1 has W and CW jumpered, which means it's outputting full volume, due to this I can't use my volume control past 100 of the 1024 steps.
Is there a way to make the b1 show half the volume, maybe a resistor?
Attachments
Here is a bit of a heads up to owners of the B1 buffer. It sounds even better if paired with the H2 V1.
I built a B1 (pics in post #4331) and used it for quite some time, but eventually replaced it with another preamp with some gain - to get more volume from my 6W ACA.
After I built an H2 V1, which was generously donated by Papa Pass, I dusted off the B1 and connected it up to the H2 and ACA. This is the best my system has ever sounded. And the amount of gain the H2 has, is perfect for use with the ACA. With the H2 distortion set to 1.1%, the soundstage improved slightly with better layering, but what I like most is the almost mystical way the sound is now reproduced. It just sounds RIGHT to me. Sure, one can argue that the B1 is virtually transparent in sound, but the H2 makes it sound so much better. Now my B1 is being used again and I think that the combination of B1 + H2 will by in my system for a very long time.
I built a B1 (pics in post #4331) and used it for quite some time, but eventually replaced it with another preamp with some gain - to get more volume from my 6W ACA.
After I built an H2 V1, which was generously donated by Papa Pass, I dusted off the B1 and connected it up to the H2 and ACA. This is the best my system has ever sounded. And the amount of gain the H2 has, is perfect for use with the ACA. With the H2 distortion set to 1.1%, the soundstage improved slightly with better layering, but what I like most is the almost mystical way the sound is now reproduced. It just sounds RIGHT to me. Sure, one can argue that the B1 is virtually transparent in sound, but the H2 makes it sound so much better. Now my B1 is being used again and I think that the combination of B1 + H2 will by in my system for a very long time.
About to build the B1, gathering misc parts now.
Question - how difficult would it be to add multiple speaker outputs (via front panel switch) so when going from speakers to headphones the signal to the other output is cut? I was thinking I'd just wire the switch between two sets of line outs but am not sure if there will be some sort of noise when the switch is flipped.
I'm not an experienced builder, so any help is appreciated...
Question - how difficult would it be to add multiple speaker outputs (via front panel switch) so when going from speakers to headphones the signal to the other output is cut? I was thinking I'd just wire the switch between two sets of line outs but am not sure if there will be some sort of noise when the switch is flipped.
I'm not an experienced builder, so any help is appreciated...
I have something similar to that. I added a DP3T switch to the outputs on my B1 (original one with boards provided by Mr. Pass) so that I could switch it to feed three different amps (Fisher 400, Pioneer SX-1250, Pass DIY F6). Works perfectly!