Thanks Russellc,
Yes the only desire for the kit was the great enclosure.
So next question is concerning what the output impedance is for the B1 Buffer and how well it will mate with a tube Amp with an input impedance of 100K. Second question is concerning the 25K Linear pot what can be gained by using a different value and are there any solutions for remote control of the pots?
Yes the only desire for the kit was the great enclosure.
So next question is concerning what the output impedance is for the B1 Buffer and how well it will mate with a tube Amp with an input impedance of 100K. Second question is concerning the 25K Linear pot what can be gained by using a different value and are there any solutions for remote control of the pots?
The first post of this thread tells you everything you need for a basic build:
Nelson Pass B-1 preamp kit
You'll also need to buy RCA jacks and hookup wire. If you wish to spend more money and make a "premium" version, then there are many options for the caps / resistors. However, you can probably make a basic version for less than $150.
Regarding 1: Some folks have a preference for the independent control of each channel. Also, some worry about drift between the channels on a stereo pot (although that is usually only a problem at the lower volume settings). There is certainly no problem with using a two-gang pot.
Regarding 2: Since there is no gain on the B1 (it is just a buffer), the initial rotation would do very little (the speaker output would range from very quiet to quiet). By using a linear pot, the initial rotation would bring you into the "usable range" more quickly. Some prefer adjustments in the 9-12 o'clock range.
-Tom
transformer help
Hello guys i am gathering parts for my b1 build and i found a transformer that reads bolulder tech plug in class 2 trans- input 120v 60hz 25w-output 18vdc 533ma will this work as i have read 18vdc seems to work, and is there a way i can test it to see if it puts out 18vdc .
Hello guys i am gathering parts for my b1 build and i found a transformer that reads bolulder tech plug in class 2 trans- input 120v 60hz 25w-output 18vdc 533ma will this work as i have read 18vdc seems to work, and is there a way i can test it to see if it puts out 18vdc .
Very good use of the box
Where did you get those knobs, I've never seen a profile like that but really like them?
Very good use of the box
Papa. From Burning Amp #1.
They are Threshold knobs: (maybe from this?)
Vintage Rare Threshold Model SL10 PreAmplifier for sale - New and Used - PC Game Cheats Codes | PC Cheats Codes
I have a stereo volume pot on the left and the DPDT is actually the knob on the right. Left of center is input one, Center is Off, and Right is input 2.
I only had about .25" around the board on all sides so it's kinda like 10 lbs of stuff in a 5 pound bag in there with the Nichicon KG PS caps folded over the top of everything.
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Well I got the wall wart in and hooked up the B1. No left channel! Took it back out to the garage and found the left wire had come off of the RCA. Fixed.
First up were Robert Plant and Alison Krauss “Raising Sand”. On this album I noticed the vocals had even more separation than before, also the instruments were more defined. Next up was Willie Nelson. This also sounds very clear and all vocals and instruments were available to listen to separately or “all together” if that makes sense. I suck at describing what I hear so I apologize about that.
What I found interesting is that I could tell a difference in the material, not an absolutely huge difference but a change for the better none the less, but my mother in law yelled out to me while listening to the WN album and asked why I turned it down. I called her out to show her the B1 and she commented on how she was able to listen to every instrument in the band and the vocals and thought it was fantastic.
The one bad thing about the way I made mine is that the sound from the right speaker gets to my listening position before the left due to the way the speakers sit in the room. With the B1 (as I have it) I cannot control this since I am using a single pot. This was something I did not think of before going this route, so I guess I will just have to change the area I sit in while jamming.
All in all very happy.
First up were Robert Plant and Alison Krauss “Raising Sand”. On this album I noticed the vocals had even more separation than before, also the instruments were more defined. Next up was Willie Nelson. This also sounds very clear and all vocals and instruments were available to listen to separately or “all together” if that makes sense. I suck at describing what I hear so I apologize about that.
What I found interesting is that I could tell a difference in the material, not an absolutely huge difference but a change for the better none the less, but my mother in law yelled out to me while listening to the WN album and asked why I turned it down. I called her out to show her the B1 and she commented on how she was able to listen to every instrument in the band and the vocals and thought it was fantastic.
The one bad thing about the way I made mine is that the sound from the right speaker gets to my listening position before the left due to the way the speakers sit in the room. With the B1 (as I have it) I cannot control this since I am using a single pot. This was something I did not think of before going this route, so I guess I will just have to change the area I sit in while jamming.
All in all very happy.
You can likely change your speaker positions to be better balanced in all areas, unless the dispersion characteristics prevent this from working...
Here is a picture of the final outcome. I like the small foot print of it now but once that last hermit crab on the other shelf goes to see Davey Jones than I will make a better housing.
I also forgot to say thanks to Pass Labs for making this available and to all those who helped me get a finished B1!
James
I also forgot to say thanks to Pass Labs for making this available and to all those who helped me get a finished B1!
An externally hosted image should be here but it was not working when we last tested it.
James
Andrew,
Thanks for the reply. This was my first venture in something like this and I am still cracking up that a little piece of gear, with what I believe is a small component count can sound so good.
My next project up at some time is going to be the Pearl 2. I all ready have the boards and jfets from Pass ready to go. With that one I do want to make a much nicer looking housing though.
James
Thanks for the reply. This was my first venture in something like this and I am still cracking up that a little piece of gear, with what I believe is a small component count can sound so good.
My next project up at some time is going to be the Pearl 2. I all ready have the boards and jfets from Pass ready to go. With that one I do want to make a much nicer looking housing though.
James
I all, I think my first post. I read the whole thread and built the buffer. My first real build since putting together a couple of Hafler kits in the '80s. I'd been using a P1.0 clone and this B1 is amazing. I'm a tad short on volume with a few cds but I think I can live with it because the sound is so transparent.
Thanks to everyone who contributed and a special thanks to Nelson!
Here are a few pics.
Thanks to everyone who contributed and a special thanks to Nelson!
Here are a few pics.
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