After building one B1 and four BoZ I have to agree they are quite different. The B1 has a better mid-range but the bass, though as extended as Boz is not as weighty. Both preamps go from 5hz to over 180khz.Different. The B1 is very neutral. The BOZ is definitely colored in its' sound. I would say the J-BOZ has a bit of a classic tube sound. Personally I like them both, but at the end of the day, they are different. For the money, build one and find out.
BoZ has a heavier lower register, smooth mid-range and highs. I have 3W SET amps so I must use BoZ because I need lots of gain, which it has. I build my BoZ without input caps because my Oppo BDP-83SE has output caps and my Mongrel Dog Audio Pacific phono preamp has output caps. If You don't need input caps don't put them in.
James; I have thought of this but I would go the other way. BoZ front end with B1 back end.
are you both saying the same thing?
where is the volume control in this suggestion?
James said "j-Boz in front"
Mhouston said "BoZ front end"
That to me is the same arrangement.
Are you both saying the same thing?
As an aside, since you are both talking about conditioning the signal before reaching the power amp. It seems sensible to recommend where the volume control should be in that signal conditioning arrangement.
Mhouston said "BoZ front end"
That to me is the same arrangement.
Are you both saying the same thing?
As an aside, since you are both talking about conditioning the signal before reaching the power amp. It seems sensible to recommend where the volume control should be in that signal conditioning arrangement.
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Different. The B1 is very neutral. The BOZ is definitely colored in its' sound. I would say the J-BOZ has a bit of a classic tube sound. Personally I like them both, but at the end of the day, they are different. For the money, build one and find out.
haha different strokes for different folks ey? funny how different people explain sound, these 2 descriptions read to me like 2 totally different amps
That was a silly answer from me.
I would place the attenuator between the two preamps. I'm REALLY not sure if it would be better to BoZ first or last. I have both so it would not be hard for me to inter-connect the 2 and try the two possible combinations.
I think with the B1's ability to buffer and drive it may be better up front. In my B1 there is a 15% loss in signal due to the fact it is a source follower. Keep the gain stage (BoZ) for the back-end. And as I said the attenuator between the two.
I've run mine from 3 X 9V batteries for 27V. Because it only draws 12mA you can get about 50 to 100 hours of play out of lithium non-rechargables.
The other way I powered BoZ is with external plug-pack transformer, diode bridge and some big filter caps. My BoZs have 20,000uf to 30,000uf of filter cap on the board with the rest of the components.
I've never had any hum or noise yet.
The other way I powered BoZ is with external plug-pack transformer, diode bridge and some big filter caps. My BoZs have 20,000uf to 30,000uf of filter cap on the board with the rest of the components.
I've never had any hum or noise yet.
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What I found was the SMPS wall wart worked with the B1 but buzzed with BoZ. I think part of the reason is B1 has negative gain (haha) and better PSRR. BoZ has gain and poor PSRR. There is no need at all to leave these units on 24 X 7. As long as you are using them often, turning them on 20 mins prior to use should be enough.
If you want the schematic to my remote PSs let me know. But remember I have very large caps right on the cct. brd.
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If you want the schematic to my remote PSs let me know. But remember I have very large caps right on the cct. brd.
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That's alright. It's too much trouble. I will just stick with the B1 and enjoy. Thanks.
If you want the schematic to my remote PSs let me know. But remember I have very large caps right on the cct. brd.
******************************************************
That's alright. It's too much trouble. I will just stick with the B1 and enjoy. Thanks.
Hello everyone.So many times when I google some idea I have I'm directed to diyaudio.
Some good ideas floating in here for sure.Love the pictures too.
Well I need a preamp and found out about Nelsons JFET BOZ.
So today I built one.
Put it on one of the small pcbs you get a R.S. the kind that comes two to a package.
I didn't split the two boards and built the left and right side of course as mirror images of each other.
The right side gets 15.5Vdc from the power supply but the left side only shows me 5.5Vdc.
Did I make a voltage divider and not know it?Has something like this happened already to another builder?
Any ideas?I will be back at it again tomorrow to troubleshoot this board.Will look to see if I have everything were it should be.The fact that the right side is good makes me think I have a component in the wrong place or I have a leg from one component were it does not belong.
Also maybe you could answer me this.
What mechanism do I use to tie the two boards together of course for the stereo effect?
I'm using 15.5vdc so how do I get 15vdc to both the left and right side simultaneously?
When I put the signal from my CD player to the board I ran it this way.
Signal in from CD player to B25k linear pot,pin one,to pin two (wiper)out,to the junction of 1k & 1M ohm resistor.Pin 3 of the pot to ground.
Audio out is from 475 ohm resistor to the main amp audio in via RCA.
I get a loud hum which will not vary with the volume up or down and I can hear some music.
Should the RCA in and out both be grounded?
Plus I'm a bit confused about grounding the circuit needless to say.Seems like I either have too many points grounded or not enough and not just on this project.
I have read 40+ pages on this thread but to tell you the truth...going through the next 60+ pages probably will not help me to get this thing running.
Just a few simple answers may put me in the correct direction.Any help you can give me is greatly appreciated.
Thank you Nelson Pass for the design and for publishing it for us to use.
Some good ideas floating in here for sure.Love the pictures too.
Well I need a preamp and found out about Nelsons JFET BOZ.
So today I built one.
Put it on one of the small pcbs you get a R.S. the kind that comes two to a package.
I didn't split the two boards and built the left and right side of course as mirror images of each other.
The right side gets 15.5Vdc from the power supply but the left side only shows me 5.5Vdc.
Did I make a voltage divider and not know it?Has something like this happened already to another builder?
Any ideas?I will be back at it again tomorrow to troubleshoot this board.Will look to see if I have everything were it should be.The fact that the right side is good makes me think I have a component in the wrong place or I have a leg from one component were it does not belong.
Also maybe you could answer me this.
What mechanism do I use to tie the two boards together of course for the stereo effect?
I'm using 15.5vdc so how do I get 15vdc to both the left and right side simultaneously?
When I put the signal from my CD player to the board I ran it this way.
Signal in from CD player to B25k linear pot,pin one,to pin two (wiper)out,to the junction of 1k & 1M ohm resistor.Pin 3 of the pot to ground.
Audio out is from 475 ohm resistor to the main amp audio in via RCA.
I get a loud hum which will not vary with the volume up or down and I can hear some music.
Should the RCA in and out both be grounded?
Plus I'm a bit confused about grounding the circuit needless to say.Seems like I either have too many points grounded or not enough and not just on this project.
I have read 40+ pages on this thread but to tell you the truth...going through the next 60+ pages probably will not help me to get this thing running.
Just a few simple answers may put me in the correct direction.Any help you can give me is greatly appreciated.
Thank you Nelson Pass for the design and for publishing it for us to use.
are we supposed to pick out detail from those?
crop to CB size.
post at 800*600 and use daylight not flash offset to one side.
If you must use flash then get two set up to both sides and aimed at ~ 45degrees to the CB so that we don't see reflections and the CB is fairly evenly lit.
Simpler to use outdoor daylight.
crop to CB size.
post at 800*600 and use daylight not flash offset to one side.
If you must use flash then get two set up to both sides and aimed at ~ 45degrees to the CB so that we don't see reflections and the CB is fairly evenly lit.
Simpler to use outdoor daylight.