One-Bottle Preamp
- Thread starter NewYorkDave
- Start date
Help Support GroupDIY Audio Forum:
madriaanse
Well-known member
Hi Nadege,
check your layout links above; I didn't see it there. Seems like anytime you try to click on a link referenced in this thread you get to some random collection of pictures and what not.... cute. :?
M.
check your layout links above; I didn't see it there. Seems like anytime you try to click on a link referenced in this thread you get to some random collection of pictures and what not.... cute. :?
M.
here it is.
I don't know what happened when I copied the link, it's not the first time I have this problem.
I must be a little bit informatic stupid :?
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=3
thanks forthe advices
I don't know what happened when I copied the link, it's not the first time I have this problem.
I must be a little bit informatic stupid :? http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=3
thanks forthe advices
NewYorkDave
Well-known member
I've been thinking about revisiting the ol' One-Bottle and making a couple of improvements. Here's what I'm considering:
15K:600 output transformer, eliminate High-Z output jack and R10.
Change R13 to 4.7K (this results in higher plate voltage and current, nets a couple dB more maximum output).
Change R12 to 22K, which allows C5 to be reduced in value. (10K was too low, really... excessive load on V1B plate at minimum gain setting).
Change C4 to 4.7uF.
Add high-Z input jack.
It all looks good on paper. If I get a chance to try it out on the bench, I'll report back, probably in a new thread.
15K:600 output transformer, eliminate High-Z output jack and R10.
Change R13 to 4.7K (this results in higher plate voltage and current, nets a couple dB more maximum output).
Change R12 to 22K, which allows C5 to be reduced in value. (10K was too low, really... excessive load on V1B plate at minimum gain setting).
Change C4 to 4.7uF.
Add high-Z input jack.
It all looks good on paper. If I get a chance to try it out on the bench, I'll report back, probably in a new thread.
okgb
Well-known member
Dam you Dave ! i just ordered some parts !
i have a mixer that is 5 into 1 with one tube preamp stages
and looking to make direct outs with enough gain to record with
a low cost output tran would be nice .
keep up the good work
i have a mixer that is 5 into 1 with one tube preamp stages
and looking to make direct outs with enough gain to record with
a low cost output tran would be nice .
keep up the good work
pstamler
Well-known member
No reason you can't keep the high-Z output jack; just make it a switching TS jack to take the output transformer out of circuit when the plug's plugged in.
Peace,
Paul
Peace,
Paul
okgb
Well-known member
My mixer [ a groemes ] is , i think typical of the times where each one 12ax7 input stage sums through resisters into another stage then drives a tone stack with a recovery stage and then another one tube to drive the
output xfmr
I had considered your Zen version Paul , but i'm on the fence as to wether i can get away with moddign the channels or if it would be better to
strip the whole thing first !
take care , reagdrs Greg
output xfmr
I had considered your Zen version Paul , but i'm on the fence as to wether i can get away with moddign the channels or if it would be better to
strip the whole thing first !
take care , reagdrs Greg
skipwave
Well-known member
[quote author="pstamler"]No reason you can't keep the high-Z output jack; just make it a switching TS jack to take the output transformer out of circuit when the plug's plugged in.[/quote]
I think Dave was doing away with the option because he plans to remove the tiedown resistor, R10. Although, it seems worth trying unbalanced without it. If this was run direct into a 10k or greater impedance, is that expected to load down the plate of V1B too much, maybe only with the gain pot at min?
I will find time to try these new options soon. I've been meaning to whip together the zero feedback variant for awhile.
I think Dave was doing away with the option because he plans to remove the tiedown resistor, R10. Although, it seems worth trying unbalanced without it. If this was run direct into a 10k or greater impedance, is that expected to load down the plate of V1B too much, maybe only with the gain pot at min?
I will find time to try these new options soon. I've been meaning to whip together the zero feedback variant for awhile.
hello here are some pisture of my "hardrive one bottle"
the unit is not tested yet....
Comments are welcome
http://www.twin-x.com/groupdiy/displayimage.php?album=87&pos=4
http://www.twin-x.com/groupdiy/displayimage.php?album=87&pos=5
http://www.twin-x.com/groupdiy/displayimage.php?album=87&pos=6
http://www.twin-x.com/groupdiy/displayimage.php?album=87&pos=7
enjoy :grin:
the unit is not tested yet....
Comments are welcome
http://www.twin-x.com/groupdiy/displayimage.php?album=87&pos=4
http://www.twin-x.com/groupdiy/displayimage.php?album=87&pos=5
http://www.twin-x.com/groupdiy/displayimage.php?album=87&pos=6
http://www.twin-x.com/groupdiy/displayimage.php?album=87&pos=7
enjoy :grin:
tommypiper
Well-known member
[quote author="NewYorkDave"]I've been thinking about revisiting the ol' One-Bottle and making a couple of improvements. Here's what I'm considering:
15K:600 output transformer, eliminate High-Z output jack and R10.
Change R13 to 4.7K (this results in higher plate voltage and current, nets a couple dB more maximum output).
Change R12 to 22K, which allows C5 to be reduced in value. (10K was too low, really... excessive load on V1B plate at minimum gain setting).
Change C4 to 4.7uF.
Add high-Z input jack.
It all looks good on paper. If I get a chance to try it out on the bench, I'll report back, probably in a new thread.[/quote]
Dave, I'd love to see this. Haven't built one yet, and glad you're still improving it. Please let us know when you have the updated design.
15K:600 output transformer, eliminate High-Z output jack and R10.
Change R13 to 4.7K (this results in higher plate voltage and current, nets a couple dB more maximum output).
Change R12 to 22K, which allows C5 to be reduced in value. (10K was too low, really... excessive load on V1B plate at minimum gain setting).
Change C4 to 4.7uF.
Add high-Z input jack.
It all looks good on paper. If I get a chance to try it out on the bench, I'll report back, probably in a new thread.[/quote]
Dave, I'd love to see this. Haven't built one yet, and glad you're still improving it. Please let us know when you have the updated design.
NewYorkDave
Well-known member
Those are just ideas which should work but haven't been tested yet. I'll let you know if I get around to trying it on the bench.
skipwave
Well-known member
[quote author="Nadege"]hello here are some pisture of my "hardrive one bottle"
[/quote]
It's a MILA, right? Not a One-Bottle?
[/quote]
It's a MILA, right? Not a One-Bottle?
khstudio
Well-known member
[quote author="NewYorkDave"]Those are just ideas which should work but haven't been tested yet. I'll let you know if I get around to trying it on the bench.[/quote]
I'm interested :thumb:
I'm interested :thumb:
skipwave
Well-known member
[quote author="Nadege"]No, it's a one bottle the fille is named MILA but it's just because I'm lazy when importing picture to my computer and I'm giving the same name to all my pictures... :?[/quote]
Your links in this thread are pointing to the MILA pictures. I found your One-Bottle pics by viewing all your uploads. So, the blue case is the MILA and the Lacie case is the One-Bottle.
A couple of things about the One-Bottle, by having the turret board on the bottom of the case, and the tube socket on the lid you've made your wires running to the socket rather long. It would be better to have components mounted on the socket or at least close. Might not be much of an issue in practice. If it's quiet, it's all good.
Also, the Edcor output transformer is not shielded, and you have it mounted on the outside of the case. Again, might not be an issue, but in a room full of interference, RFI, EMI, etc., it might be. If you put it in a rack, you will have to careful how close it is to other cases that have externally-mounted power transformers and such.
Your links in this thread are pointing to the MILA pictures. I found your One-Bottle pics by viewing all your uploads. So, the blue case is the MILA and the Lacie case is the One-Bottle.
A couple of things about the One-Bottle, by having the turret board on the bottom of the case, and the tube socket on the lid you've made your wires running to the socket rather long. It would be better to have components mounted on the socket or at least close. Might not be much of an issue in practice. If it's quiet, it's all good.
Also, the Edcor output transformer is not shielded, and you have it mounted on the outside of the case. Again, might not be an issue, but in a room full of interference, RFI, EMI, etc., it might be. If you put it in a rack, you will have to careful how close it is to other cases that have externally-mounted power transformers and such.
I think I'll never manage to have the link to the rigth picture in my post, I'm always dubble checking them when writing them, but it's always wrong... Here are the rigth link (I hope)
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=3
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=4
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=5
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=6
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=7
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=3
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=4
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=5
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=6
http://www.twin-x.com/groupdiy/displayimage.php?album=60&pos=7
Hi!
I was thinking of substitute for 12AV7. That's because 12AV7s are rare where i live, and by my experience with One Bottle they need to be selected for low noise. I know i could chechk for another design, but this one is very nice because it is simple, don't need output transformer, input is easy to get, preamp sounds good to me, gain is high enough for everything i tired until now.
So what could be the substitute? Someone mentioned ECC99, but data sheet shows it's different from 12AV7. What should be changed in design to use ECC99 or any easy to get tube (maybe from JJ/Tesla)?
I'm sure more people would build this thing if it would be based on tubes in ECCXX familly.
Miha
I was thinking of substitute for 12AV7. That's because 12AV7s are rare where i live, and by my experience with One Bottle they need to be selected for low noise. I know i could chechk for another design, but this one is very nice because it is simple, don't need output transformer, input is easy to get, preamp sounds good to me, gain is high enough for everything i tired until now.
So what could be the substitute? Someone mentioned ECC99, but data sheet shows it's different from 12AV7. What should be changed in design to use ECC99 or any easy to get tube (maybe from JJ/Tesla)?
I'm sure more people would build this thing if it would be based on tubes in ECCXX familly.
Miha
ciminosound
Well-known member
Ciminosound thanks :thumb:
I checked further and found out that 12AT7/ECC81 is very similar to 7062, 5965, 6829 and 6201.
Link is here: http://www.audiotubes.com/12at7.htm
ECC81 is very easy to find here, and we have big stocks of Ex Yugoslavian NOS (EI Nis), and some NOS German too.
Characteristics of ECC81 are similar to 12AV7, but not all.
So, is ECC81 close enough to use it, or i should do some mods to One Bottle?
Miha
I checked further and found out that 12AT7/ECC81 is very similar to 7062, 5965, 6829 and 6201.
Link is here: http://www.audiotubes.com/12at7.htm
ECC81 is very easy to find here, and we have big stocks of Ex Yugoslavian NOS (EI Nis), and some NOS German too.
Characteristics of ECC81 are similar to 12AV7, but not all.
So, is ECC81 close enough to use it, or i should do some mods to One Bottle?
Miha
