With BA-3 which is a kind of "power buffer" you need lots of gain... B1 buffer, B1 Nutube have no gain. So it won't work. IronPre has 6 or 12dB it won't be enough (12dB could be enough if you have HR speaker).
BA-3 pre is a perfect match.
I will use IronPre 6dB version to drive the "complete" BA-3 (meaning BA3 FE and complementary output PCB). If I have too much gain, I will decrease it changing resistor value on BA3-FE.
I just hope they gonna match together... After that I will try a classe B power amp by Plantefevedriven by the IronPre
Damien
I've tried BA3 with Iron Pre, very nice pairing. Right now I am impressed with a BA3 with Burning Amp 2018 line stage.
I have also used BA3 amp with BA3 front end works fine. Even with Pearl 2 in the mix that is pretty "gainfull" itself. Just less twist on volume knob.
Russellc
I see. Looking at Waynes Linestage in the threads. A few new challenges for me if going that route, SMD being one of them. How do you experience the gain level a match for the BA-3? Dont want to waste good signal, but of course, it is possible to adjust the gain resistor- or transistorwise.
Also, a challenge is there is no build thread for Waynes Linestage, though 6L6 har posted his build i the Wayne thread. What chassis from the store is a good fit? And go regulated or not?
A BOM would be very very nice. Not for the parts on the board, but for everything else: volume knob, selector, etc.
And how do you guys drill holes for RCA’s and volume knobs and such? I have a messed up backplate (not my doing) that I am going to replace. I want it looking good, or anyways my wife does, and a lot of times, that counts a lot.
Also, a challenge is there is no build thread for Waynes Linestage, though 6L6 har posted his build i the Wayne thread. What chassis from the store is a good fit? And go regulated or not?
A BOM would be very very nice. Not for the parts on the board, but for everything else: volume knob, selector, etc.
And how do you guys drill holes for RCA’s and volume knobs and such? I have a messed up backplate (not my doing) that I am going to replace. I want it looking good, or anyways my wife does, and a lot of times, that counts a lot.
The gain is fine on the line stage. BA3 has the same OS as the F4, but unlike the no gain front end on F4, BA3 has lots of gain compared to my other First Watt clones.
I like gain in a preamp, so my B1 isn't my go to as a rule. When used with Pearl 2 and BA3, I have plenty of gain in my vinyl system, speakers are about 86 dB. Otherwise I like a pre with gain.
As to the smd parts, I had never done it before either. No biggie. Put a thin touch of solder to the pads. Place fet on thin piece of scotch tape, touch one pad with tip of iron sticking it. Then do other pads. When done, go back to first pad and touch up. Make sure to carefully clean newly soldered fet and board with alcohol and tooth brush.
I like gain in a preamp, so my B1 isn't my go to as a rule. When used with Pearl 2 and BA3, I have plenty of gain in my vinyl system, speakers are about 86 dB. Otherwise I like a pre with gain.
As to the smd parts, I had never done it before either. No biggie. Put a thin touch of solder to the pads. Place fet on thin piece of scotch tape, touch one pad with tip of iron sticking it. Then do other pads. When done, go back to first pad and touch up. Make sure to carefully clean newly soldered fet and board with alcohol and tooth brush.
Well, what can I say? That settled it. Just ordered the Wayne LS board, and regulator boards, from the store. Any experiences with the regulators, and / or tips I should have before I start? I have yime to plan ahead, as the power amp ain’t finished yet. Probably will take a while. Baby steps
to andynor #365
Hello andynor,
I have built 2 versions of the BA-3 poweramp. I love them both!
The first version is running on +-28 Volt railvoltage with Toshiba Jfets in the
BA-3 frontend,
the second one is running on a very high +-34.5 railvoltage with Linearsystems Jfets in the BA-3 frontend.
For me there is no real difference in sound between my two versions.
I can strongly recommend the use of the matched LinearSystems JFets from DIYAudio-store! (especially for beginners).
I used 1 Ohm bias resistors in my builds (I was thinkig about the change to 0.47 Ohm). My Mosfets are matched carefully.
I also tried different outputcaps in the BA-3 frontend. Not that much difference
for me in sound. I would say marginal.
I use my BA-3 poweramps with different preamps.
BA-3 preamp (lots of gain!), Waynes linestage (one of my favourite preamps at the moment; also as Headphoneamp), Aleph P1.7 preamp (also very good combo).
If I use single-ended preamps like B1-NUTUBE, B1-buffer-preamp, BOSOZ,
and other Nelson Pass-pres it sounds also very good!
For me The BA-3 poweramp is a fantastic combination of clear, detailed sound without harshness. I use one BA-3 sometimes as subwooferamp (very nice!).
Built it carefully and take your time. Adjusting the BA-3 frontend will take its time (don't be too fast adjusting the pots P1/P2 if you bias it up!).
I am sure you will get a 'fat grin' on your face if you listen to this 'baby'.
the first time. Perhaps you will get some long nights listening through your
music collection.
Have fun!
Dirk
Hello andynor,
I have built 2 versions of the BA-3 poweramp. I love them both!
The first version is running on +-28 Volt railvoltage with Toshiba Jfets in the
BA-3 frontend,
the second one is running on a very high +-34.5 railvoltage with Linearsystems Jfets in the BA-3 frontend.
For me there is no real difference in sound between my two versions.
I can strongly recommend the use of the matched LinearSystems JFets from DIYAudio-store! (especially for beginners).
I used 1 Ohm bias resistors in my builds (I was thinkig about the change to 0.47 Ohm). My Mosfets are matched carefully.
I also tried different outputcaps in the BA-3 frontend. Not that much difference
for me in sound. I would say marginal.
I use my BA-3 poweramps with different preamps.
BA-3 preamp (lots of gain!), Waynes linestage (one of my favourite preamps at the moment; also as Headphoneamp), Aleph P1.7 preamp (also very good combo).
If I use single-ended preamps like B1-NUTUBE, B1-buffer-preamp, BOSOZ,
and other Nelson Pass-pres it sounds also very good!
For me The BA-3 poweramp is a fantastic combination of clear, detailed sound without harshness. I use one BA-3 sometimes as subwooferamp (very nice!).
Built it carefully and take your time. Adjusting the BA-3 frontend will take its time (don't be too fast adjusting the pots P1/P2 if you bias it up!).
I am sure you will get a 'fat grin' on your face if you listen to this 'baby'.
the first time. Perhaps you will get some long nights listening through your
music collection.
Have fun!
Dirk
to andynor
This is a pic, how I arranged the pcbs in one of my BA-3 amps.
One possibility. You can go many different ways.
I put the small bias -boards on top to have easy access to the trimpots.
My wires are circa 15cm long. I have no problems with noise.
But I don't use horn-speakers with extreme sensitivity. My speakers are
91dB/W/m.
Greets
Dirk
This is a pic, how I arranged the pcbs in one of my BA-3 amps.
One possibility. You can go many different ways.
I put the small bias -boards on top to have easy access to the trimpots.
My wires are circa 15cm long. I have no problems with noise.
But I don't use horn-speakers with extreme sensitivity. My speakers are
91dB/W/m.
Greets
Dirk
Attachments
My current 2018 LS has Browski's PS from Tubecad site. I building another with the new board and am planning on the VRDN PS for it, I have the board, but some kind of shunt supply is also sounding interesting.
Russellc
So, I finally finished my BOM and ordered all FE and output bord parts. I’ll soon have all the tools I need too. So a long planning process is coming to and end, and hopefully I’lll get to soldering soon.
Or de-soldering, for that matter. This picture is from the PSU. I originally bought a failed F5T project, but it will now become a BA-3. as you can see, some strange choices have been made. Notice the extra big 0,47R resistors touching the caps. Also notice the bleeder resistors are of the none fireproof type, as far as I can tell. And the soldering work is not very successful IMO.
Makes me wonder if the PSU at some point was the reason for my predecessors failed project.
So I decided to redo the PSU, leaving only the caps. Those were installed by someone more competent than the original project owners. Only question now is, will I be able to do it better?
I hope so.
Still not decided whether to remove the caps IOT clean up the mess on the PCB. Guess I might have to.
If the board is trashed and possibly problematic you could remove the caps and replace board. I'm sure the store's PS board is fine, many here have used it. I have not. (yet) I have used in all my builds (but 1st build, F5) Teabag's PS board. Built like a tank. One downside, it isnt the smallest one out there, I believe the store's board is smaller.
This may be important if planning dual mono build where space is limited. My F5 mentioned above used Peter Daniels PS board, they are the most compact I've come across. Not sure if he is still selling them, maybe gerbers are around? They only use 4 caps, I think I used 33,000 uF. Tea's house 8, but I built F5 dual mono.
My BA3 is not dual mono, but one stiff supply, SUMr 1000 VA 24/24 volt transformer (originally obtained in F5 turbo kit group buy) and Tea's PS board with 8 33,000uF caps.
Russellc
Remove the Jfets and test. What board does this F5 thing use? I ask because at one time I assembled F5 turbo boards, I believe came from teabag. In fact, I may have an unused set of those boards around here somewhere. When I decided to build BA3 instead, I sold them to someone back then. These boards are thicker than normal and a little difficult to unsolder. The boards were white in color. The boards as sold had Toshiba matched J fets from Spencer. (known good). Dont know what thet went through after that....
Russellc
You are going to be one happy listener. If you like vinyl, add the Pearl 2 to your mix. I still remember the day I finished BA3 FE, BA3 amp and added Pearl 2. This combo jumped my system up LOTS of notches!
As impressed as I was with F5, ( that revelation of what could be done DIY allowed me to sell off all my tube stuff including my beloved MC 225 tube amp.) the BA3 struck me as a more "mature" amp design with lots of possibilities. P3 manipulation ( which current F5 boards also allow) building balanced, mono blocks etc.
Russellc
Hello andynor,
I have built 2 versions of the BA-3 poweramp. I love them both!
The first version is running on +-28 Volt railvoltage with Toshiba Jfets in the
BA-3 frontend,
the second one is running on a very high +-34.5 railvoltage with Linearsystems Jfets in the BA-3 frontend.
For me there is no real difference in sound between my two versions.
I can strongly recommend the use of the matched LinearSystems JFets from DIYAudio-store! (especially for beginners).
I used 1 Ohm bias resistors in my builds (I was thinkig about the change to 0.47 Ohm). My Mosfets are matched carefully.
I also tried different outputcaps in the BA-3 frontend. Not that much difference
for me in sound. I would say marginal.
I use my BA-3 poweramps with different preamps.
BA-3 preamp (lots of gain!), Waynes linestage (one of my favourite preamps at the moment; also as Headphoneamp), Aleph P1.7 preamp (also very good combo).
If I use single-ended preamps like B1-NUTUBE, B1-buffer-preamp, BOSOZ,
and other Nelson Pass-pres it sounds also very good!
For me The BA-3 poweramp is a fantastic combination of clear, detailed sound without harshness. I use one BA-3 sometimes as subwooferamp (very nice!).
Built it carefully and take your time. Adjusting the BA-3 frontend will take its time (don't be too fast adjusting the pots P1/P2 if you bias it up!).
I am sure you will get a 'fat grin' on your face if you listen to this 'baby'.
the first time. Perhaps you will get some long nights listening through your
music collection.
Have fun!
Dirk
You answered a question I've had for a while. I also use elevated rails, 24/24 giving about 32 volt rails. I have only used Toshiba J fets, good to know the LS versions also withstand these higher rails.
Russellc
Just to clarify, BA-3 amplifier is not a buffer. (F4 is a buffer with no gain, perhaps you are thinking of that...)
BA-3 amplifier has about 15db gain.
B1 buffer has no gain, but B1K NuTube has gain.
Iron pre has 6db/12db as noted, and works very, very well with BA-3 amplifier, and sounds an absolute treat.
It is a treat for sure. I'm surprised at only 15 db gain for BA3. Isnt F5 15 dB gain? Or do the higher rails give more gain? I didn't think so, but I'm wrong about this stuff regularly.
My BA3 sure seems to have more gain than either my F5 or M2. Aleph J seems to have a little more than those 2 as well. Oh well, learn something new every day!
Russellc
My BA3 sure seems to have more gain than either my F5 or M2. Aleph J seems to have a little more than those 2 as well. Oh well, learn something new every day!
Russellc
First off: thanks, man, for sharing your experiences and valuable info. Jeez, based on what you guys think of this amp, I just cant wait to get it up and running. So I stuffed all the small resistors in the FE in a vacant moment tonight. Gotta use my time wisely.
Can you give any more info about your Wayne LS build? Use PM if you prefer. I am thinking transformer and PSU choice. Still havent landed that... are the superregulators from the store complete PSUs sans transfomers? Silly question prolly, but unanswered still.
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Thinking Pearl 2, but not just yet. My Rega Planar 2 is not up to the task of being connected to a Pass construction with any hope of success. At least my old Krell revealed all it’/ flaws rather viciously...
So digital right now. To be honest, I sold off all my gear and started over - buulding myself. So BA-3 is first, then Waynes LS. Then I will have a look at source choice. Actually heard an opamp-free DIY DAC with a Raspberry PI as source a few weeks ago. Price VS performance VS work is hardly beaten wrt the PI. DAC is probably another game entirely...
A beautiful build. Truly! I am actually going to lay it out in generally the same manner, sans all the fancy and beautiful details =) I might also put the bias boards side by side the FE. And I am awaiting riser panels to mount the FE atop the PSU.This is a pic, how I arranged the pcbs in one of my BA-3 amps.
One possibility. You can go many different ways.
I put the small bias -boards on top to have easy access to the trimpots.
My wires are circa 15cm long. I have no problems with noise.
But I don't use horn-speakers with extreme sensitivity. My speakers are
91dB/W/m.
Greets
Dirk
Really valuable knowledge you are passing on. Thanks! BTW: decided on Waynes LS =)
So stuffing the front end, I ran into a couple of new things to ponder on and find out of:
P3: One of my P3s measure 52ohms when centered. The other 50 ohms. Is this an issue, and should I order a new pot? The other measures 50ohms flat on both pins.
Mosfet heatsinks on front end: The TO220 MOSFET can make the heatsinks conductive. If so, should i have the heatsinks mounted a few mm up from the PCB in order to avoid conducting to the PCB, or is this not an issue? It is hard to see from 6L6s pictures if the heatsinks are touching the PCB or not.
Regards,
Andreas
P3: One of my P3s measure 52ohms when centered. The other 50 ohms. Is this an issue, and should I order a new pot? The other measures 50ohms flat on both pins.
Mosfet heatsinks on front end: The TO220 MOSFET can make the heatsinks conductive. If so, should i have the heatsinks mounted a few mm up from the PCB in order to avoid conducting to the PCB, or is this not an issue? It is hard to see from 6L6s pictures if the heatsinks are touching the PCB or not.
Regards,
Andreas