Good evening,
not another finished build...
But a finished 2nd set of boards.This time with TOSHIBA 2SK209 GR in the first stage. I measure 0,022 V or 0,021 V over all 8
source-resistors (10 Ohm). So they are all running at 2.1 mA to 2.2mA.
I measure 3.03 V over R 27 (increased to 750 Ohm), so this equals circa 4mA. Looking good.
Offset at output is slightly fluctuating without load - anywhere around 1 - 3 mV. All good.
Bias of the TOSHIBA TTA/TTC004B is 0,255 V over the resistors R23/R24 (22 Ohm), so anywhere around 11.6 mA.
The balanced line driver is not stuffed for testing.
Did I mention, that it sounds really great from the start! No testing with cheap speakers - full risk and full pleasure! 😉
Cheers
Dirk
and sorry for the fotos - I made 'gymnastics' to measure in the circuit and taking fotos at the same time...
Why isn't there a third or fourth Hand, mother nature?
not another finished build...
But a finished 2nd set of boards.This time with TOSHIBA 2SK209 GR in the first stage. I measure 0,022 V or 0,021 V over all 8
source-resistors (10 Ohm). So they are all running at 2.1 mA to 2.2mA.
I measure 3.03 V over R 27 (increased to 750 Ohm), so this equals circa 4mA. Looking good.
Offset at output is slightly fluctuating without load - anywhere around 1 - 3 mV. All good.
Bias of the TOSHIBA TTA/TTC004B is 0,255 V over the resistors R23/R24 (22 Ohm), so anywhere around 11.6 mA.
The balanced line driver is not stuffed for testing.
Did I mention, that it sounds really great from the start! No testing with cheap speakers - full risk and full pleasure! 😉
Cheers
Dirk
and sorry for the fotos - I made 'gymnastics' to measure in the circuit and taking fotos at the same time...
Why isn't there a third or fourth Hand, mother nature?
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It looks like the post or customs people were envious and wanted to see your kit first. I hope everything made it in good condition and they didn’t keep a souvenir
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OK, I'll bite.... I'm ready to put the Bursons in the P3... after that I'll keep the box open. I'm happily willing to play Mark's game.
Life has a way of getting in the way... at least the XZ252 SIT affair seems to have settled... so that's no longer taking my time.
How do we do this?
I've been wondering how to approach the op amp rolling. The Maggies superimpose their sound on most things. The Audio Notes are a better... but I've been thinking that using the Acoustic Energy with the Entecs might be the best because those are true monitors that clearly reflect what's ahead in the chain.
Also, what amp? Would I go with a class A, tubes? Or maybe a drop dead accurate amp? I do have a nice Nuforce STA200 (based on the Job amp) that is very good for such things and it drives the AE1 very well.
I guess to play this game, I need to figure out some rules. Do I play this game to hear the differences or do I play this game to see what I like?
Ideas?
Life has a way of getting in the way... at least the XZ252 SIT affair seems to have settled... so that's no longer taking my time.
How do we do this?
I've been wondering how to approach the op amp rolling. The Maggies superimpose their sound on most things. The Audio Notes are a better... but I've been thinking that using the Acoustic Energy with the Entecs might be the best because those are true monitors that clearly reflect what's ahead in the chain.
Also, what amp? Would I go with a class A, tubes? Or maybe a drop dead accurate amp? I do have a nice Nuforce STA200 (based on the Job amp) that is very good for such things and it drives the AE1 very well.
I guess to play this game, I need to figure out some rules. Do I play this game to hear the differences or do I play this game to see what I like?
Ideas?
If you are opamp rolling yourself, there are no “rules”, as it’s sighted changes, and just report back with what you like.
🙂
🙂
OK. Mark, can you please PM the specifics?
Oh, I was told that the sockets in my boards might be a tad too small.... I guess it needs larger sockets. Gimme a day to figure out if I can fit the Bursons, if so, I guess we'll be set.
Oh, just thinking... I got the Burson Play DAC which is also made for op amp rolling... right now it has the v6 Classics - before it was running the V5. I also got a Burson "Supreme Sound Lycan" which was specifically made for listening to the sound of op amps..
https://6moons.com/audioreviews2/supremesound/1.html
I guess it just happens that I'm actually well set to roll opamps... ;-)
Oh, I was told that the sockets in my boards might be a tad too small.... I guess it needs larger sockets. Gimme a day to figure out if I can fit the Bursons, if so, I guess we'll be set.
Oh, just thinking... I got the Burson Play DAC which is also made for op amp rolling... right now it has the v6 Classics - before it was running the V5. I also got a Burson "Supreme Sound Lycan" which was specifically made for listening to the sound of op amps..
https://6moons.com/audioreviews2/supremesound/1.html
I guess it just happens that I'm actually well set to roll opamps... ;-)
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A couple questions about the PSU.
If using the UDP3, should a Ground Loop Breaker of some sort be added? I know @rhthatcher’s board has one built in.
Also, might be a dumb question, but could the VRDN be used to power a P3? I have a board set up to be used with a Wall Wart and 18Volts. Curious if it could be used in the same chassis since a transformer isn’t used. Just a thought.
Thanks.
If using the UDP3, should a Ground Loop Breaker of some sort be added? I know @rhthatcher’s board has one built in.
Also, might be a dumb question, but could the VRDN be used to power a P3? I have a board set up to be used with a Wall Wart and 18Volts. Curious if it could be used in the same chassis since a transformer isn’t used. Just a thought.
Thanks.
Awesome! Thanks Jim.
Would be cool to find a way to implement the P3 and Wayne’s preamp into the same chassis off the same PSU.
Would be cool to find a way to implement the P3 and Wayne’s preamp into the same chassis off the same PSU.
That would be easy. Set VRDN or similar regulated PSU to 18V, and power everything from it. BA2018 will be more than happy on 18v, and the Pearl regs will have enough voltage on the inputs to operate properly. Win-win.
I plan during the weekend to solder the 2 x 4 small smd capacitors.
I put them in a small plastic box just to ensure they don't "run away". But a small accident happened! .....one capacitor jumped to the table.
It took several minutes to locate him and put him back. I can't recommend to drop any of these. Dropped at the floor you can consider it dropped forever!
Just a warning. Don't drop them 🙂
I put them in a small plastic box just to ensure they don't "run away". But a small accident happened! .....one capacitor jumped to the table.
It took several minutes to locate him and put him back. I can't recommend to drop any of these. Dropped at the floor you can consider it dropped forever!
Just a warning. Don't drop them 🙂
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SMD parts -
In the kits you will find that there’s (9) 2SK209 Jfets. One extra just in case you sneeze.
There are only (8) of the 1uF capacitors, as the vast majority of builders are not going to stuff the balanced line driver, if you happen to lose one, order an extra when you order the DRV135. Whereas if you don’t use the balanced line driver, you’ll have enough capacitors.
In the kits you will find that there’s (9) 2SK209 Jfets. One extra just in case you sneeze.
There are only (8) of the 1uF capacitors, as the vast majority of builders are not going to stuff the balanced line driver, if you happen to lose one, order an extra when you order the DRV135. Whereas if you don’t use the balanced line driver, you’ll have enough capacitors.
When ordering parts for SMD boards, I make it a habit to order either ($2.00 worth of extra parts) or (3 extra parts), whichever calculation yields the greatest quantity. For each SMD line item on the parts list.
It seems to me this is "cheap insurance" compared to the shipping cost and DELAY of re-ordering after misplacing a dropped component.
It seems to me this is "cheap insurance" compared to the shipping cost and DELAY of re-ordering after misplacing a dropped component.
I see......I will reconsider installing the line driver. I should probably wait until I will need it. I have installed the XLR's (expensive "blind-plates"). It is first now I realize that a speciel line-driver is needed for the SE to BAL conversion (it is written in the build doc) and not just a dual op amp. Then R32 is not needed either.
Maybe solder the smd opamps and preparing the resistors. Some of those needs a bit of pairing 🙂
Need to do a bit of power lifting in the gym and maybe watching handball EU championship from Germany as long as Denmark is still in the game 🙂
I think I will use the LSK170A octet I purchased some years ago from DIY shop. They should be 0.9 nV/Hz-2 (as quiet as 2SK170). But that will be after all the resistors have been populated. Think this will be the perfect project for an octet of LSK170A.
Need to do a bit of power lifting in the gym and maybe watching handball EU championship from Germany as long as Denmark is still in the game 🙂
I think I will use the LSK170A octet I purchased some years ago from DIY shop. They should be 0.9 nV/Hz-2 (as quiet as 2SK170). But that will be after all the resistors have been populated. Think this will be the perfect project for an octet of LSK170A.
Got started on both the P3 and Randy’s power supply group buy, and realized that my exuberant building of multiple Korgs had left me without any hookup wire left. How i didn’t notice must have been because the immediate return was so special…the Korg is a lovely pre.
Without delving into black magic, what are people’s preferences these days for brand and gauge?
In the meantime, i’m going to finish the boards and try to get some skiing in, even though it is raining and 51 degrees in the Berkshires.
Without delving into black magic, what are people’s preferences these days for brand and gauge?
In the meantime, i’m going to finish the boards and try to get some skiing in, even though it is raining and 51 degrees in the Berkshires.