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Old 8th August 2008, 04:03 PM   #431
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Quote:
Originally posted by Tolu
Then I will hoard them and in 20 years I will sell them as NOS parts to ensure my retainment pay!
That's my plan, go find your own.

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Old 10th August 2008, 10:46 AM   #432
BURNER is offline BURNER  Thailand
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Hi Choky

Sorry for stealing your idea

I modified B1 power supply (BZLS style; positive side, IRFP240 instead of IRF610), replacing zener stack with 12 x small-green-LED stack.

The output is nicely stabilized at +19.4V

About the sound ...
Running LED-powered B1 with F5, it's huge improvement
* Mid seems to be warmer & sweeter
* High is more relaxed and silky
* Cleaner bass

Listen to a track 3 "High Life" of CD: Jazz at the Pawn Shop Vol.1 is a spooky experience as every instruments got better shape and focus !

Thanks for sharing your experiences

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Old 10th August 2008, 11:05 AM   #433
Zen Mod is offline Zen Mod  Serbia
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Quote:
Originally posted by BURNER
Hi Choky

Sorry for stealing your idea.............

yup ; I certainly invented that

when you have time - try B1 with split supply ( +/- 9V ) ;

you'll get rid of input cap , and even better supply rejection
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Old 10th August 2008, 12:50 PM   #434
Skorpio is offline Skorpio  Denmark
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How critical is B1 layout corcerning stability?

Specially input and output wires....could the be close without problems?
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Old 10th August 2008, 01:13 PM   #435
Zen Mod is offline Zen Mod  Serbia
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Quote:
Originally posted by Skorpio
How critical is B1 layout corcerning stability?

Specially input and output wires....could the be close without problems?

no more than any other low gain stage ;

so - keep those wires as much apart you can
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Old 10th August 2008, 01:43 PM   #436
Tolu is offline Tolu  Germany
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Default Re: Basically what I have done by now

Quote:
Originally posted by salas
Found some spare time, and populated the perf-board. Done half the point to point also. I am putting together 1 positive & 1 negative regulated PSU, 1 output delay relay circuit and 2 channels of capacitor-less B1s. Hopefully in the next few days I will find time to finish it and test it little by little. Will report.
Next post includes the awfully sketched schematic.
Hi Salas

any listening experience yet?
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Old 10th August 2008, 04:49 PM   #437
Salas is online now Salas  Greece
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Had work to do and I left this little project behind. I will have to finish the point to point soldering and put it in a small plastic box along with a pot and connect it up so to see about offset behavior and square waves so to adjust resistors and PSU trimmers if needed. Then I will listen. If spare time is found, I will be ready to report everything in a couple of days.
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Old 10th August 2008, 07:18 PM   #438
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I saw with some interest, that a solution for a active crossover was possible with this simple and hopefully good sounding buffer. For a start I would like to make a active low pass crossover with 12db at 150 Hz.

I just added another B1 and placed R7 + R8 and C4 + C5 between the two B1's.

Is that all? Or are there more into it?

Click the image to open in full size.

It is 6.8 db down at 150 Hz compared to the -20dB input, so it looks promising.

Click the image to open in full size.
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Old 10th August 2008, 07:37 PM   #439
Skorpio is offline Skorpio  Denmark
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Quote:
Originally posted by stigaard123
I saw with some interest, that a solution for a active crossover was possible with this simple and hopefully good sounding buffer. For a start I would like to make a active low pass crossover with 12db at 150 Hz.

I just added another B1 and placed R7 + R8 and C4 + C5 between the two B1's.

Is that all? Or are there more into it?

Click the image to open in full size.

It is 6.8 db down at 150 Hz compared to the -20dB input, so it looks promising.

Click the image to open in full size.

I think your C4 should be connected to output instead of ground to get it right...
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Old 10th August 2008, 07:47 PM   #440
Zen Mod is offline Zen Mod  Serbia
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Default deja vu ?

Quote:
Originally posted by stigaard123
I saw with some interest..........

http://www.diyaudio.com/forums/showt...59#post1555159
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