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Old 6th April 2012, 05:38 PM   #21
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Just as one data point, my bias would go up about 20-30mV with the cover off vs. with the cover on.
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Old 6th April 2012, 05:43 PM   #22
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Quote:
Originally Posted by dantwomey View Post
The high end is softened and less detailed and lacks the sparkle of my gainclone. If I could restore this sparkle and detail without any accompanying glare this would take the F5 up a notch for me.
If it's a stock F5, you may improve it by removing current limiting circuitry.
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Old 6th April 2012, 05:55 PM   #23
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Quote:
Originally Posted by Peter Daniel View Post
If it's a stock F5, you may improve it by removing current limiting circuitry.
This shows also an increase of gain
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Old 6th April 2012, 07:38 PM   #24
a.wayne is offline a.wayne  United States
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Originally Posted by dantwomey View Post
Actually my speakers are 10 ohm in a very large (18' x 27') room.

Click the image to open in full size.

Click the image to open in full size.

Click the image to open in full size.
The 10 ohm maybe your problem , you have 22 watts to drive your speakers ...
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Old 6th April 2012, 08:27 PM   #25
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Two updates. After a brief investigation the lack of power seems to be my preamp. More on that soon.

As for the lack of sparkle. For the last couple of years I had a series of 'bright' amps so I toned down the HP crossover on my line arrays. I may look at reversing those changes to see if it helps my F5.

None of my line array pics have my F5 in it. New pics of my F5 soon.

Regards,
Dan
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Old 6th April 2012, 08:34 PM   #26
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Quote:
Originally Posted by Peter Daniel View Post
If it's a stock F5, you may improve it by removing current limiting circuitry.
This is the circuit I built. I didn't realize I could eliminate R7 and R8. I didn't measure voltage drop across R3 and R4. I just made sure the Vdrop across R11 and R12 was 600mV and DC offset on the output was near zero.

Regards,
Dan

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Last edited by dantwomey; 6th April 2012 at 08:42 PM.
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Old 6th April 2012, 08:45 PM   #27
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IME sparkle, shimmer, sizzle, etc are undesirable and suggest distortion or noise. The cleaner my top end has become, the 'darker' and 'richer' overall the sound has become, while the treble is smoother and more delicate and revealing than ever, and the sound also has better micro dynamics, making it sound louder and more explosive at the same volume setting as previously -- like live sounds.

(A couple of weeks ago, I went from CRC to CLC on my class AB amp and cannot believe the improvement everywhere....!)
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Old 6th April 2012, 09:04 PM   #28
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Originally Posted by dantwomey View Post
This is the circuit I built. I didn't realize I could eliminate R7 and R8.
The F5 circuit you built doesn't have the current limiting that the 'original' F5 has.
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Old 6th April 2012, 09:30 PM   #29
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Originally Posted by Andersonix View Post
IME sparkle, shimmer, sizzle, etc are undesirable and suggest distortion or noise. The cleaner my top end has become, the 'darker' and 'richer' overall the sound has become, while the treble is smoother and more delicate and revealing than ever, and the sound also has better micro dynamics, making it sound louder and more explosive at the same volume setting as previously -- like live sounds.

(A couple of weeks ago, I went from CRC to CLC on my class AB amp and cannot believe the improvement everywhere....!)
Which amp ....? Differences noted ? CLC values would be appreciated ....
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Old 6th April 2012, 09:56 PM   #30
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Which amp ....? Differences noted ? CLC values would be appreciated ....
CRC to CLC update here
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