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Old 8th May 2012, 06:36 PM   #11
Zen Mod is offline Zen Mod  Serbia
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atten doesn't have influence on gain

I already wrote few times what's needed to decrease gain of SL10

if you can't find these posts , buzz and I'll repost sch and procedure

check resistance (with ohmmeter) between L&R hots prior and post selector
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Old 8th May 2012, 06:54 PM   #12
PKI is offline PKI  United States
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Ok, got it. Yep, of cause not gain wrong word, sorry. I will check resistance today. Another thing, I already bought a PCB of B1, cause I would like to replace the SL-10 with B1 and pearl 2, do you think I will "gain" :-) in sound quality compare to sl-10?
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Old 8th May 2012, 07:07 PM   #13
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regarding gain issue - look at attached schm - for 6db gain decrease - either double in value 750R or halve in value 18K2 (both marked red)

B1 vs. SL10 .......

do not underestimate old geezers

B1 is welcome in your system if your sources are capable to drive power amp directly , swing-wise
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Last edited by Zen Mod; 8th May 2012 at 07:27 PM.
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Old 8th May 2012, 07:21 PM   #14
PKI is offline PKI  United States
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Quote:
Originally Posted by Zen Mod View Post
regarding gain issue - look at attached schm - for 6db gain decrease either double in value 750R or halve in value 18K2 (both marked red)

B1 vs. SL10 .......

do not underestimate old geezers

B1 is welcome in your system if your sources are capable to drive power amp directly , swing-wise
Thanks! Ok, I see for B1 vs sl-10 it is quite predictable, but what about phono stage of SL-10 vs Pearl 2? Have Mr. Pass and others improved it after ~30 years?
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Old 8th May 2012, 07:27 PM   #15
Zen Mod is offline Zen Mod  Serbia
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Pearl is better
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Old 9th May 2012, 01:26 AM   #16
GaryB is offline GaryB  United States
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Quote:
Originally Posted by Zen Mod View Post
regarding gain issue - look at attached schm - for 6db gain decrease - either double in value 750R or halve in value 18K2 (both marked red)
The schematic has a minor error compared to my SL10. The volume pot in my SL10 is 22K, not 10K. But your answer is still fine.
Another way of reducing the gain is to increase the value of the 1K resistor in series with the volume pot. Increasing it to ~12k will decrease gain by about 6db if your unit has a 10K pot. If your unit has a 22K pot then increasing the resistor to ~24K would drop the gain by 6db.

---Gary
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Old 9th May 2012, 05:20 AM   #17
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I prefer to decrease CLG of stage , not further weakening of signal ......... doing same thing as with pot on 8,5h

name of the game is - signal energy preservation , not convenience of full shaft rotation
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Old 9th May 2012, 05:37 AM   #18
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So, I've checked resistance between hot R and L and it is zero(within the accuracy of my meter). Hm... From what should I start to find the reason -- desilder all the switches and attenuator and check them?
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Old 9th May 2012, 05:50 AM   #19
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where exactly you took measurements ?
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Old 9th May 2012, 01:15 PM   #20
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So, I've checked resistance between hot R and L and it is zero(within the accuracy of my meter). Hm... From what should I start to find the reason -- desilder all the switches and attenuator and check them?
try the same with the balance a little offset.
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