Salas hotrodded blue DCB1 build - Page 174 - diyAudio
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Old 17th March 2012, 11:56 PM   #1731
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Quote:
Originally Posted by Siberia View Post
ClaveFremen, do you mean current setting resistors?
No, the two 220K and 1M, see attachment.
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File Type: jpg DCB1 buffer.jpg (30.0 KB, 258 views)
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Old 18th March 2012, 08:37 AM   #1732
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Dario, I've tried carbon films and other resistors in those and all critical positions previously. You are right, carbon films sounded bolder. But I prefer "nakeds" for their uber transparency. My problem is on bigger scale than mere tonality...

I wonder could it be heard on the file I have attached?

Salas, I've just followed your advice. Signal wires straight to pcb under it. Same sound.

I wonder also if could it be an amp related problem. For example bad amp rca connection?
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Old 18th March 2012, 12:14 PM   #1733
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If I had to describe what sound I'm getting, I would say it's all perfect except that somebody turned down low region knob on invisible eq.
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Old 18th March 2012, 01:09 PM   #1734
Salas is offline Salas  Greece
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Quote:
Originally Posted by Siberia View Post

I wonder also if could it be an amp related problem. For example bad amp rca connection?
Weird stuff. Since its about anemic low region you are right to suspect possible power stage related issues also. A DC line stage why to periodically cut on bass if all healthy its beyond me. You need some tech tests and related equipment data so we can really say for that system as a whole. Or some luck with trial and error on connections and parts.
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Old 18th March 2012, 01:13 PM   #1735
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Quote:
Originally Posted by Siberia View Post
VACin -16.60; +16.72
DCout -1.6; +0.9
I don't understand these measurements.
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Old 18th March 2012, 01:18 PM   #1736
qusp is offline qusp  Australia
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I presume thats supply voltage for the rails and DC offset (signal) at the output, not exactly the most intuitive way to write it
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Old 18th March 2012, 01:40 PM   #1737
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Quote:
Originally Posted by AndrewT View Post
I don't understand these measurements.
Tx secondaries: 16.60V; +16.72
-1.6; +0.9 is Dc offset on output.

Sorry, if it's counterintuive.
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Old 18th March 2012, 03:14 PM   #1738
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On my suspicion list one power amp rca which feels to have a looser connection then the other. I can tighten the plugs to grip well, but I wonder could it create the problem where "the nose" of connector it's not touching properly the conductor inside the socket?
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Old 18th March 2012, 03:32 PM   #1739
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I finaly managed to complete my Tea-bag Kit Dcb1 build.
The kit was very easy to use, and everything seems to work also!

I do have one measurement that is kinda well... Weird.

My Vout+ and Vout - are almost the same. 9.95V and 9.94V. What I read in the manual the Vout + should be higher then Vout- ? Is this bad?

The rest of the measurements:

Voltage drop on the power resistors: 1.764V and 1.861V

The output: Right 1.6mV dc
The output: Left 1.8mV dc

Led string -9.31V and +9.32V

I am using btw a 12v transformer, (for testing) would a 15 volt one be preferred?
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Old 18th March 2012, 03:54 PM   #1740
Salas is offline Salas  Greece
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In Hypnotize both rails tracking close is the right thing. In Mezmerize a bit apart is the right thing. So yours is OK. To tell if your OK with your Tx on your mains, give us the DC in value. You can measure it under one of the big filter capacitors.
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