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It is currently 06 Dec 2019, 05:26

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PostPosted: 10 Nov 2019, 11:34 
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Joined: 11 Sep 2019, 10:56
Posts: 13
Hi,

Finished my Forewatt and hooked it up but I'm not getting any amplification and it seems to act more like a filter. I have 215v on the B+, 6vdc on the heaters with no tube in bug that drops to about 4.8v with the tubes in. There's no earth hum. There's no great change in volume when the volume pot is rotated but there does seem to be a change in tone. I've checked the circuit several times and all seems to be in the right place.

Can anyone suggest what I should check to try and get itvworking properly?

Thanks

Rog


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PostPosted: 13 Nov 2019, 21:29 
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Joined: 04 Jun 2008, 20:59
Posts: 4052
Location: Arizona, USA
Hi, It sounds as if you have somehow either connected something incorrectly or that you have bypassed the acitive part of the circuit. Sometimes incorrect component values can cause this too. To help more....please attach a copy of the exact schematic you used to build it and note anything you did that was different from it. That way we can talk about exactly what to test to resolve the problem.

Good listening
Bruce

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PostPosted: 15 Nov 2019, 15:38 
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Joined: 11 Sep 2019, 10:56
Posts: 13
Actually it works fine...my misunderstanding that it was a line preamp and not a phono one. Plugged in between my CD player and solid state amp..wow! It's the audio equivalent of putting on glasses when you're short sighted. Great detail and separation. Crisp highs and authority to the bass. My benchmark Is the drums on Rickie Lee Jones' 'We Belong Together' and it outshines anything else I've heard in a long time. I am now really looking forward to hearing the Poddwatt when it's built.

Thanks for the circuit and the help

Rog


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PostPosted: 15 Nov 2019, 21:33 
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Joined: 04 Jun 2008, 20:59
Posts: 4052
Location: Arizona, USA
Hi, Yes that would happen. The companion phono preamp (Groovewatt project) is a killer as well IMO. Not a simple project though. I use them all the time.

Good listening
Bruce

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