Filter Cap Values and Brands for Blues Jr. Clone

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joel_ostrom
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Location: Calgary, Alberta

Filter Cap Values and Brands for Blues Jr. Clone

Post by joel_ostrom »

I pulled apart my Blues Jr. last night to poke around inside the chassis. I'm planning to make an inventory of the parts and hopefully do a little PTP clone project of it, but i was wondering about the filter caps and their values.

The 3 biggest ones were rated at 22uF @ 450V - but i was having a difficult time finding caps that were rated exactly for that on a few of my regular online suppliers (Watts Tube Audio, Small Bear etc.).

Is it imperative to the function of the amp to have caps rated for the exact same value? I understand that different cap values will obviously affect the tone/response of the amp. I'm just wondering if different cap values will interfere with the voltage flow and possibly cause an overheat or blowout.

Where could i go to read up on caps, resistors and diode basic knowledge and how they interact within a circuit? Any good websites or books i could get?

Cheers,
Joel
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martin manning
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Re: Filter Cap Values and Brands for Blues Jr. Clone

Post by martin manning »

The value of the component, 22uF in this case, is the primary concern. The voltage rating can be the same or higher so 22uF @ 500V, for example, would be fine. For general background information, you might search "electrolytic capacitors" to find some published tutorials and application notes from manufacturers. Searching "capacitor types" will get you some discussion on the differences between capacitors made of different materials (and a lot of opinions on the sound qualities). For something more specific, Randall Aiken's site http://www.aikenamps.com/ has a number of excellent technical articles related to guitar amp electronics, including some discussion on component types.
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Structo
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Re: Filter Cap Values and Brands for Blues Jr. Clone

Post by Structo »

Tom

Don't let that smoke out!
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