Harmony H307X project

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Tumtrah
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Harmony H307X project

Post by Tumtrah » Fri Mar 12, 2021 11:23 am

Traded this Harmony amp in for an accutronics reverb tank. It has a broken cabinet, changed/modified circuit, non original OPT, knobs and speaker.
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jthomas
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Re: Harmony H307X project

Post by jthomas » Fri Mar 12, 2021 3:18 pm

Looks like a fun resto project.

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Tumtrah
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Re: Harmony H307X project

Post by Tumtrah » Sat Mar 13, 2021 1:29 am

It's a lightweight amp due to the cabinet which is build out of soft fiber/soft board (don't know how it's called in English). At first I thought I would build a new one, but i can do that later and try to fix it.
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tribi9
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Re: Harmony H307X project

Post by tribi9 » Sat Mar 13, 2021 8:57 am

Tumtrah wrote:
Sat Mar 13, 2021 1:29 am
It's a lightweight amp due to the cabinet which is build out of soft fiber/soft board (don't know how it's called in English). At first I thought I would build a new one, but i can do that later and try to fix it.
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Its called particle board.

Good stuff. You should do up a new cabinet though. Particle board sucks.

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Tumtrah
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Re: Harmony H307X project

Post by Tumtrah » Sat Mar 13, 2021 11:55 am

Thanks for the definition! Due to the porous material I tried polyurethane glue to fix the cabinet and it seems to work.
Maybe particle board sounds good? :unsure: Nevertheless this will not be my amp for gigs...

I did some research and found two usefull links to reconstruct the circuit:
https://oldamps.weebly.com/harmony-h307x.html
https://lectrolab.wordpress.com/lectrolab-models/r600/
The Lectrolab R600C is circuitry-wise identical to the Harmony H307X.

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fenderheavy
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Re: Harmony H307X project

Post by fenderheavy » Sun Mar 21, 2021 9:21 pm

Good trade! Never heard of that model.

I have it’s more common sibling, the H306A. Got it for free about 20 years ago when I was picking up an old organ from a craigslist free ad. “Do you possibly have any other musical equipment?” Kind of deal.

Great sounding amp! You’ll dig it.

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Tumtrah
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Re: Harmony H307X project

Post by Tumtrah » Mon Apr 05, 2021 10:57 am

Meanwhile the cabinet is fixed.
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The damaged clothing is clearly visible but for now I will leave it as is.
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Installed a (chinese?) Cream alnico speaker:
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Re: Harmony H307X project

Post by Tumtrah » Fri Apr 09, 2021 8:47 am

A look under the hood. Hefty modified... :wtf: I'll have to gut the whole chassis and redo the electronics.
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There is a fragmentary schematic on the back panel.
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New chickenheads arrived. :)
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