Joyo - JF-17 Extreme Metal [gut shots]

All about modern commercial stompbox circuits from Electro Harmonix over MXR, Boss and Ibanez into the nineties.
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Post by marmaliser »

Sanded IC's intriguing :scratch: Looks like a EHX Metal Muff. The fact that the Boost feature is almost unusable due to the extra Treble and Noise added also makes me think its a Metal Muff.
Anyhow just for the record here are some pics
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Post by Scruffie »

Isn't the Metal Muff fairly simmilar to a BOSS HM-2 or MT-2... I don't know why but it seems less likely to me that they got the EHX schematic... maybe it's just me as the boost feature does give it away some.

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Post by greeny23 »

The only pedal with smd from joyo?
the toyroom effects guy.

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Post by Steven_M »

greeny23 wrote:The only pedal with smd from joyo?
No, there are quite a few. All of the Tech 21 rip offs are SMD also.

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Post by JiM »

marmaliser wrote:Sanded IC's intriguing :scratch:
This doesn't look like sanded to me, just dirty with flux residue. :mrgreen:
I only give negative feedback.

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Post by snabero666 »

Good day forumite,

Here's a mod that you can apply to extreme metal with great result. Extreme metal has the same distortion circuit with metal muff and boss mt2 with fix mid freq and additional boost circuit minus fet switch.So I try the mt2 no nasal sound mod. removing two capacitors C2 and C10 using cutter or nail puller.

here is some sound sample

the distortion will be dynamic and its more marshallish tone with great bass. the boost now makes the mid more pronounce or making it metal but still dynamic. This mod can be used at metal muff. good luck.

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Post by dimacotorobai »

hello!what is nominal of c51,c2 and c10 capacitors?

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Post by mccy »

Hi, I started building a digital clone of the Extreme Metal

and found that it is not as easy as I thought... Cod someone help me what's going on inside? There seems to be kind of parallell distortion to keep the Bass tight. I'd just need to understand the basic concept, the rest is earwork :-)...

best regards


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