Joyo - JF32 Hot Plexi

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Joyo - JF32 Hot Plexi

Postby Stone_66 » 17 Aug 2015, 18:49

induction wrote:The PlexiTone uses 4 op-amps. According to Fender56, this is an LM386 driven by an op-amp. Based on that alone, I think nickthemen is probably right, it's a Lovepedal Purple Plexi, possibly with an op-amp input buffer.


Hi, Fellas [smilie=rlp_smilie_242.gif]

Just to add a little more infos, I took some gutshots from my own Hot Plexi, that I'll post here later. In fact, this box is a variation of a Lovepedal Purple Plexi since it carries a JRC386 chip (hidden by the tone pot, barely visible on the circuit board). The added "tubescreamey" JRC4558 chip to the circuit sums a new (old) fashion tone to the overall sound of the pedal. Reading a lot of other posts over the internet made me believe at first, this box was nothing more than a clone or a cross between Carl Martin Plexitone Single and the Wampler Plexi Drive, both great pedals, in my opinion. It even has the same visual as CM. This way, I hope I could find some J201's or even the LF347 on board. But, to my surprise, nothing but the mighty 4558 and the 386 was sharing together the same board, what made me a bit confuse. What made Mr. J. Wong mix the two chips on the same project? I don't know, but to me, that combo made me very happy for two main reasons. First, I liked the sound very much. Think of a Plexitone on steroids (or a turbo charged Tube Screamer, you name it!). Second, this is not a mere clone of a famous boutique pedal, but an upgrade of it, that sounds pretty good, at a fair price :applause:

I'm coming over with the pics, soon.

Cheers from Brazil :cheers

Gustavo

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Re: Joyo - JF32 Hot Plexi

Postby Stone_66 » 23 Aug 2015, 23:30

The pics...

Backboard. Alpha pots. Nice.
Image

The booster. Nice touch, a 4558. The main reason this box isn't a mere clone of the Lovepedal.
Image

The "hidden" 386.
Image

General view of the front board.
Image

Hope it helps :thumbsup

Cheers.

Gustavo

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Re: Joyo - JF32 Hot Plexi

Postby modman » 24 Aug 2015, 18:46

Subject: Lovepedal - Purple Plexi 800 [goop-alarm]
minatour87 wrote:by your request
The pots are Level-100K, Freq-5K, and Gain-1K.
peace minatour87


Subject: Lovepedal - Purple Plexi 800 [goop-alarm]
minatour87 wrote:while looking at a krank distortus maximus schematic, it flashed in my mind that the
IC under the epoxy is a LM386. Therefore, it seems like everyone has said a COT50 with a boost and eq.... peace minatour87


:hmmm:

now what with the 4558?

edit: is the JRC386 at all connected to anything...
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Re: Joyo - JF32 Hot Plexi

Postby Stone_66 » 24 Aug 2015, 20:53

is the JRC386 at all connected to anything...


As soon I have some extra time, I'll try to get better pics to post here. I need to reopen the box also, so this could be a pain to do :thumbsup

Cheers
Stone

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Re: Joyo - JF32 Hot Plexi

Postby Stone_66 » 11 Jul 2018, 17:04

Hi fellas.

Almost 3 yrs after the last post, here I go again to show more Joyo HP gutshots. This time, after using this fabulous pedal during all those years I decided to mod it, with the simple 100k resistor soldered between the volume and tone pots, an old mod that everyone knows. As I had to open the box to mod the circuit, I took some extra pics to reveal the secret behind the "soldered to nothing" illusion that we have when looking to the components on the board. I decided to back lit the board to show you that, in fact, the board is some kind of "dual layer", or anything like that, giving us the impreesion that the components weren't soldered properly to the board.

The pics:

Image

Image

Image

Image

Image

Image

This pedal is a champ, I hope someone could trace the board for a DIY. Although it carries a 4558 as a buffer or a pre amp prior to the 386, the pedal loaded with a Tube Screamer type effect shines far better... I read somewhere that this pedal is preferred than a Wampler Plexi Drive or Pinnacle, but I can't say nothing since I never tried those effects.

Hope it helps.

Comments, please... [smilie=a_goodjob.gif]

:cheers

Gustavo (Stone_66)
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Re: Joyo - JF32 Hot Plexi

Postby jazzjagger » 21 Oct 2018, 19:23

Thank you Sir!

You are great!

:D
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