Lovepedal - Purple Plexi 800 [goop-alarm]  [traced]

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dap9
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Post by dap9 »

This looks like a fun breadboard project. The provided scheme has a JRC386, but the descriptions indicate a LM386. Is there a huge difference? I only have some LM386 floating around. thanks.

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Post by Lawnchair »

Thanks Madbean! Gonna build this tomorrow as soon as my election hangover dissapates. [smilie=wine.gif]

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Post by dap9 »

I have it breadboarded, but no sound. BUT - I don't have Schottkys so I have a pair of 1N914s instead - I don't really know the difference yet so I'm hoping this is the problem as I think all the connections are there. If I do need the Schottkys, is there an appropriate substitute? I'll have to make a trip to Rat Shack tomorrow for Schottkys.

Thanks

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Post by dap9 »

:slap: :slap: :slap: :slap: :slap:

Had the diodes in 'backwards'. Working now. I didn't have a 1k pot for the gain so I have a 5k pot for now. It's late so I can't really crank it, but at lower volumes I'm noticing it's a bit bassy - but maybe when I can turn up, it'll even out.

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Post by audioguy »

I built this one from Madbeans layout. Sounds good BUT the gain control doesn't do much at all... no change in distortion (its starts off at medium high gain) until you're at 95% then it kicks into a nice higher gain.
If this can be smoothed out this things would be a really killer distortion box.

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Post by analogguru »

:shock: :shock: :shock:

I know that goop is expensive, but $ 175,-- for this chinese mass product ? :scratch:
https://cgi.ebay.com/LOVEPEDAL-PURPLE-PL ... 240%3A1318

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There´s a sucker born every minute - and too many of them end up in the bootweak pedal biz.

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Post by madbean »

audioguy wrote:I built this one from Madbeans layout. Sounds good BUT the gain control doesn't do much at all... no change in distortion (its starts off at medium high gain) until you're at 95% then it kicks into a nice higher gain.
Try a 1kC instead of 1kB if you have it. Smallbear has them.

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Post by audioguy »

Yeah thats what I was thinking as well

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Post by sandmannn69 »

dap9 wrote::slap: :slap: :slap: :slap: :slap:

Had the diodes in 'backwards'. Working now. I didn't have a 1k pot for the gain so I have a 5k pot for now. It's late so I can't really crank it, but at lower volumes I'm noticing it's a bit bassy - but maybe when I can turn up, it'll even out.
The original typically has a bassier sound when played through a 1x12 cab or combo than your standard, run-of-the-mill distortion pedal, which I think is what gives it that amp-like characteristic. Has a much bigger fuller sound, like you're running a 4x12 setup.

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Post by sandmannn69 »

audioguy wrote:I built this one from Madbeans layout. Sounds good BUT the gain control doesn't do much at all... no change in distortion (its starts off at medium high gain) until you're at 95% then it kicks into a nice higher gain.
If this can be smoothed out this things would be a really killer distortion box.
This is typical of the original pedal, too. Gain really jumps on the last 1/3-1/4 of the pot.
You have to tweak the frequency/voicing/tone whatever (middle) knob to hear the change in the gain thru the midrange of the gain pot adjustment.

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Post by dap9 »

sandmannn69 wrote:
audioguy wrote:I built this one from Madbeans layout. Sounds good BUT the gain control doesn't do much at all... no change in distortion (its starts off at medium high gain) until you're at 95% then it kicks into a nice higher gain.
If this can be smoothed out this things would be a really killer distortion box.
This is typical of the original pedal, too. Gain really jumps on the last 1/3-1/4 of the pot.
You have to tweak the frequency/voicing/tone whatever (middle) knob to hear the change in the gain thru the midrange of the gain pot adjustment.
What would you recommend to further tweak the circuit to bring up the mids and maybe some treble?

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Post by sandmannn69 »

dap9 wrote:
sandmannn69 wrote:
audioguy wrote:I built this one from Madbeans layout. Sounds good BUT the gain control doesn't do much at all... no change in distortion (its starts off at medium high gain) until you're at 95% then it kicks into a nice higher gain.
If this can be smoothed out this things would be a really killer distortion box.
This is typical of the original pedal, too. Gain really jumps on the last 1/3-1/4 of the pot.
You have to tweak the frequency/voicing/tone whatever (middle) knob to hear the change in the gain thru the midrange of the gain pot adjustment.
What would you recommend to further tweak the circuit to bring up the mids and maybe some treble?
I wouldn't tweak it, it sounds great to me (obviously). If you're looking for more mids/highs, I would suggest a Hao Rust Driver. That pedal nails the hot-rodded Plexi quack without the bottom end of the PP800. I put together a clone from https://i14.photobucket.com/albums/a303/ ... IVER-1.jpg that screams but is pretty much a one-trick pony. I'll let minotaur87 chime in on this one if he's not too busy babysittin my Valve Junior.

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Post by minatour87 »

for the mids and highs questions...

first thoughts,,, check the caps to ground... any larger value than what is called out would reduce the highs...

second thought.. looking at the data sheet for the LM386, check what is connected from pin 1 to pin 7, The data sheet has an example of a cap/resister between these pins puts a bass boost for the amp...PP800 clone calls out nothing connected to pin 7...

last thought.... there is a lot of variables to getting to that TONE. it is hard to hear what you are listening to for a reference....or what you are trying to sound like...

Up date on the Value Jr: just finished learning Sweet Leaf ... nice tone ...my hand is sore... to answer questions off topic, it is a dean custom through a krank distortion to the Value Jr. with mods....pretty close to Sabbath's tone...
peace minatour87

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Post by nooneknows »

OT:
sandmannn69 wrote:I would suggest a Hao Rust Driver. That pedal nails the hot-rodded Plexi quack without the bottom end of the PP800. I put together a clone from https://i14.photobucket.com/albums/a303/ ... IVER-1.jpg that screams but is pretty much a one-trick pony
a good one, indeed: I'm able to get a wide variety of good marshallesque sounds just turning the guitar volume knob... :)

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Post by chris_d »

I built this a few days ago from Torchy's vero ayout (many thanks once more for these Tochy!), and i must say, i am not too into the sound of it. It is o.k., but like the OCD i built earlier, i just don't feel it sounds all that good, or like a decent amp OD tone.

Folks who like this one, and/or the OCD, what amps are you running through? I am using what is essentially a modified Fender sort of homebrew amp, and i just don't like these pedals through it.

So far the best sounds i have gotten from a pedal are from the Zvex BOR, and the Timmy. Actually, the Timmy boosting into the BOR is, through my amp, a very good gainy sound, about as close to amp distortion as i have found, really.

Do these pedals respond better with marshall-like circuits, or what? I just find the distortion character to be oddly artificially grainy and buzzy. Actually, now that i thionk of it, i was not so psyched about the sound of the Clark Gainster i built either(though admitedly, i opted out of all of the "mojo" components on that one save the mica cap). Maybe my amp is just picky?

Hmm. I don't know. I am curious to know what folks who are liking this and the OCD are running into though.

-chris

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Post by dap9 »

Thanks minatour. I changed C6 from a .047 to a .01 and now it sounds exactly as I want it. BUT, if I let a note ring out for several seconds (longer than you'd hold a note FWIW), there's a point where the sweet OD sound sort of peters out and a less gritty note lingers. It's not a huge difference, but noticable. Does the value of R5 or R6 need to change to make up for this? :scratch:

Other than that issue, I find the pedal pretty pleasing. And the change in that cap really opens up the 'frequency' knob nicely. :applause:

Oh, anyone got a source on JRC386D ICs in the US? Can't find 'em at Mouser or Small Bear Thanks
minatour87 wrote:for the mids and highs questions...

first thoughts,,, check the caps to ground... any larger value than what is called out would reduce the highs...

second thought.. looking at the data sheet for the LM386, check what is connected from pin 1 to pin 7, The data sheet has an example of a cap/resister between these pins puts a bass boost for the amp...PP800 clone calls out nothing connected to pin 7...

last thought.... there is a lot of variables to getting to that TONE. it is hard to hear what you are listening to for a reference....or what you are trying to sound like...

Up date on the Value Jr: just finished learning Sweet Leaf ... nice tone ...my hand is sore... to answer questions off topic, it is a dean custom through a krank distortion to the Value Jr. with mods....pretty close to Sabbath's tone...
peace minatour87

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Post by minatour87 »

try a NJM386BD from mouser (p/n 513-NJM386BD) as a sub, it is very close to the LM386

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Post by minatour87 »

sweet OD sound sort of peters out and a less gritty note lingers.

some thoughts,,,, a weak battery or the gain is to high therefore turn up the guitar volume and turn down the clone...
as for R5 or R6 change, this has to do with more of frequency response then gain... it seems your question is more on gain/volume

a comment on your bass response is high with this pedal, i would have to agree, a PP800 and the PP clone boost the lows. My Dean Custom is all metal and this pedal makes it even more heavy compare to the TS808 clone with the same setup. This pedal would wake up some hot rod strats out there... and some mess-n-with to get it right for the Les Paul types....
as soon as a tune my razorback, i guess i am going to piss the wife off....
peace minatour87

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Post by dap9 »

Thanks man. It's not the battery - I just tried it out using a one spot and the pattery clip adaptor thingy. I thought that since I have a 5k pot for the gain that you were right, but even w/ the pot all the way down I still get the petering out thing. Turning the pot too high up creates a squeal, but there definitely is a sweet spot.

Would diodes cause any issues? I didn' have Schottky's so I have som 914s in there. It's on the breadboard so it's fun tweaking it.

Thanks for anymore help!

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Post by Fuzzer »

Well, 914's eat like .5 more volts than the schottkys.
The Freestompboxes Forum search function is soo great, use the search function..., the S E A R C H function.

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