Lovepedal - Les Lius  [traced]

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
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WhiteKeyHole
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Post by WhiteKeyHole »

Voltage (controlled) variable resistor.

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Coma
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Post by Coma »

still....IMO it's a horrible sounding pedal. Didn't give me anything.

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WhiteKeyHole
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Post by WhiteKeyHole »

ibodog2 wrote:So the boost function is a 1k pot switched in to be parallel to the 330R resistor?
Yes, basically.
ibodog2 wrote:What's a good substitute for the BAV99 part?
Pair of 1N4001, 1N914, etc.

Also, the "collector-to-base" resistor is 3M3 in the Les Lius, as opposed to 2M2 in the Woodrow.

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WhiteKeyHole
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Post by WhiteKeyHole »

Volume is 100K. Your diode configuration is incorrect. The "boost" potentiometer at full (least resistance) should provide a near short to ground and that, at least, should have some effect. I don't think you wired it correctly.

You might want to change the name of your layout as it is not representative of what is going on in an actual Les Lius.

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cbriere
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Post by cbriere »

sugg. for name= LESS LIUS .... :applause:
i would like to see an correct schem. of this.

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WhiteKeyHole
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Post by WhiteKeyHole »

ibodog2 wrote: For the boost I followed your direction in an earlier post that puts the pot in parallel with the existing 330R/47uf combo. If I change the boost switch so that it is either 1K pot or 330R/47uf then there is a difference switching between them. However the difference is not like the actual pedal where the knob is controlling a boost. The knob is actually diminishing the gain. The 330R/47uf combo seems to have about the same actual gain as the pot set to least resistance. On the actual Les Lius when you kick on the boost there is an increase in distortion even with the boost pot set to minimum.
Which corresponds with my direction as, with the boost on, the maximum resistance becomes ~ 250R.

Is your bypass capacitor faulty?

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WhiteKeyHole
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Post by WhiteKeyHole »

It looks like there is a 1K resistor in parallel with the potentiometer, too. Regardless, at its minimum resistance I'd expect there to be some concrete change versus 330R. It could be that what I've described is actually in series with the 47uF capacitor, hard to say. Try it out.

I'll draw a schematic.

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WhiteKeyHole
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Post by WhiteKeyHole »

Image

Don't ask about the diode switching, just how it's done. Being that the switch is not attached to the enclosure, it could be done like this for some kind of reliability.

"ALT. TO FET" will probably pop.

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Post by WhiteKeyHole »

Should be correct. The 47uF bypass capacitor covers the trace so I can't be sure where it's going, but I don't actually see its cathode connected to the ground plane or a via. As it is now, I can't see any other possibilities. If the OP could remove that capacitor, we could know for sure.

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Post by WhiteKeyHole »

Image

Bloop. Little closer to the original switching, but still simplified. Just an option for people wanting to go the FET route.

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Post by MoonWatcher »

Slightly off topic, but who makes those SPST momentary footswitches?

I want to take a whack at relay switching. It's been long overdue, and I just haven't bothered to source that part.

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Post by MoonWatcher »

Thanks, WKH. I know that SB carries them, but I'm really interested in who actually makes them. I source stuff from all over the place, and SB is typically slow getting orders down to me.

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Post by teemuk »

If you’re going to build this thing, you can make it more “cost-effective” than the original design easily:
Diode D1 can be omitted since either D3 or D5 bypasses it anyway in any state of the following DPDT switch. Furthermore, one of the Schottky diodes with the polarity of D3/D5 is always connected so you can eliminate another one of these and replace the DPDT switch with a simple SPST switch that just enables or disables diode D4.

Also, the whole FET switching thing with some kind of IC needing a regulator and bunch of other stuff seems rather pointless for such a simple function it is performing. Just replace it with a simple switch. If you worry about switch popping you can just parallel that switch with an e.g. 5-10 Meg resistor that is permanently grounded. That should keep the other end of the emitter bypass cap always in a 0 VDC potential, having the switch effect only at AC.

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Post by WhiteKeyHole »

Yes, it can be simplified to a SPDT for the diode switch. As I said, I presume a DPDT is used to offer some reliability in lieu of a mechanical connection to the enclosure. D3 or D5 do not bypass D1 in all states of the switch as, as notated on the schematic, the switch is ON-OFF-ON.

Yes, again as stated, the second schematic is posted as an option to use the (still simplified) convoluted FET method. The first shows a SPST switch as an "ALT. TO FET." A large resistor should be put in parallel with the switch, as you said.

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Post by teemuk »

Ok, I must have missed that detail because I was simply looking at the schematic. In that case, I guess it doesn't work without the Si diodes and a DPDT switch ...but you can still omit one of those Schotkky diodes, though. :wink:
Image

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Post by candletears7 »

hi guys, just curious as to whether a working vero or perf layout has been created? I will try to get this on the breadboard, but a working layout done by someone more adept than I would be great. :D

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Post by modman »

candletears7 wrote:hi guys, just curious as to whether a working vero or perf layout has been created? I will try to get this on the breadboard, but a working layout done by someone more adept than I would be great. :D
viewtopic.php?p=77020#p77020
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Post by candletears7 »

Thanks Modman, I had seen that of course, but there seems to be some contention as to whether that vero or the boost section in particular is 100% accurate to the Les Luis circuit. Or it may be that I need to read the thread more thoroughly! :wink:

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Post by WhiteKeyHole »

I'd just drop the FET switching scheme, posted more as a novelty. If you must use it, try whatever FETs you have on hand that fit the pin-out you've used (DGS). Capacitor value isn't very important, how about 10pF. The switch is not momentary. C5 is 47uF.

Don't know what you're asking about the diodes.

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