DMB Lunar Echo

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

So, anyone ever take one of these to bits? As I understand it, it's based on the DM-2. We all know about adding an LFO to a DM-2, and about shorting the delay resistor to get the runaway repeats. If the DM-2 assumption is correct, that gets us most of the way there.

One of the two things that are intriguing to me is the "wrecked" position of the tape switch, which DMB claims is like "modulation gone crazy" and compares it to someone tweaking the delay knob. I'm guessing this is something along the lines of shorting or adding resistors to increase the depth of the modulation to pitch shifting degrees.

The other is the lo-fi/hi-fi switch, which seems to be just changing the RC filter on the repeats to darken/brighten the tone on the repeats.

Thoughts? Pics?

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iefes
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Post by iefes »

If anybody is still interested in this I have some gutshots for you. Maybe it helps :) Hope everything needed can be seen on the pictures. It was hard to pull all the wires apart without breaking something.

On my Lunar Echo the glued pcb was already loose when I got it brand new (!). So I was able to take some pics. I can see two V3205 IC's and a selfmade vactrol.

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stevo83
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Post by stevo83 »

That thing is a mess :shock:

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iefes
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Post by iefes »

unfortunately yes. But it sounds very sweet :mrgreen:

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daimondamps
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Post by daimondamps »

iefes - why don you take a shot of the bottom side of the pcb's??!!!!!! :shock:

"The V3205SD is a 4096-stage low-noise, low-voltage BBD analog delay line"

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rs
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Post by rs »

Isn't that a GGG AD-3208 pcb?

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fakcior
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Post by fakcior »

Yes, it is. Plus modulation add-on.

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iefes
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Post by iefes »

daimondamps wrote:iefes - why don you take a shot of the bottom side of the pcb's??!!!!!! :shock:
Hmm... I'd have to remove this rubber foam but it's glued onto the pcb. I want to sell this pedal at the moment and don't want to pull it apart to much. Sry! :(

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iefes
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Post by iefes »

Here is a pic of the bottom side of the modulation-board. Maybe this helps somebody figure out what the modulation is doing exactly :)

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