Just finished this up. 1590b , top jacks, microprocessor relay bypass, KD522B Russian Diodes , BC549 transistors. Sounds great.
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Any DIY pedal builders on TB? Strut your stuff!
- Thread starter SubHuman
- Start date
hmmm.
came across this mod for the ehx mole,
by a guy name moosapotamus, he removes the biasing resistor and says "Switching it out gives the bass boost a slightly brighter "punchy," sort of compressed, fuzzy tone"
looks iffy to me, biasing is now different
calculated for Vce, got negative, not sure what to think of that
try ltspice, the circuit works like a switch instead.
I havent tried this irl yet.
Makes sense i guess, it is "compressed" to between 0 and 9, fuzzy cos square wave, i don't know about brighter. This just seems. not ideal.
came across this mod for the ehx mole,
by a guy name moosapotamus, he removes the biasing resistor and says "Switching it out gives the bass boost a slightly brighter "punchy," sort of compressed, fuzzy tone"
looks iffy to me, biasing is now different
calculated for Vce, got negative, not sure what to think of that
try ltspice, the circuit works like a switch instead.
I havent tried this irl yet.
Makes sense i guess, it is "compressed" to between 0 and 9, fuzzy cos square wave, i don't know about brighter. This just seems. not ideal.
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The Tachi is the result of many months of experimentation, forged by the desire for a better BASS overdrive. It can provide anything from clean and transparent preamplification, treble-boost EQ, or a high-mid focused overdrive that retains dynamics and clarity for your most aggressive tones, all with lots of output on tap to drive your amp or next pedal (try it into a green big-muff)! It’s dual-band, high-voltage design preserves the dynamics and clarity of the fundamental range (lows and low-mids), while allowing for the harmonic range (upper-mids) to be emphasized and/or overdriven independently with reduced intermodulation (non-harmonic) distortion. Furthermore, the bandwidth is limited via high and low-pass filtering for tight bass and controlled high frequencies. An external 36V unit reduces any power supply interference and allows the pair of hi-fidelity OPA2134 amplifiers to operate with a maximum of headroom and performance.
Controls:
"Drive" controls the input sensitivity. Use to adjust your overall sound (clean vs overdriven), and to compensate for instruments of varying output levels.
"Blade" controls both gain & shape of the harmonic band, ranging from flat/wide/clean/dynamic to boosted/narrow/compressed/driven. Located before the clipping circuit, it functions either as a high-mid EQ or a distortion control, depending on the “Drive” setting.
“Power” controls the output level. There is lots of it!
RECOMMENDED SETUP Procedure:
Starting with Blade set to 0, raise Drive until just before you hear distortion. Then, increase Blade as desired for an overdriven sound. Note that increasing Drive raises the fundamental frequencies along with increased clipping/compression of the highs, thus shifting the balance toward the lows. Setting Drive lower can restore more of the treble and cutting power achieved by Blade.
SPECIFICATIONS:
Input impedance: 330k Ohms
Output impedance: 6.67k Ohms
Power Supply: 36V DC, 100mA minimum, 2.1mm Center-Positive connection
It is the hog's foot. Not sure about the history.
Anyway, here's my double mole, on each stage are 2 100nF lift switches, 1 moosapotamus mod switch, 1 switch to add a 22nF for a less aggressive high cut.
Painted with nail polish~
That's really unique! Is that fish cast resin or 3D printed? How did you mount the dip switches?
3D printed. The DIP switch was mounted on perfboard and the rectangular hole i cut was a very tight fit.
A few globs of hot glue and it's not going anywhere.
oh yea i forgot, highly recommend special glue sticks used for electronic potting.
i think it's polyamide based. tacky as hell and sticks really hard, but you need a higher power gun.
my office uses some cheap chinese ones but they're just as good, more sputtery because they werent kept in a dry environment.
i think it's polyamide based. tacky as hell and sticks really hard, but you need a higher power gun.
my office uses some cheap chinese ones but they're just as good, more sputtery because they werent kept in a dry environment.
Exactly the same circuit except that the tube has been replaced with JFETs:
Passinwind
I know nothing.
- Dec 3, 2003
- 23,079
- 46,050
- Disclosures
- Designer/Toaster Tech @ Passinwind Electronics
Nothing some of us haven't seen before, but a contributor to my open source preamp project is using JLCPCB to provide very inexpensive fiberglass fascia plates:
Since his version already uses a PCB from JLC it makes for a pretty convenient printed graphics solution, although since everything else is sourced from Tayda he also could've just had them do a direct UV print.
Since his version already uses a PCB from JLC it makes for a pretty convenient printed graphics solution, although since everything else is sourced from Tayda he also could've just had them do a direct UV print.
I'm playing with a new enclosure design right now.
Mesa Boogie Bass 400 Preamplifier:
Passinwind
I know nothing.
- Dec 3, 2003
- 23,079
- 46,050
- Disclosures
- Designer/Toaster Tech @ Passinwind Electronics
Love it, and I enjoyed having a look at your linked content too.
- Feb 16, 2008
- 21,240
- 23,638
- Disclosures
- John K Custom Basses
Yup! The costs of buying aluminium cases was adding up
