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Everything posted by Mr.Grumpy

  1. Cliff notes: The second guitar pedal ever made was a circuit clone of the first pedal ever made. When was it? About 10 or 15 years ago, it was a big deal in the "effects community" (i.e, this place) because it was gradually becoming apparent that many "boutique" pedals were straight up copies or slight modifications of mass-produced pedal designs. And so started an informal project by the effects community to reverse-engineer boutique pedals and reveal their secrets. Boutique builders did NOT LIKE THIS EXPOSURE, and some threatened legal action against platform where this damaging, infringing media (like electronic schematics of effects pedal) was for a time, prohibited here at HC. You also weren't allowed to link to, nor EVEN MENTION what came to be known as the "forbidden forum" (freestompboxes.org) because they were a 'rogue' forum where you could see for yourself that the Fulltone FullDrive is tweaked version of the Ibanez tubescreamer. Somehow, the boutique pedal business has survived and thrived. There's more pedals for more companies - big and small - than ever before. The thread about the first Tonebenders sent me on an internet search, as I don't think I had ever seen a schematic for the "MK I" tonebender. Well, it turns out that the second guitar pedal ever made (Tonebender Mk 1) was a tweaked copy of the first (Maestro FZ-1). The "designer" tweaked the design by running the circuit at a higher voltage, and presumably had to adjust resistor values to match the higher voltage and different transistors used. But it's a direct copy of the FZ-1 circuit, and I find it surprising that Maestro/Gibson didn't do more to protect their intellectual property, as the device was patented and it would have been easy to show that the circuit had been copied.
  2. The difference between this type of power supply and the OneSpot daisy chain is the 'tiny box' power supplies do have individually regulated outputs, albeit with a common ground. That should help in those situations where some pedals seem to put noise on the power supply chain, usually high-current draw digital pedals. OneSpot is a switching regulator, I'm guessing these tiny box units use linear voltage regulators.
  3. Props to EHX for not using the misleading and over used phrase "isolated outputs". The EHX unit is a daisy chain in-a-box, and they say so. Nothing wrong with that as long as you know what you're paying for, and most pedal boards don't need a true isolated ground power supply. Isolated outputs is not the same as isolated ground.
  4. I finally found a schematic for the Mk I Tonebender and was surprised to find it's a xerox COPY of the Maestro FZ-1, exact same circuit design with different transistors and component specs. It also operates at 9 volts versus 1.5 or 3 volts of the original Maestro Fuzz-tones. So, the "attack" control in fact controls the biasing of Q2, which leads to the 'gating' of the signal. I suspect that the "good" tonebenders are those where the transistor gains were closest to the designer's original. That's the problem, those old germanium transistors, crummy by today's standards, are a big part of why those old fuzzes sound the way they do.
  5. Sometimes, dumb luck works in one's favor. I repaired a "vintage" (early 70s) Acoustic 170 (?), a HUUUGE solid state combo amp with a single 15" driver in a "horn loaded" cab. I used it as a bass amp, then found out it's more of a 'general purpose' amp for keyboard or PA use. When I bought it, it made sound, but the volume was extremely low. Opened it up, and there were a couple of bulged electrolytic caps, I replaced them, and the amp worked perfectly. I wish I hadn't sold the damn thing, it was cool. Electrolytic caps aren't just used in the power supply.
  6. There's some COOOOL non-guitar stuff towards the back of the auction, it's not just guitars and small, high-end combo amps. There's quite a few effects pedals, most sorted into lots by manufacturer, including a Gold Horsey Klon and some other 'rare birds' like a Mu-Tron Bi-phase. A couple of keyboards, including a Rhodes piano and Hohner Clavinet. Several racks of effects, and what appears to me to be some seriously high-end tube (valve) hi-fi amplifiers and systems.
  7. From reading Ibanez' description, that's almost certainly what's normally called a "treble bleed" or "treble bypass" on a volume control. Like the ad copy says, it keeps the highs intact when the volume is turned down. Here's some links to read more: https://www.fender.com/articles/tech-talk/how-a-treble-bleed-circuit-can-affect-your-tone https://www.premierguitar.com/articles/28387-mod-garage-deep-diving-into-treble-bleed-networks Looks like the cap values listed in the links above are 1,000 pF or 1,200 pF, and often with a resistor in series or parallel (or both) with the cap.
  8. That thing is not really a guitar amp in the conventional sense. It's a powered PA speaker, apparently with extra circuitry to emulate the 'voicing' of a regular guitar cab. NO, the "Mic no mo" will NOT work with this "amp"... It requires a guitar amp that has a speaker jack that's accessible, most open-back guitar combos have this. If you're wanting to record silently, the best way is probably to use a high-quality modeling unit plugged direct into your recording interface, then listen over headphones.
  9. The "Mic no mo" is a special type of direct box, specifically meant to be used with a guitar amplifier. It has a circuit that electronically emulates the frequency response of the speaker cabinet and microphone. Since it does not have a line or instrument level input, it HAS to be used with an instrument (guitar) amplifier. And if that amplifier is a tube amp, you still need to have a speaker connected with a speaker cable and not a standard instrument cable. There are some direct boxes that can handle a speaker-level signal, but most don't have cabinet emulation.
  10. There are several "Bass preamp and D.I." pedals on the market designed for recording or PA use. The Tech21 SansAmp Bass D.I. (about $200) is the industry standard and widely used. There's also a cheaper, chinese-made work-a-like unit made by the "B" company ($30). What do they do? They electronically simulate the frequency response of the amp/speaker cab/microphone signal chain. Tech21 makes several versions of their bass DI units, and Eden, Ampeg, Behringer (shhh!) and others make similar units as well. The last couple of home recordings I've made with bass guitar I've just used my bass amp's (Ampeg PF-500) D.I. output, I prefer it to the sound of my "B" unit that I own.
  11. Just thought I'd throw out something a little different from the plethora of "how's my singing?" threads. My wife's a high school English teacher, and a couple of times I've recorded audiobooks or excerpts of books for her class. I'm assuming this is permitted under 'fair use' copyright interpretation because these recordings are used for EDUCATION. I don't receive any compensation. This weekend I'm reading excerpts from The Scarlet Letter; it takes place during colonial times and the language used is archaic and flowery. Stuff like this: Whew! And that's not even a whole paragraph. Thankfully, I'm just reading excerpts and not the whole book, the language and vocabulary is challenging even for me. Most of the prose is narration by the author, but there is some dialogue and that means I have to change my voice to show the reader it's a person talking and not the narrator, so "voice acting" is needed too. My vocal booth is a walk-in bedroom closet that's been acoustically treated with my homemade bass traps, studio foam and recycled couch cushions. I have a large diaphragm condenser mic, a Rode NT-1 and use a Mackie Big Knob recording interface. I use a desktop PC running 64-bit Windows 7 and edit the audio is edited in either Reaper or Audacity. I can post pictures tomorrow if there's any interest.
  12. I own a gizmo similar to this, a "Violet Ray" electro-something thingy. I still worked last time I tried it, although the power cord to the unit is getting cracked and sketchy. Thanks for sharing your medical fetishes with us, Corny. Years ago, my parents would drag me to "used book fairs" and one of the random items I got was an early 70s catalog of medical supplies and instruments. This was fascinating stuff for a 12 year old! Yes, they had rectal dialators, very similar to the ones pictured earlier in this thread. They had skull saws. And they had a Keigel exerciser thingy, a unit that had a hollow but fluid filled "bulb" that was inserted into a woman va-jay-jay...there was a length of small tubing attached to a pressure gauge. I guess a woman is supposed to use this after childbirth to get her coochy tightened back up? The really great part is the thing had a medical cutaway illustration of the device in use.
  13. Traded my Squier Stagemaster for a S-U-B Axis, and now I regret it. The 'licensed by' Floyd trem on my Squier was pretty solid and reliable as I recall. The locking trem on the S-U-B seems to be a lot more finicky, and I've broken strings a few times. And the overall build quality and wood quality seems to be lacking in the S-U-B.
  14. My first guitar was a Gibson Sonex. Sort of a Les Paul shaped bolt-neck with a plastic ("reso-phonic") body. I hated the thing and ended up trading it in for a Squier S-3 Bullet, one of the early American-made ones.
  15. I'm pretty sure it uses a multi-layer PCB. It doesn't show up well in the photo, but there's charring of the PCB substrate (presumably epoxy-impregnated fiberglass) so that bits of it are carbonized - which act as extra random resistors in the circuit as the amp warms up. At first it was just hissing, which I could tolerate, but now it's making loud popping and crackling sounds. I'm going to email the local tech today (he's Mesa's authorized repair guy locally) , see what the fee is going to be and figure out when I can afford to get it fixed. I've already bought a replacement amp for band practice, a solid state Marshall combo, because volume is more important than tone. * edit * I emailed the amp tech, sent him the same photos posted in this thread. He replied in a couple of hours, and said my amp is in "pretty good condition" and that "I can fix your amp." So he's pretty confident it's repairable. I may have to wait until October to drop it off, that whole paycheck-to-paycheck thing.
  16. I emailed Mesa, and unfortunately they are not able to replace the board (they're not made anymore), but they think it might be possible to repair the board. They told me to call & discuss... I have this weird thing where I don't really like to make phone calls, but I got through, and guy at the Mesa factory was very helpful. One of their authorized repair centers was very highly recommended by Mesa's tech, so I'll probably take it to that guy after calling or emailing him and getting the details. I'd like to avoid the whole disassembly, packing and shipping business if I can.
  17. Call me maybe? Why? America was on a path to 'metrication' - conversion of our units from Imperial to the metric system, in the 1970s. We learned about the metric system in school, over and over. It really is easier and much more sensible than the random weirdness of the Imperial measurement system, with its weird units and a counting system. One unit - the ounce - is used both as a unit of fluid volume and as a unit of weight (1/16 of a pound!). The reason America still uses Imperial measurements is because of President Ronald Reagan. It's because Republicans are anti-intellectual and anti-science. Still, I believe most American cars are now made with metric fasteners, but I wouldn't be surprised if smaller industries (like effects pedals) are still using imperial tooling and fasteners. http://themetricmaven.com/?p=5820
  18. They're probably English ('Imperial') sized, fractional inch. Probably hard to find those in the Phillipines. *edit* I just checked with my calculator, 7/64" (a common smaller size of hex/allen screws) and it works out to 2.77 mm.
  19. I just stumbled across this during a web search, a very interesting article (to me, LOL) about this amp. http://www.math.uwaterloo.ca/~rblander/music/studio22.html
  20. I can't figure out how to put the pics where I want them, or insert text between the photos. But here they are. The close up picture of the component side shows the charred part of the circuit board by the diode and R131 resistor pads. The picture of the solder side of the circuit board shows some browning around the power tube sockets, but I think the real problem is where the large cap and power resistor are. Interesting that the cap is a large value but rated for low voltage, only 16 volts. I think that's the power supply for the LDRs that do the normal gain/boosted gain switching inside the amp. The power resistor mounted under the circuit board may be a repair or re-work, I'm not sure.
  21. I opened it up and took a good look inside. It's not as 'toasted' as I thought it was, and although there's "browning" around the tube sockets the worst of the burning is right under a power resistor. It looks like a 2-watt carbon comp type resistor, mounted on the underside of the board. From reading on some amp forum somewhere, it appears this is common and well known occurrence with these amps. I'm sure this is a grid supply that has to be at a particular voltage. My music man amp has something similar - half wave rectifier, a filter cap, and dropping resistor and zener diode. Anytime the amp is on, that resistor probably gets close (or above) 200 degrees F. pictures later...
  22. Yes, Mesa's "estimated repair chart" shows typical repairs for a Studio .22 to be "$150 - $200" and if that would restore my amp to working condition that price would be a bargain. But if you scroll down on Mesa's repair page, it has a separate entry for "Badly burnt PC board damage" says "need photos for est." Heck, it would be worth another $400 if Mesa could install a new, fresh board. I know electronic stuff doesn't last forever, but we've been spoiled by tweed and silverface Fenders that - of course with maintenance - keep going for 50, 60, 70 years.
  23. I've gotten a good few years from this used amplifier. I've owned it about 9 or 10 years, I think I paid $400 for it back then. It works fine for a few minutes, then after it warms up for a while, it starts hissing and then later, gets this crackling and rumbling noise through the speaker that eventually overwhelms the guitar. NO, it's not an intermittent effects loop normalling jack; I already have a patch cable on the effects loop. I pulled the chassis out years ago to take a look, and the PC board looks like burnt toast. Good ol' board mounted tube sockets. Sure, they're fine until the warranty runs out, and maybe even a few years beyond that. I was reading some amp & electronics forums and although it sounds like a temporary fix MAY be possible, it's due to an ongoing deterioration issue that can't be stopped while using the amp. One forum's advice was to find the burned, carbonized spot on the PC board and scrape it off, as it acts like an extra resistor between random circuit traces. The only real long term fix would be to transfer all the existing components to a shiny new circuit board, probably not cost effective for Mesa to do, and probably not for me either. Years ago I saw a foreign, maybe Russian website that was selling "clone" PCBs for many popular tubes amps including Marshall, Fenders and Mesas. Can't find anything now, Mesa seems to do a pretty good job keeping their IP (schematics 'n' such) off the internet. I may slide the chassis out, take a few pics, and ask for a quote from Mesa, just for laughs. But most likely it's bound for the trash heap, the dustbin, garbage dump, landfill....I don't really see any 'rehab' possible that doesn't cost as much or more as just buying another tube amp. I've already got a used SS Marshall from GeeSee picked out, now I have to explain this to the wife.
  24. This popped up in my FB feed, haven't watched the video yet, but this seems relevant to this forum. https://www.sweetwater.com/insync/guinness-world-records-pedalboard/
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