caitlin

Cheers! I knew the magic bits in the bass were 'eq' but i hadn't really equated that to 'pre-amp' like making it louder. I'd assumed there was *some* kind of contract between the derrière end of a bass and the in hole of the amps, collectively, in terms of impedance and volt level but that's naivety in the extreme I think mostly I'm lacking space for a real speaker, so this is what I have to live with, at least for now. I'm wondering if I would *enjoy* a real amp head which I could DI for now but allow me to connect to a real cab if the need ever arose (deity forbid I actually try playing live ever ) I shall distract myself from GAS and get on with learning where all the notes are.

Now I want to build a wireless doodle that ALSO powers the bass through the socket, half the batteries half the failure modes.

pinching someone else's picture but i hope that's ok because they get their advert out of it: you can see that if you trace from the body of the jack, up to the volume pot chassis, the right side pin is grounded that goes into the pot and connects to one end of the resist. there's 'some distance of resist' before you reach the 'wiper' which is connected to the middle pin. you can then trace from the middle pin back down to the tip of the output jack... I think this is the resistance you're seeing. We're dealing with AC current, not DC and 'leaking to ground' is what all these systems do deliberately to attenuate whatever frequencies they want to act on.

in your second picture the top pin on the left hand pot (which is the one i think is the volume) is connected to the case of the pot (ground) so you're measuring from the middle pin (wiper) through the resist out of that upper pin and through the case. I *expect* that if you measure the value of that resistance and wiggle the pot, the value will change. Enjoy your weekend too.

I think not! Got a spare you could swap in? we may have it!

There are ways to test them but they're complicated and magic, mr carlson's lab on youtube goes into lots and lots of detail about 'how this stuff works' but you need a magic tester to test them properly and i don't even know anyone who has one of those. If you had a wiring diagram you could try bypassing parts of the circuit to narrow down where the broken bit is, perhaps? Here's something i don't know: can one connect a pickup directly to the output of the guitar? bypassing the volume and tone circuitry entirely, I can't think of any reason why not... that would allow us to see if we can get any life from it at all.

That some signal at all reaches the amp means that you *have* a signal path, but something is 'attenuating' it, which is what the variable resistors do anyway, the couple the signal to ground through some magic bits of tat. that the signal is not GONE means there isn't a hard short to ground, but something like the dielectric breaking down in a cap or in the jack socket MIGHT create a resistive path to ground. I'm new to this forum and I don't think anyone's twigged that I'm an idiot yet

Assuming this to be a daft question but since in debugging NO questions are daft... it's not the amp, is it? I trust it's been checked with other guitaren? Otherwise, the tuner doesn't have a microphone that could be hearing notes that way? is something shorted to ground?

This was actually the impetus I needed. Mine is now tidy again. Thanks!

I'm sorry. I'm sure this has been covered to death but my forum search skills are crap. I have all these bits plugged together and I don't know if I'm damaging anything or what I'm missing: I currently have an active bass plugged into a channel strip on a mixer with +4b of gain on the input and the channel strip at 0db, flat eq. The mixer bounces off to a samson servo 170 which is driving a pair of old surround sound system speakers which have two 4" drivers and a tweeter each, they're driven full range because I've just got one amp, although the tweeters can be disconnected. I do have an active DI box which has a balanced output which I can power with phantom power from the desk and I know there's something about impedance? but honestly I can't *hear* any difference with the DI in between the bass and the channel strip and with it out and it's a load more wires and crap to plug in. Would I be better off with one of those 'preamp' pedals to use as an amp sim, do they output the right kind of voltages and whatnot for the mixer? I know 'stompboxes' would be the same impedances as the guitar because they would be built to go in the instrument doodle on an amp. Halp?

Yeh, they seem to be 'consumables' in so far as they can bend. You've not explored 'microphones' with this drummist have you? I mean they're a revolution in 'being heard without breaking your stuff'

I'm transferring over from drum clef and it's pretty confusing mixing up C with a floor tom, and all my hi-hats are sounding like As. I've been playing from tab for ages and I've learned nothing except some robotic songs. Now I'm taking lessons I'm actually taping over the tab in my books to force me to get the music notation. I'm heading for understanding chord relationships because more than anything I want to be able to make stuff up, not just slavishly play what's on the page. I figure if i can read *other* musical parts (piano and that), I can then link up what I learn of bassing and make up stuff to match even if there isn't any bass music to copy or work off of.

I'm generally suspicious of vocalists who suddenly want to be percussionists, but yer clutch man has some nice muting going on there. The correct location for a cowbell is here: \/

My best friend nagged me to put it back together because I was whining about not having a bass to practise on. I've just been out to the garage, wafted a couple of bar past the holes in the cans, but not actually forced that pressure straight through them, I think that would lift metal out. I've washed a BUNCH of wd-40 through the pots and honestly, I can't remember which one felt gritty any more. The EQ responses seem heightened, but what's psychosomatic at this point? The treble one certainly gets a bit hissy at full up and I don't recall that from before. All the pots now travel full range without any scratchy sounds, so I'll leave it to sit for a while and find out if that's a fix that's going to hold or fade. Thanks for the shout about the oil, I didn't realise that was safe to shove in there. Now I have no justification for that 5, worst forum ever.

I don't believe many of these rooms are *Currently* as tidy as these photos, mine *certainly* is not. It looked like this shortly after painting it. It's got a few things on the walls and a lot more junk in it now. It's a really small room, I'm crammed into the corner with my phone over my head to make the picture, but it's MY room, MINE! You can just barely see my two tiny self built (from kits) tube amps, a 3W 2 tuber and a 5W 3 tuber. I love them, they scream.

I'm replying to myself a LOT here, but https://www.ebay.co.uk/itm/MINI-POTENTIOMETER-B100K-100K-16MM-LONG-SHAFT-WITH-CENTER-DETENT-ACTIVE-PICKUP/273651439128 looks roughly right, the pins are the wrong type, but if i cut the old ones off leaving the pins in the board i could trim these to fit and solder the stumps to the in place pins perhaps? the shaft lengths look within the ballpark anyway. Whatcha think?

Actually would blowing them out with compressed air possibly have any effect?

I've SMASHED the pots with switch cleaner and wiped them like a maniac and the fixing is only temporary When you say spray oil do you mean like WD40, I do have some quite posh transmission oil for 90s japanese engines, but that's getting a bit towards 10W-30 I'm not sure any amount of cleaning will save the one that feels crunchy, I fear the track is delaminating in there. I will try anything you suggest though, having nothing to lose. Also, SHUT UP, I'M MAKING UP REASONS TO GET THE 5 STRING, why are you stopping me?! 🙂

Yep, I've basically given up, I'm buying a 5 string on Friday (unless someone else gets to it first; I won't settle for a red one.) I'll resurrect this one if I stumble into any pots that will work, or possibly rework the cavity to use remote pots.

I think my two upsetting band splits were both due to 'stage fright' Any time it looked like were getting anywhere, shows booking up, venue sizes improving there would be a manufactured implosion one way or another to reduce us to square one and back to a hiatus and eventually a pub gig or three. I think they died in the gap between 'authenticity' and 'stage craft' so having not practised doing anything to fill a larger stage, panicking, locking up and standing very very still which isn't the best idea for rock music That and the drummer was the most annoying b*tch on the planet.

Ew, I realise suddenly that the pots are mounted *through* the pcb and so have the pins pointing in the opposite direction to every single pot I can so far find on the planet. Is this a *thing* and I lack search foo? I can see no evidence on the pots of the pins having been bent this way, but just possibly they were straight pins at some time that were mangled into place. I just can't find any 'the same'. Such learning, so inability

Cool, I'll see what I can scare up from the internet then. I've got a bit further in than I intended and won't be playing for a few days, oops. The wiring is a mess, unsure whether to leave well alone or to try and make it a bit nicer.

Haha, I have NO excuse commenting on this, but from my just about zero experience with amps, I'd guess at leaky caps, or a dodgy ground. You can poke in them with one hand and a wooden stick to see if noises change, but they'll kill you if you lick the wrong bit. Probably safest to give it to someone who has an isolation transformer and can diagnose it safely. Is it a 50Hz hum, or does it vary in any way, like the angle between the amp and the microwave? My home built amp was fuzzy till I poked a wire with the wooden chopstick and found the dry solder joint. Right I'll leave that guess there till someone with *actual* electrical knowledge comes along.

If you could, that would be reassuring! Thanks. Thanks for the link, itu. I didn't realise the A and B were the log/lin designation. Smells like they're all 100K and just the taper varies. It's irritating that the screen printing on them is so weak. It would be nicer to have replacement pots inhand before taking the bass to bits so it's a fast changeover.