caitlin

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?

On 08/10/2019 at 20:59, ahpook said:

You folks are so....tidy !

 

 

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?

1 minute ago, jacko said:

Yes. 

Our drummer has three cowbells and has broken the mounts on all of them hitting them so hard.

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:                         \/

How many of us have madamps?

I'm sad this is no longer available as a kit, I have a G2 and a G3 which are both stunning amps for generating overdrivenness at sensible volumes, in the bathroom with an sm57 in their face they sound great recorded.

You have done a scarily nice job of the wiring! Quite puts mine to shame, this is before it was finished like, but even so it's a tip.

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?! 🙂

1 minute ago, itu said:

There's another issue: those pots have long shafts. May take some time to find similar.

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.

20 minutes ago, BassBunny said:

You're spot on with what you have said so far. The bass and treble in the centre "notched" position is flat, no boost or cut. Similarly the balance in the centre position has both pickups equally blended. 

If it is the blend pot that's faulty, you've already identified it as a 100K linear and they are easy to get hold of. The pre-amp looks identical to one from a bass I have. I'll have a look and report back if you need the values of the bass/treble pots.

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.

I have what I believe to be terminal crackle.

A solid blast of switch cleaner in the back of the pot and some wiggling clears it up for a time but the death rattle returns in hours.

The balance pot is a wee bit crunchy

This bass has what I believe is a PJ arrangement, split neck size pups and a bar pup near the bridge.

It doesn't work without a battery so I surmise it's 100% active.

Inside the back looks like this:

and pulling off the knobs reveals some nuts:

So I think if I get those undone and the jack out of the way the board should come out.

The volume pot is labelled A100K

The balance (I believe ) is labelled B100K and is center notched.

The bass and treble pots are also center notched (I guess because that's to mark when it's neither boosting or cutting) but the labels are mostly worn I think one says B100K and the other one *probably* says 100K but there's no trace of an A or a B.

I'm more than confident soldering, I've build point to point and strip board tube amplifiers which actually work and haven't cause a fire, but I've not got a lot of confidence identifying these pots.

I have a multimeter so I guess I could pull them and measure the range and rate (I don't know if they're linear or log) but I wonder if anyone might know what this arrangement looks like.

Any advice would be greatly appreciated, I'm just learning what these knobs DO and now when I turn them I get sad.

1 minute ago, SpondonBassed said:

Welcome Caitlin.

Regarding your crackly pots, there is a sub-forum where you can locate fellow members who may be in a position to help:

BCers Prepared to Help Fix a Bass

In that sub-section, Repairs and Technical, there are other useful areas to explore.  Happy hunting!

Thanks, I'll have a rummage in there. I've tried blasting them through the holes in the back of the pots with switch cleaner and wiping the pots from end to end and that gets them working flawlessly for a time, except one which feels a touch *gritty* so I think the track on that one is truly spent

It would be much easier to tear into if I got that other bass, because I'm dependent on this one working to play it.

Nah, I have a healthy shame for me and my silly drumming friends. I do like the one about checking if the stage is level thoughbut.

Here's me at the 100 club in yer london.

I promise to *mostly* talk about bass though.

Hello.

I'm afraid I'm a drummer, I've been doing that for decades and a long time ago I thought learning a bit of bass might help my band's rhythm section stuff work a bit better. I have no idea if it did or not because I'm not playing with a band, haha.

I mainly play a Roland TD-30KV at the moment, but I have my Gretch Maple Renown tubs packed up ready for the next time I get to be really loud.

Anyway, that's not what we're here for. I've now had TWO bass lessons and can nearly name the notes inside the stave on the bass clef without sweating. (I'm avoiding tab and trying to learn some theory)
I'm playing a JHS 'Vintage' 4 string at the moment. It's a bit sad really and has crackly pots. That wouldn't usually be a problem for me to fix, but it's an active bass and they're soldered directly to a board in the cavity which I think is glued in!

I'm trying to talk myself into AND out of buying a Cort Action 5 string but don't know where that will end up yet.

For better or worse I've started recording myself to hear how bad it sounds and HOPEFULLY to hear some improvement over time. I don't know if I can post what I've got because it's using Trinity backing tracks off their grade 1 exam stuff.

So yeh, hi!