BOD2

I've heard about this problem before - often on 5-string basses. Sometimes changing the string is enough to resolve the problem. The other thing you can look at is the break angle over the nut - where the string goes from the nut to the machine head. For best results the break angle should be as steep as possible as this exerts more pressure on the nut. To do this ensure that the string is wound around the post such that it leaves the post as low down as possible - some fiddling around and care when winding the string on to the post can help with this.

I don't know how helpful the block diagrams will be, but here you go.... [attachment=71015:V_Amp1.jpg] [attachment=71017:V_Amp2.jpg]

Are you using the 3-way switch as a pickup selector ? If so, what kind of switch is it ? Is it a "Fender-style" blade switch (as fitted to a Strat) or something else ?

Is this the part ? [url="http://www.guitarpartsworldwide.com/Gotoh+Double+18V+Battery+Box+PU1ETjBBRE14b0RkalZIWnZKSGM"]http://www.guitarpartsworldwide.com/Gotoh+...b0RkalZIWnZKSGM[/url] [url="http://www.wdmusic.co.uk/product/18v_Double_Battery_Box_With_Screws_BB-04W"]http://www.wdmusic.co.uk/product/18v_Doubl...h_Screws_BB-04W[/url]

If the pickup winding has broken somewhere then you would get an "open circuit" reading and no signal from the pickup. It's worth checking that the wire hasn't broken where it leaves the bobbin. If you examine the pickup there will be two blobs of solder where the hookup wires join the bobbin. The pickup winding should also be attached to these blobs of solder and should be visible (just) as two very fine wires coming from the pickup. Sometimes the pickup winding breaks here, disconnecting it from the hookup wires. If you can see a stray "hair" of pickup winding here that's not soldered to the blob then you could repair it simply by resoldering at this point. The DC resistance is a measure of the number of windings on the pickup. More windings = higher DC resistance. Higher output pickups will often have more windings, although it's not quite as simple as that. The Wizard 84s (at 11kOhms) are probably heavily overwound, as opposed to the Wizard 64s which are a more vintage style of pickup. These two pickups probably sound quite different.

As with all aftermarket add-ons (pickups, machine heads, bridges etc. etc.) the marketing people will always make a compelling case for why their piece of kit will make your bass sound better. But there's actually very little real "science" to support any of these claims. Provided the kit is well made from good materials then it will likely sound "good". But whether or not it will make your bass sound the way you want it to - well only you, the player, can be the judge of that. Lots of people swear by BadAss bridges. So you can be confident that they're good and well made. But lots of vintage basses also sound fantastic with the old standard bridge. There are also lots of other bridges out there that are every bit as good as the BadAss. So yes - Babicz bridge may well sound every bit as good, or better than a BadAss on your bass. Unfortunately you cannot tell until you try it. I would hope that the sticky about BadAss bridges here doesn't make it sound as if a BadAss is the only bridge. It's just that lots of people ask about them, which is why the sticky was written. There's plenty of room out there for any well made bridge.

Have you checked through the "sticky" thread ? [url="http://basschat.co.uk/index.php?showtopic=194"]Grounding Issues[/url] Most of the common causes/cures are mentioned there.

It depends if there are already any shims in the neck pocket. If it was shimmed already then that might have raised the action and also the saddle height to compensate. Adjusting shims is a bit hit and miss. I would only do this if you're confident about removing the neck etc. and remember that you'll have to adjust the action again after any shimming. If the action is acceptable then I'd be inclined to adjust the pickup upwards, as endorka suggested. But to answer your original question - yes, shimming the headstock end of the neck pocket with a narrow shim would lower the action at the bridge end.

Have you changed where you actually place the amp on the stage recently ? Or has the stage layout forced you to position the amp in a corner, or near a back wall in the gigs where it's sounded louder ? (as opposed to being nearer the middle of the stage away from any walls). Positioning a speaker cab in relation to surrounding walls can create a "coupling" effect that can affect the volume.

[quote name='phil.i.stein' post='1027766' date='Nov 18 2010, 11:28 AM']some interesting info here, particularly regarding mics. [url="http://www.alectrosystems.com/tips/audio_tips/audio_tip_RFI.htm"]http://www.alectrosystems.com/tips/audio_t...dio_tip_RFI.htm[/url][/quote] That's a good step-by-step guide to indentifying the problem. Except the last part where it suggests disconnecting the AC ground to break a "ground loop". Don't ever do this. You might kill someone !

There's one big problem with this whole "vintage guitars sound better because nitro lets the wood breathe and modern poly doesn't" argument. It's called Fullerplast. [url="http://www.caraguitars.com/fullerplast.asp"]http://www.caraguitars.com/fullerplast.asp[/url] Basically, all your vintage Fenders from around 1963 onwards were sprayed with a 2-part catalyzed coating to seal the wood prior to finishing with nitro cellulose lacquer. There wouldn't be much "breathing" going on through that stuff ! Also, wood doesn't breathe. It's dead - it stopped "breathing" when they chopped the tree down. Some guitars just sound better than others for all sorts of reasons. The finish of the guitar is just one small factor among many.

First you need to do a quick check of "other" possible problems - 1. Is the bass guitar ok (if it's active, do the batteries need replaced) ? 2. Is the guitar lead ok ? 3. Is the speaker cab ok ? 4. Is the speaker cable ok ? If possible, check each of those items with a different amplifier. Think what was different to when you tried it at the seller's house. If you still have distortion when you've ruled all of these out, then it could be the amp - but check these first.

I'm not quite clear about how you've wired the selector switch - you say you've taken the earth side of each output to the switch ? If so, then that might be the problem. All the earths should be "common" and all connect to the same point, which is ultimately the earth side of the output jack. What you need to switch is the "hot" wires from each neck's output and connect these via a 3-position switch to the hot side of the output jack.

Yes - that seems like a reasonable assumption. You've got a 50/50 chance of getting it right !

Something doesn't sound right. If you had to wait until it "warmed up" then it would be fitted with a Standby switch to allow for this. The "warm up" thing generally onlty applies to amps with valves in the power section and not the preamp. I would contact Marshall and ask them the question.

There's general informatio about Hiwatt here - [url="http://hiwatt.org/"]http://hiwatt.org/[/url] Not much specifically about bass amps, though.

[quote name='webby' post='992084' date='Oct 18 2010, 11:48 AM']Nice one, thanks. Rehearsal tonight so I might leave it til tomorrow. Edit: Just had a quick look. Looks like the current pickup has one red and one black wire, while the new one has one red and one white. I'll match up the red wire assuming that's the 'hot' one, yeah? Edit 2: Ah, according to Kent Armstrong's Schematic PDF, the white wire is the hot one! [url="http://www.kentarmstrong.com/KA_Wiring_Instructions.pdf"]http://www.kentarmstrong.com/KA_Wiring_Instructions.pdf[/url] It looks like the wires from the current pickup just go to the selector switch. I just wire the new one exactly the same yeah?[/quote] That's what I meant about there being no "standard" colour coding for wiring ! But at least you've got the information you need. Yes - you just wire the new pickup exactly the same as the old one. To answer your original question about volume and tone pots - the existing ones should be fine. There's no reason to change them unless there was a problem with how they worked.

It should be just a case of desoldering the old pickup and soldering in the new one. The only possible issue when mixing pickups from different manufacturers is that it's not always clear which pickup wire is the "hot" and which is the "ground" (they often use different colours on the wires). On a single pickup bass this is not an issue - either will be ok. On a dual pickup bass have a look at the wires on the new pickup and solder it the way that looks most obvious. Once in place, connect it all up and listen to the sound you get when BOTH pickups are on. If it sounds a little "thin" then you've wired the new pickup "out of phase" with the old one - all you then need do is open it up and swap the wires of the new pickup around and all will be ok.

[quote name='mr.sibs' post='981731' date='Oct 8 2010, 04:21 PM']Thanks, silly question, but what setting should I use on the multimeter? The Diode setting? Help very much appreciated [/quote] That's not a silly question. But the answer depends on your multimeter. Some have a "continuity test" setting with a beeper that will make a noise when you touch the two probes together. If you don't have that then use the "resistance" setting - set to the lowest range. On this setting, when you touch the two probes together you should get a reading of zero. When checking your earth connections you should be looking for a reading of zero (or very nearly zero) between the earth connection of the jack and any earthed point, since what you are measuring is essentially just the resistance of a piece of wire between these two points.

I'm surprised no one has mentioned Shergold Modulators in this discussion. [url="http://www.shergold.co.uk/index.html"]http://www.shergold.co.uk/index.html[/url] Guitars and basses with swappable FX "modules" from the 70s.

Use your multi-meter to check the earth continuity. Attach one probe to the earth side of the jack socket and then touch the other probe at various parts of the controls that should be earthed. Check the pot shells all have good earthing. In particular check that the bridge itself has a good earth connection - one probe on the bridge and the other on the earth of the jack socket. If the pot shells aren't earthed then run a wire from a good earth point to one pot shell then daisy-chain a wire to each other pot shell. The foil screen should earth all the pots together but sometimes the foil breaks. If the bridge isn't well earthed then unscrew the bridge and inspect the wire that comes up through the body. Splay the ends of this wire and rub the underside of the bridge with a sandpaper to remove any oxide layer to give a good connection. A little vaseline (has to be vaseline as this is conductive) on the underside of the bridge where the wire touched can sometimes help. But always use the multimeter to check your connections are good.

Re. the pickup problem. Are you saying that when BOTH pickups are on at the same time they can sound a bit weak but that each pickup is ok on its own ? If so, then it could be that the pickups are out of phase with each other. To fix this, reverse the hot and ground wire of ONE of the pickups (it doesn't matter which one).

You might find this thread useful - [url="http://basschat.co.uk/index.php?showtopic=50774&hl=bridge+measure"]http://basschat.co.uk/index.php?showtopic=...=bridge+measure[/url]

The SQs are good solid basses. I've owned a P-Bass for years now and it's a real workhorse. Lovely neck. Information about the SQ series here - [url="http://www.21frets.com/squier_jv/thesqpage.htm"]http://www.21frets.com/squier_jv/thesqpage.htm[/url]

The neck pocket is going to be the problem. A 5-string neck is wider all the way down and quite significantly wider at the body join which would mean it won't fit the neck pocket of a 4-string body. Then the 4-string pickup isn't wide enough to cover the 5-strings either.... plus you'd need a new bridge.