rmorris

[quote name='largo' timestamp='1478268021' post='3168048'] When I was packing up the gear after last gig, I noticed the wire on the power supply to my HA400 headphone amp was starting to split. Stupidly, it's been left in the trailer with the rest of the gear and so I'm not sure what to buy as a replacement. Could anyone point me in the right direction? Worst case, I buy a whole new HA400 unit as they're not that expensive, but fingers crossed & thanks for your help Basschat buddies. [/quote] Not sure what you mean by "starting to split" but if it's still working maybe just fixing it with insulating tape would be okay ?

[quote name='Jonotron' timestamp='1477954656' post='3165576'] Sorry to be late to the party! I think it's the Bakelite fingerboard that's the problem. It reacts to temperature at a different speed to wood therefore the neck acts like a bimetallic strip- it's an inherently unstable design hence the lack of truss rod cover. Shame really as it's a great sounding bass but getting a decent setup is nigh on impossible [/quote] Bakelite ? I Googled the model number and everything I read says it's ebony ???

[quote name='redbandit599' timestamp='1476651187' post='3156055'] Yes, the amp has transformers, it's not class D. [/quote] I meant does it have audio transformer/s in the signal path ? As opposed to the normal mains power transformer. I think the transformer issue prob a red herring any way ???

Yeah - need to know the model to judge whether worth the likely repair cost.

[quote name='redbandit599' timestamp='1476371322' post='3153740'] Hi all Now - I know that the received wisdom is that dirt and fuzz should go between bass and amp, and if you use your amps effects loop then it's usually for modulation type stuff. But, try as I might - I just think that my dirt pedals sound much better in the loop of my EBS HD350. I have the loop set to parallel so it maintains a 50% clean mix at all times and it just sounds more of a complete sound to me. Just has bit more quality to it than when the drives are in front. I'm running a Tech 21 VT and a Cog Tarkin in there at the moment (along with a TC Corona, a Boss EQ, a Mooer Tender Octaver, a Digitech BSW and a basic switch to bypass the lot.) The difference between signal strength doesn't seem to have any impact on any of my pedals - and they are all silent and powered from one Onespot and a daisy chain. Obviously, all good and I buy the 'if it sounds good to you, then it is good' approach - but I just wonder if I'm listening wrong as I seem to have a lot of bad practice in there! Am I the only one!? Cheers! Jason [/quote] Makes sense to me that the loop with a 50% mix might sound better than pedals before the input. Loss of low end etc etc... Unless you are using a 'fuzzface' type pedal that relies on a highish impedance (ie passive pickup) source for its sound. As for the output transformer possible issue mentioned - does the EBS HD350 (sorry don't know the amp) have transformer(s) and I don't see the issue even if it does (am prepared to be corrected) ??? Bass Regards....

[quote name='HowieBass' timestamp='1475222674' post='3144064'] I reckon the preamp in the Thunder is also the same as that in my Spectrum LX - as another BCer mentioned you can get a great sound by keeping the passive tone set fully open and then add some bass boost with the active. Flicking between the coil tap options on mine (the dual tone toggle) also changes the sound in a useful way in both passive and active modes. Have fun with it! [/quote] +1 on the series/parallel switch. I had to change my pickup because it went microphonic. But I recall that switching to parallel was useful to avoid 'mud' when playing chords.

[quote name='HowieBass' timestamp='1475152496' post='3143486'] Grangur's already replaced the IC so it won't be that... maybe it is just a dry joint at the output pin! [/quote] OK. I thought he had just refitted the existing if but maybe I just missed it in the thread.

[quote name='Grangur' timestamp='1475100092' post='3143145'] That's sound. BUt I have just found a dry-joint on a resister. It's on the feed to pin 1 on the IC. Pin 1 is the output A [/quote] Def sounds like that might be the problem. Was just going to suggest reflowing all the solder joints - can't always see a 'cold' joint - and/or replacing the ic with a new one. Resistors can fail as well so not necessarily a capacitor problem even if it is a faulty component.

[quote name='HowieBass' timestamp='1475059356' post='3142658'] This was actually my point! Would the low voltages (9v and 18v) be likely to age the capacitors in the preamp? [/quote] The voltages shouldn't be a problem. Really just random failures over time.

[quote name='Grangur' timestamp='1475012076' post='3142378'] They're all red drop cap type. Most have values on them. There are some really small ones on there though. I guess the values of those probably wont to too critical though. It's not like it would blow up. [/quote] OK. I used to have one of these but have emgs in the bass now. If you can get hold of a multimeter that does capacitance you should be able to measure the value. It may not be exact but should be accurate enough to indicate the standard value used.

[quote name='HowieBass' timestamp='1475013895' post='3142386'] Do non-electrolytic (ceramic?) capacitors dry out? [/quote] They can't dry out as they aren't 'wet' to start unlike electrolytics. They can still go faulty though but electrolytics are much more likely to show problems especially after 10+ years.

[quote name='Grangur' timestamp='1474897746' post='3141327'] Many thanks. You could well be right. I guess though, if the caps in mine have dried, than most other pre's from Thunders can't be far behind. In an ideal world I would know the values of the caps and buy new, but we don't live in an ideal world. [/quote] Any electrolytic caps on there ? If so replace those first. Value should be written on the case.

From the initial posting: [quote name='Harryburke14' timestamp='1471460039' post='3113235'] I have lately been noticing myself getting small electric shocks from the strings and bridge of 2 of my basses (Sire M3 and Harley Benton Jazz bass). They usually occur when I've been plugged into the amp for about 20 minutes and in both inputs on the amp. The amp itself is Ashdown Vintage 12 for those interested. Does anyone know what would be causing this, and if so how to stop it? [/quote] So to clarify was this happening 'on its own' or was the iPhone/Charger involved at this stage ?

Do you need more current than your current supply can provide ?

[quote name='horrorshowbass' timestamp='1471293799' post='3111965'] Hi guys, I've managed to lose the battery cavity cover for my yamaha rbx 775, any suggestions for a makeshift/direct replacement? Thanks Michael [/quote] I think I'd cut a piece to suit out of thin wood or plastic / acrylic and fix it with screws - either small woodscrews straight into the bass or fitting threaded inserts into the bass and fixing with M3 machine screws. Allow screws to be countersink to keep the surface flush. Threaded inserts better for removal / refit when changing batteries.

[quote name='dood' timestamp='1470509803' post='3106504'] If your on board electronics are all EMG, maybe this a go: [url="http://pages.ebay.com/link/?nav=item.view&alt=web&id=191917878998&globalID=EBAY-GB"]http://pages.ebay.co...lobalID=EBAY-GB[/url] EMG electronics will happily take 27v, so this 24v mod could be just the ticket! [/quote] And I was just going to suggest investigating different physical battery sizes - such as lithium type batteries that might usually be used for photographic eqpt etc...

The pickups will, electronically speaking, load each other and alter the sound. To get a true mix of the pickups 'real' tone you need an active mixing circuit or individual outputs to an external mixer.

[quote name='Beer of the Bass' timestamp='1468707095' post='3092855'] Components in parallel will reduce the resistance reading across the pickup, but never increase it. So while measuring a pickup coil in circuit will under-read slightly, a 256k reading almost certainly indicates an open coil. I suspect the meter will be seeing the 250k resistance of the pot, and the coil would measure open if tested out of circuit. Depending where the break is, it may be possible for the repairer to just unwind a couple of turns and re-solder rather than doing a full re-wind. [/quote] +1 the lower resistance measurement is reasonable. The 256K reading indicates a basically open circuit pickup with the reading being basically the attached pots. Anyway it's the problem. Confirm by removing pickup and measure in isolation.

[quote name='MoonBassAlpha' timestamp='1468675315' post='3092569'] Nothing to worry about. Loads of older design amps do this. I think it's just the power supply capacitors discharging a bit asymmetrically. Many modern designs have a relay that disconnects the speaker before the power supply is removed, hence no thump. [/quote] +1 yep - cap discharge thing. Can be a bit disconcerting if it gets to FOH 😣 If an issue new and poss tighter tolerance PSU caps may help to some degree. As stated many designs avoid it by anti thump circuits at turn on and turn off.

Hi. I am finally getting and old CMI EBO type bass making some noise again after some maintenance / changes. I'm missing one machine head bushing / ferrule (missing when I got the bass years ago). I've measured one of the others and the relevant dimensions are: Tuning Post Diameter : 10mm Bushing Inner Diameter :10.5mm Bushing Outer Diameter (excluding knurled bit): 12.18mm Bushing Outer Diameter (including knurled bit): 12.45mm Bush Length : 9.17mm Bushing Diameter across top (ie the bit you can see when fitted) : 16.03mm Headstock thickness is approx 16mm so bushing length isn't critical and neither is the Diameter across the top. It's a press fit type hence the 'knurled bit' - I can't recall a more technical term but I expect there is one :-) splines ? So the thing is I can't find a replacement anywhere. Anyone have any ideas or (long shot !) something same / similar hanging around ? I might be able to do something with 12mm metal tube with a 1mm wall thickness so 10mm inner diameter - would need to be taken out a touch - and building up the headstock hole a little with , say, 'Superglue' to get a good fit for the 12mm tube. It's a lot of hassle for one bushing... Thanks for reading.

[quote name='4stringslow' timestamp='1468482860' post='3091161'] Is the tone control on the bass really that important in these days of amps with multi-band tone controls? Why roll off anything within the bass when it can be done within the amp, and with a great deal more control? [/quote] +1 I used to have a fretless Westone Thunder which did benefit from knocking off treble clank but apart from that little use of passive tone knob.

Are you noticing any difference between open strings and fretted notes ?

[quote name='fretmeister' timestamp='1468422012' post='3090832'] For £30 the box models will just be a daisy chain in the box. They won't have isolated outputs. Can be fine if your pedals aren't noisy though. [/quote] Yes. The descriptions can be 'tricky' (as in misleading) as sometimes a supply is described by the seller as 'isolated'. But often the outputs aren't isolated in the proper sense of being galvanically isolated from each other. But the outputs may have individual short circuit / overload protection ie if one output is short circuited or overloaded that output will drop but the others remain okay. For good noise immunity you need proper isolation.