Beedster

Agree 100%, no need to replace the unit, noise is there but minor, so check all other options first. As @sandy_r says could be as simple as mechanical (positioning) or excessive gain. If you're anything like me, the main problem is that once you've heard something you don;t like it gets progressively louder

That's a proper reply! Ears are good, but a waveforms is about as good as it gets 👍

Hi @sandy_r, looking at sopme of your posts (the Realist for example), I'm not sure how this forum manages without you! Many thanks, I'll check this out when I get the M-Pulse back later this week 👍

Lovely, good work 👍

Thanks Chris, agreed re costly mistake. I pretty much built the bass about 10 years back so it's easy for me to install a longer tail wire, I also have a longer tail piece that might help further. Longer tailwire and tailpiece - and therefore shorter distance between tailpiece and bridge - will affect tone, what's your thinking on the likely difference? Thanks for your help. Chris

Thanks folks, good advice. They're a Eudoxa 3/4 set. When I bought them I was under the impression that like many Pirastro strings, 3/4 strings generally served 4/4 instruments (and IIRC Caswell's didn't offer a 4/4 option). I bought them for a 3/4 instrument that on reflection soon afterwards was working very well with the Evahs I'd experimented with. I suspect the 4/4 will sing with them but not 100% convinced IO should risk it hence the thread

Following this with interest, I’ve an old bass in similar condition that I’m looking at restoring 👍

Thanks Jack, the silks on the strings on there at present start pretty much at the tuner itself so quite a difference in length. I think I may have to suck it and see......

It’s there

Defo something (static) on there, have you checked cables etc and perhaps tried another instrument into the same pre-amp?

I have a very long 4/4 DB and a rather nice set of strings I'm dying to use on it, but they are about a centimetre too short at the nut, that is the silks on the D and A strings run around 1cm across the nut. I've had this same situation on electric bass before and it made very little difference, but I have three questions re doing it on DB 1. Apart from the open strings (which I rarely play anyway) will this adversely affect tone/sustain on fingered notes on those two strings 2. Might I run into problems associated with too short a winding on the tuning peg? 3. Is there any chance I could damage the strings? Thanks in advance folks Chris

Many thanks @agedhorse, I hope so! While you're here, as I mentioned above @Steve Browning was kind enough to send me - and at no cost - a foot-switch for an M-Pulse 600. Sadly the pin number of the cable differed to that on the rear of the amp itself so I was unable to use it. Is there a workaround for this or is it simply a case of that foot-switch will not work with that model of the M-Pulse? Chris

Thanks @sandy_r, luckily I have a rather substantial collection of pre-amp (and power) tubes here so will have some fun experimenting. I'll update once done 👍

That really made me smile Greg, so while it may not solve this particular problem, it still helped I'm generally pretty good with these things so even if not the tube there's a 50/50 chance I'll get it sorted, if not there's a nice guy down the road who exerts magical powers over amplification. In both our cases powerful fiorces appear to be ensuring that we keep hold of our respective Mesa gear

Great help above all thank you so much, I’ll update once I’ve run the tests, swaps etc 👍

Agreed Russ, I’ll sort the fix, looks pretty straight forward 👍

Thanks @spyder that’s much appreciated and helpful. I’ve a lot of tubes here that will be my first port of call for sure, Russ do you have any spares?

A fine observation Steve, I get the funny feeling that by the time it gets back to mine, like the Carbine, it will have resolved and we’ll never know what was going on. Upside, I will have a Mesa rig again (although Russ if we do resolve this in the meantime you can of course choose to retain ownership should you wish) 👍

Rabbit seeks solution to Mesa problem 😆

Nicely put mate and I agree 100%, as we said when we met, it felt like two old friends meeting up despite having never actually met in the first place 👍

Thanks for your help @sandy_r and @Downunderwonder. Quick answer to some of the above; as far as I know I haven't used monster cables, and despite @Steve Browning very very kindly sending me a Mesa footswitch a while back I was never able to use it as apparently there were two version of the M-Pulse (I meant to open a thread here asking whether the cables could be switched but for some reason never got around to it). I think examining toggle positions might be helpful if Russ has the time and patience to do so, if not I'll continue this once I've collected the rig 👍 I have a strong sense that something I was doing here has led to these problems with the two previously trouble-free units, although much like the final scene of Burn After Reading (which if you've not see you really should), I'm damned if I know what the hell it was 🤔 Thanks again folks 👍