sandy_r

Step 1: Get a new band, mate! ...

'anti-crush protection' for cables/connectors in the speakon panel? (so you can't jam the cab back against a wall, etc)

...indeed - but not S to the OP, apparently 😉

Re. the zoom SD card no show - could be the computer OS throwing a hissy fit that the SD filing system is 'not recognised'. I get that with Widnose sometimes, determined to reformat all 'foreign' filing systems. Also watch out for popup windows giving options about how to interface with the card/USB as a new folder Are you able to connect the recorder to the computer via USB cable, rather than load the SD card direct? I use that as my preferred transfer method now, on my Zoom H2 Re. access to back of PJB C4 cab - it could be that all access is expected via the front, after build completion (removing drivers, of course). Fun!

Here's a comparison of an audio clip from your mic recording, with a clip from a direct recording of my YamahaBBN4 passive - 0.1s of the low E from each. Your recording showing predominantly fundamental with some 2nd harmonic; the Yamaha (no treble cut) showing the same plus some higher harmonics No obvious indication of overdrive (eg signal breakup due to clipping) on the PBJ C4 recording PJB C4, mic recording: Yamaha passive, direct recording: A test of your TC head & bass with a C4 (and also a similar config cab, diff brand?) at GAK looks like the way to go

The first recording looks fine - clean signal, good dynamic range If no visible, or other obvious sign of something rattling in the cab, it's still possible that there is intermodulation between the direct sound from the back of the speaker cones and resonating/reflected sound from the back of the cab, for particular frequencies (eg. around the B and E open-strings) Since 2 slightly different frequencies (from source & cab resonances) can cause separate 'beat' frequencies which will include the sum and difference of those 2 frequencies - the sum will sound like a harmonic and the difference will probably be outside the normal hearing bandwidth and just be perceived as vibration TL;DR - the sound could just be caused by cab resonance - but do the easy tests first to eliminate other possible sources (eg amp, bass, etc) good luck! ...if you do visit GAK, give my regards to Gardener St (many fond busking memories) 😉

BTW is the recording direct or mic? If direct, then we're only hearing half the story

Why not take your bass & amp to GAK first? Ask to try them into a similar PJB cab and a similar cab from a different make. Easier 1st journey, and if all sounds ok then focus on your cab if however you hear a similar sound on your 1st visit you know its down to the amp (and/or the bass?) ...and you've saved a journey lugging the cab across to the North Laines!

hmmm doesn't sound like a rattle to me - more like an intermodulation on certain notes that would suggest earlier in the chain than the cab something like that could just happen in active onboard circuitry, but my guess is its happening in the amp

...i think you mean: digital speedboat 😉

(OP has preamp, just needs line level interface)

hi you may be looking for something similar to this: 2×active pickups, VVT, 3-way selecting P1, P2 or both, stereo jack switching power on/off If you're certain that your bass was originally Vol, Bal, Tone you should be able to adapt this circuit (ie. change 1 Vol into a Bal) Use a wire-colour scheme which is different to the pickup wire colours, to avoid confusion (for you and 'helpers') when trying to decode the wiring If you added the (non-standard) 'kill-switch', then you have a choice: remove it, change it into the pickup selector shown here, or leave it as an extra power switch. Your call NB. If your wiring cavities are fully shielded (and grounded) just use the relevant pot (& jack shield) lugs as ground connections - soldering the pot cases just wastes solder, increases probability of dry joints and can cause heat damage to those soldered parts good luck

...agreed, re. checking jack seating with external nut/collar removed - still little scope for correction

...the jack sockets are all soldered to the PCB, so there won't be any relative re-positioning Could move the whole board** towards input sockets by reducing the bushing, but then output socket(?) would need extra gap (**assuming other controls have some leeway)

hi don't know if this will help... i've found that very occasionally the shape/position of the recess round the jack tip on some leads means that the dip in the springy socket connection aligns with the recess on the jack tip in such a way as to make for intermittent connection (ie slightly pushing or pulling the jack in the socket can make contact, but the slightest nudge and its no go) my long term solution (where feasible) was to change out the socket to a different brand, but i've certainly used the careful tweaking of the offending connection strip using 'snipe-nosed' pliers to add a slight downward 'V' profile to that strip (handy being the end one!). Need to watch out for affecting any switching action at that lug - and not tweak it so much that other leads jam and twist the connection good luck!

...my sons and grand-daughters expect nothing less!... 😉

No boring P or J for me (yawn!) So i'm going to choose their Grandpappy - the Tutmarc ...which was still on the scene (just) when i was born

I can't comment on that brand, but i'd echo others' comments about 'snagging' on those clips (which are probably removable, but then - no soldering clips!) When my own venerable iron finally died, a few years ago, and i no longer had access to the work one, i got the following 60W temp-controlled iron (supplied with a variety of tips) and just got an adjustable soldering frame - all decent quality and good functionality, i've been very pleased with it (i see it's reduced to £39 in the Black Friday Sale, and the frame is £14 - both from Am*zon) 60W Preciva temp-controlled soldering station Burntek soldering frame

Yes, no worries - only to be considered for out-of-warranty, or a definite keeper. Thanks for the audio clip, it appears to be the usual suspects of a mix of mains-related, 2nd-harmonic (100Hz & multiples) and higher data-related noise (could be local, or broadband data-packets) - presumably transmitted as modulation of radio-length frequencies and then detected by the semiconductor devices in the preamp. Too much info, i know! Hopefully the active bass loaner will show the way ahead

...yeah, but you're not listening in 4D!

hah - me too - but as with fixing damp in a single room building, you need to know if the water is coming thro' the roof, floor or walls! key points from your own tests so far: - the noise also happens when you use an amp (+ the guitar) near, but not connected, to the computer; - with guitar into Presonus into computer, the noise only significant when switching guitar into active mode This info tells us that the noise is being transmitted, it's being picked up in the guitar, and it's not a ground-loop type issue So, in addition to ensuring well-grounded and fully-enclosing shielding in the bass wiring cavities (and if so, don't bother initially with trying to ground pot cases, if they aren't already), it could also be helpful to add some simple resistor/cap filtering** at the input of the active pre in the bass (ie. between pickup(s) and their preamp wires - this would be the time to slip on a small ferrite bead over the wire from pickup, too) ** experiment with values, but try, say, a 5 kOhm resistor in series between each pickup 'hot' wire and its connection to active pre, and a 1n (1000pF) ceramic capacitor from the active pre end of the 5k, other end of 1n cap to ground (ferrite bead over pickup lead end of the 5k res - bead can be glued if you fix the noise issue) NB. Increasing values of Res and/or Cap will improve filter action but eventually start to reduce the pickup signal all the best!

Kudos for 'Take Dad' and 'Bo Daddley' ...they'll be making an appearance in my spoof Cracker Jokes this year - thanks DrJ !

(feel eminently overqualified, but here goes...) Handbags and Grandads

hi David Let's kick the word 'static' into touch ...unless you're prone to receiving small stinging discharges of electricity with an accompanying blue or white flash Computers are very noisy creatures, unfortunately, and not usually well-designed to 'play nice' with analogue equipment ...Welcome to the world of ElectroMagnetic Interference (EMI)! EMI can happen: by transmission (ie. without any connecting wires), by conduction (thro' connecting wires), and by induction (the magnetic interaction of nearby wires, usually coiled) More likely to be a problem where low-level analogue signals are passing thro' either high-impedance circuits (found in parts of passive guitar wiring) or thro' high-amplification circuitry (eg active guitar circuitry in general) As a simplification, EMI can be reduced by conductive shielding (usually around low-level signals needing amplification), or magnetic 'shielding' (eg. ferrite cores around wires carrying higher-frequency signals) So for instance, it's a good idea, especially in the presence of digital noise EMI 'generators'/'transmitters' such as computers, to increase the effectiveness of any existing shielding in guitar signal paths: - ensure pickup/control wiring and cavities are completely enclosed by well-grounded conductive surfaces, all grounded back to a single point (usually the guitar jack shield lug); - experiment by adding ferrite rings, looping any wires connecting guitar to computer, and low-voltage power supply leads thro a ferrite core a few times, to see if this reduces EMI transmission by the digital/swiitching devices - if you, or friends are handy with elec. tech., try fitting some small ferrite bead/capacitor filters on input paths of low-level analogue signals Bit of a dark art for us mere mortals, unfortunately -good luck!

This schematic appears to show 25K linear - if correct, then available from various sources (eB*y, Rev*rb, Mous*r, Digik*y, NorthWestGuit*rs, etc)