basstone

An effective vaccine is going to be the only realistic game changer. News on that front seems to have gone quiet recently but there are a few options in major trials I believe. It's going to be a tough winter all round but fingers crossed for spring next year maybe?

As you already have the active circuit, why not try it out. As noted above the single pickup wire is a screened cable. It should not be too hard to figure it out as its mostly prewired anyway. You'll need a 4 pot control panel or relocate the jack to the side of the body maybe? I guess it mostly depends if you have the confidence to experiment yourself or know a good local tech.

Looks too severe for orange peel unless you sprayed on a really thick coat in one go. Maybe it's a paint reaction with the underlying finish. Sand it back until flat and spray again. Hopefully the first coat will act as a sealer and the finish will be OK. Many light coats generally produces the best results. Good luck.

If its purpose is to offset the Miller effect, it would be better going directly to ground but C3 is effectively a short circuit at all but very low frequencies so probably does not make any difference. It would be interesting to know if it makes any audible difference disconnecting it. It could also assist with HF stability if the circuit layout is not particularly good.

It could be a wiring fault. Most often the battery circuit is completed by inserting the jack plug. The exception to this is usually on an acoustic bass with a built in tuner. Often the tuner is switched on with a small push button independently of the jack and it's easy to leave it on - I've done it more than once on my Taylor bass! I suppose the logic is that you still want to be able to tune the bass to play acoustically? makes sense but is not bass player proof 🙂

Changing the bridge saddle material changes to tonal qualities of the sound so maybe worth experimenting with that. Even string balance does rely on good contact between the saddle and the pickup. Check that the saddle cavity is clean and the bottom of the saddle is smooth and flat. Better even pressure can also be achieved by chamfering the bottom edge of the saddle resulting in a smaller but higher pressure contact. It might also be worth swapping out just the pickup, they generally all have a mini jack connector for the preamp, so long as the thickness is similar it's a quick and easy job.

I'll be there all being well 🙂

The Mackie amp kit replaces the original DSP with analog circuitry, which although easier to modify is still not straightforward! Picking up a pre-crossover signal from the preamp should however be fairly straightforward, retaining the input and tone controls and hopefully at a suitable signal level to feed the main LF power amp then feed the existing passive crossover. Another possibility may be to feed the full bandwidth signal to both amps and split the passive crossover for the 2 inputs! I have no immediate plans to try any of this out as I'm already on the same Icepower route as this original project (based mainly on the fact it is already proven in several good bass amps - my own GK SB500 included). I just thought as I came across it, it could be interesting as potentially there is less work involved than developing a preamp and phase splitter required to drive the Icepower modules.

I suspected that would probably be the case. If I have time I could measure the actual crossover frequency response when I get the parts to repair the speaker. I can't find the schematic for this analog preamp and surface mount boards are tricky at best to modify but it could be possible to feed a full range signal to the LF amp and retain the passive crossover.

My own active BC12 cab project has also been stalled due to other priorities and my repair business is now starting to pick up again and one of the items brought in last week for repair was a Mackie TH-12A active speaker. Why is this of any interest or relevance? I found that the DSP input module had failed and being SMT and not repairable I my only realistic option was to buy a complete upgrade kit for £139 plus £6.99 postage. This kit includes all the electronics ready assembled including; balanced input board with level control, 3 way parametric equaliser with bypass switch, active crossover, input EMC filter, SMPSU and dual amp module with 300W class D LF amp and 50W HF amp. The PSU and power amp are mounted on an alloy heatsink/ mounting bracket and the preamp boards stack on 4 spacers. All Fairly lightweight and compact. It would just need an input panel and mounting inside the cab. I wonder how well the active crossover would match the BC12 design? An alternative would be to use just the LF 300W amp with full range input and use the existing passive crossover design. Here is the link to the supplier: https://sbsav.co.uk/shop/59588-mackie-thump-th-12a-digital-to-analog-rework-kit.html Any thoughts?

Mine should be the same assuming the Marshall combo is still for sale. Maybe even have the amp fitted in my BCv3 cab by then