sandy_r

[TL; DR] ...salient posts collated at the beginning of this thread

[TL; DR]... Salient posts now collated at beginning of thread

Feel free, Paul, that's what they're there for Now that i've made a CNC PCB version, my vero prototype for the JFET circuit is available if you'ld like it (you said your Sinsonido is the version without built-in DC and 2.5mm headphone jacks?). The JFET circuit provides output mixed from both bridge mics (as opposed to only 1 on the Aria), has better Tone variation, and 2-3 times longer battery life than the original Aria board - but no headphone drive direct from the jack socket. You'ld have to replace the pots with a slightly smaller size, or slightly enlarge the cut-outs like i did let me know if you want this - no cost, feed it forward

right! hah - you could try DIY, like an article around the time they first appeared: Make yer own ES headphones ...can you imagine? Layers of polarised plastic with highly-charged conductive strips wrapped around them nestling snugly against your ears - i think i'd rather swim with piranhas!

yes ...pretty sure the speakers were bigger and flatter tho'! 😉

Quad amps ..."Wire - with gain"!

Actually it dates back to early wireless (er, radio) days, i believe - when the 'Tone' function was usually limited to a single control (if any)

Figure 1 shows the single-adjustment tone control which provides a symmetric EQ response that is flat at the center of the adjustment range Figure 1. Single-adjustment tone control for Bass Moving the control in one direction simultaneously boosts the bass and cuts the treble until about 5.5 dB of boost and 23 dB of cut are obtained. Moving the control in the other direction boosts the treble and cuts the bass in an identical fashion. Figure 2 shows the typical curves obtained from approx 5 Hz to 20 kHz with a 340Hz centre frequency, for the lower half and upper half of the control range, respectively Figure 2. The tone-control circuit delivers good response characteristics in both the lower half (a) and upper half (b) of the control range Insertion loss (at centre) approaches 6 dB. Since this is a passive circuit, all component values can be scaled, if required, without affecting the AC transfer-function.(Keep the source impedance low and the load impedance high. In this application the source is <10k ohm, and the load > 400k ohm) The audio clips posted above were recorded at the EQ flat, Max Bass and Max Treble positions

Hi Paul (and welcome to Bass Chat!) In common with many circuits in equipment 15 or more years old, Sinsinido preamp PCBs are also starting to need attention, due to ageing of the electrolytic capacitors. Symptoms of the failing caps can vary between inoperative controls, oscillation, loss of signal and heavy current drain from the battery Early attempts to replace PCBs from Aria have been somewhat successful, but over the last 10 years or more even this level of support appears to have dwindled Several BCers have been able to make good progress with repair/replacement with different approaches: @lemmywinks replaced the Aria electret bridge-mics with a piezo element and standard preamp PCB; @Richard R initiated & led a successful team effort (whilst on the SoS forum) to reverse-engineer an Aria PCB, identify the issue and repair the unit; i've been able replicate Richard's work as well as successfully creating a hybrid pcb loosely-based on the Aria design, and in addition just create a new circuit based on a single JFET preamp/tone stage All these different approaches have successfully overcome the component-ageing issues of Sinsonido PCBs - none are commercial enterprises, however, so if you prefer, or need, to obtain a drop-in PCB rather than DIY you'd have to arrange for someone with the relevant skillset and tools to use the designs posted here and build (or mod?) a PCB for you Until recently i've been able to do some practical work on these preamps, with a view to assisting other Sinsonido owners here, but recent health issues have started to refocus my priorities Apologies - probably not the answer you'd hoped for (...nor the grammar, up with which one is prepared to put, eh @Dad3353 ? 😉 )

A big shout out to @rwillett, for kindly donating some 3D-printed pickup plates for my DIY bass to set off my rather funky attempt at a cover over my homespun windings - it looks the biz now. Many thanks, Rob! (...plans inhand to feed-forward the kindness)

Whatever the requirement, the answer is always a Fender Rumble - just change the number following, to suit the budget, so in your case that would be a F R 100

Wow - what were the others like?!? What to say about a schematic which: takes pain to state the circuit is 'positive' ground - but then shows both transistors as types which would require 'negative' ground (NPN type); doesn't show any bias voltage arrangement for the 1st transistor (unless - it's really a PNP type... in which case they have the collector & emitter connections drawn incorrectly) ...but apart from that - we can trust the remainder of this circuit absolutely, yes? Good ol' Uncle Ernie! PS. if that foil is uninsulated, it might be an idea to check it can't make contact with any component leads on the PCB (...and if you ever get any hum or other elec type noise, more shielding wouldn't go amiss 😉)

What a geezer - leave the door open, Steve...

Okaaaaaay - so let's see if i can summarize... for some reason, best known to him and his cat, he likes to scallop the edges of fingerboards (**might be related); when he obtained the bass, the finish on the top horn was present and correct (in one photo), but whilst scalloping the fingerboard at the 12th fret, his concentration slipped ...and so did his rotary file/sander; he fitted a new (longer) neck, and didn't take into account total string-length and possible neck-dive**; so now he has to fit a bridge which overhangs the rear of the body - he desperately loses some forward weight, by chopping the headstock in half, horizontally - and in the process has to cut the corner off a tuner plate (see rear headstock), so it will all fit on the new 'skinny' head; but all this still hasn't solved the neck-dive, so he has to extend out the top strap button by an inch I believe this approach is known among Luthiers as 'Lateral Thinking' - ie. wide of the mark

Sorry ....Ziiiiiiiip!