billybigbass

Taken it out, selling on, putting the old passive circuit back in. Thanks for the assistance but for all I'm doing playing wise short term passive is fine.

28 minutes ago, BassBunny said:

Can we backtrack a bit.

What pre-amp are you using? Is it installed in the bass? Have you tested it without any pickups/blend/ volume control?

It looks like an orangey/red wire that is the input to the pre-amp, touching that with bass plugged in should give you a low buzz.

All I have is in this kit, that includes a preamp, does it not? 

https://www.gear4music.com/Guitar-and-Bass/Wilkinson-Active-Bass-EQ-System/36DF?origin=product-ads&gclid=Cj0KCQjwiqWHBhD2ARIsAPCDzamGlw2VAZVK4nn_ChOd19XcHWYqjPSAOsyl3eaCuOYh_-oC4YBQNUEaAgKEEALw_wcB

57 minutes ago, Woodinblack said:

Well, thats ok, although if you have another pickup (unless it is the same type wired the same) it will be out of phase..

I was confused as you showed that Warman pickup diagram, which show that green and red were one side, which you shorted together and black and white were the other phase which were also shorted, whereas the other diagram seems to show kent armstrong which have different wiring. So what pickups are they? I assume not those warman.

Have you buzzed out and made sure there is a connection between white and (one of green or red) and then (one of green or red) and black?

Also you should be able to buzz out between the Red output and the earth on that bass and have a value with the knob fully towards that pickup which is 1 / (1/(resistance of pot) + 1/(total resistance of your pickup))

The pups I have are the Kent Armstrong HB5E3B model.

This diagram below is about all i can find for the kent armstrong bass pickup wire colours online and seems correct, their guitar humbucker pickups are different just to confuse.

Have hit up Flynn amps in glasgow who are good at this type of thing, see if they'll help. Losing the will to live, this is my 2nd day dicking about with it. 

Might be the jack is wrong, I had to take the jack socket off the new harness as it was the wrong type, mine has a long barrel jack, just wondering if I've done that re-wiring wrong now.

with a voltmeter and the 9v battery plugged in I get  near to 9v reading at teh jack terminal for battery wire, I dont however get any voltage reading on the hot terminal that the volume pot is wired to with my amp on and lead plugged in the bass. my logic tells me I should get a voltage reading there. I get voltage readings off the bass and treble pots but not the volume or blend pots. I do get resistance readings off the volume and blend pots though. Not sure of any of that is significant.

Electronics is a bit like double dutch to me, if there isn't a clear wiring diagram to follow I'm struggling.

57 minutes ago, Woodinblack said:

 

appreciate black is usually earth but there is a separate bare earth wire with these pups, 5 wires in total.

the way the pickup was wired to the former passive system volume pot, which worked fine, before i started is shown with black connected to vol pot tab with white and bare earthed to back of pot.

45 minutes ago, Geek99 said:

Did you check continuity on straps?

suggest you post a face-on image and detail the connection colours and purposes 

continuity seems fine both straps, getting reading to 0 ok so not a poor connection.

the connections are a bit of mystery, the kent armstrong sheet doesn't label each wire just gives different wiring for dpdt switch, vol pot and jack, nothing for blend pots.

the harness wiring paper is of little help because it shows connection for 2 wire pickups only and a single row of tabs on the blend pot image rather than 2 rows. Chinese i expect.

attached both with the image of the wired blend pot again.

warman have a wiring guide online but not sure if KA follow that same wiring.

That's how it is wired now but nada. 

11 minutes ago, Geek99 said:

Yes, but you need two 

that single wire is not obvious in your first image, but you do need two 

Like this? 

Short black wire added across. 

Still not working. 😕

26 minutes ago, paul_5 said:

That joint in the bottom left looks dicey at best.

 

solder joints should be bright and shiny- are you using rosin cored solder or flux? 
 
Your iron might need the temperature adjusting too if possible - dull joints can be a sign that your iron is too hot.

Best thing to do is remove all of the solder from the pot lugs, cut fresh ends on the wire, then twist and tin them. Insert both ends into the solder lug, then solder them both to the pot at the same time.

 

Also, it’s worth putting a crocodile clip across on the lug you’re soldering as a heat sink so you don’t damage the pot with heat. 

Always turn pots to full counterclockwise before soldering them too - this reduces the risk of damaging the track inside with the 200 degree iron..

sorry if that’s a lot, I’m just sharing the wisdom of my years of building, and the stuff that I learnt the hard way when I was starting out.

thanks for advice.

that dodgy solder was me i think, removed some solder by mistake.

the solder i have is a lead free a 0.7mm alloy sn99% cu 1%. stuff from Rapid. Says 22SWG on it. The soldering gun is 15 watts.

my experience is clearly limited, have done some simple  passive p bass 2 control repairs sucessfully but never dealt with a blend pot, that's why i bought the whole harness. Living in the back of beyond i dont have easy access to guitar techs, 3 hour trip down to glasgow. Can usually work things out myself but am wasting a lot of time on this job.

per the stewmac link schematic should i put an earth wire across the top left to bottom right tabs? Then put the 2 black pup wires back to the middle tabs?

There is a short wire crossing the 2 pan levels, 1st pic didn't show it. 

Have tried all ways of hooking my 2 KA soapbar humbuckers to a new active eq wiring harness's blend pot. 

Multimeter tell me the pots all work. 

Black wire from pups is the live, red and green are tied off, soldered and taped off. This worked fine onto the former passive circuitry Vol pot.

White and bare get earthed onto pot side( blend pot back is open). 

The blend pot is wired as it arrived. 

Frustrated. 

Where am I going wrong? No sound at all. The 9v battery is good, jack is good. 

TY

I've just sold one of these, stuck with it for 4 months from new but in the end the narrow string spacing killed it for me, too tight for me. Bought it online blind so lesson learned re trying before buying. Got it on sale price so didn't lose much selling on.

Found it great for scalar stuff, arpeggios and chords but no good for slap. Ended up playing it more like a guitar than a bass. There is insufficieint room under the D and G strings for popping without fingertips catching body. Also I could not do a double pop on G and D strings together because of the closeness of strings.

Too much contact with neighbouring strings generally, guess my hands are too big for it or just not dextrous enough to play it.

Shame, looks gorgeous and is light to wear, balance is great, sounded good (if a little too bright for my liking).

Optons to modify to install a wider bridge and wider nut notches weren't good because of the narrow neck limitation. Measurement across the fretboard at 24th fret is about 9mm shorter on the cort than my yamaha plus on the cort the outer strings sit well inside the fretboard edge so the difference is even more. I need my 19mm spacing on a bass. Even with them adjusted to max spacing on the cort was still way too narrow.

Hello,

I have a late 90s Yamaha RBX765a 5 string i acquired this week. It's in very nice shape but the electrics have been redone to make it passive instead of active (as it was orginally) and the front yamaha pickup has been replaced with a Kent Armstrong.

Some queries on the electronics.

Original wiring for this model's 4 pots (for 2 pickups) was volume / bass / treble / pickup blend per attached drawing.

Currently it has been wired for master volume / front pup volume / rear pup volume / tone.  The wires to the battery compartment are snipped so unconnected. Neither of the individual pup volumes work without the master volume turned up first. Dont like it like this. See photo, annotated T tone MV master volume, V volume x 2.

Looking to restore back to either original arrangement or go for 2 volumes and 2 tones and do away with the master volume.  

 The 3 volume (yes 3!) pots are rated B500k and the tone pot A500k, all made in Japan. I dont know if these are original pots (guessing not).

Can I change this without replacing pots? Or do tone pots always have to have a capacitor on them?

Looking further ahead I may look to the EMGs solderless 45 size pups if teh above doesn't work out. I like the neck on this 5 string so much it's likely a keeper and happy to upgrade in time. The pup cavities are the size of the EMG45 6 string range but as long as it's a bar magnet rather than poles it will work fine for a 5 string, I understand? 

If I was getting a pair of the EMG45 pickups is it right that some cant utilise a pickup blend pot, they need separate volume and tone controls?

Anyone advise what they think is best would be appreciated.

thanks