4004Cii Bridge Pickup Tone

[Isaac]

I've noticed that the neck pickup is considerably louder than the bridge pickup. Eventually, I intend to install a push-pull pot to select single coil on the neck pickup, but I think I'll try wiring the neck pickup in parallel. That should reduce the output, bringing the pickups into closer balance.

[Isaac]

Rehearsal was canceled last night, so I had some free time.

I decided to go ahead and wire the neck pickup in parallel. I also had a 500K pot with a switch handy, so I used the switch to allow both parallel HB and SC operation. Wired it all up, and it didn't work. Checked all my wiring, and found that I had wired the new pot backwards. Fixed that, and tried it again. Worked great! The bass is much brighter now, with the 500K pot. In fact, the original pot, which should have been 330K, measured under 200K. Same with the tone pot.

The odd thing is that I couldn't hear any difference between HB and SC operation. So here's what I'm thinking. Two virtually identical pickups (the two coils of the HB) in almost exactly the same position on the bass really ought to sound almost exactly the same. In parallel, the output impedance is lowered, but the output voltages don't add together as they do in series. So I guess it makes sense that it sounds the same either way. Still, it should be a useful mod. In SC mode, the two pickups form a HB pair. When the neck pickup is soloed, I can put it into HB mode by itself.

Anyway, I'm looking forward to trying it out in rehearsal and at a gig.

[woodyng]

Rehearsal was canceled last night, so I had some free time.

Worked great! The bass is much brighter now, with the 500K pot. In fact, the original pot, which should have been 330K, measured under 200K. Same with the tone pot.
Anyway, I'm looking forward to trying it out in rehearsal and at a gig.

Yep,brighter and bolder.....no loss of that great bass tone,either. It's the aural equivalent of removing a wool blanket from over your speakers....

[Isaac]

I'm going to have to add a midrange speaker!

[jps]

I'm going to have to add a midrange speaker!

If you do, get a good (proper) crossover made for it. I have a couple of LDS cabinets with really nice sounding Faital Pro W6N8-120 mid drivers.

[Isaac]

My main rig these days uses a Crown XLS1500 power amp. It has a built in crossover. I also have a Biamp crossover I could use with another amp, if I wanted to.

[jps]

What is the range of the crossover frequencies on the Crown and what are the slopes of the hi-pass and low-pass sections?

[Isaac]

Copied from the manual:

The PureBand™ Crossover System provides a variable state Linkwitz-Riley 24dB/octave filter allowing you to choose a point between 50Hz and 3kHz on 1/12th octave centers. The following points are available for choice:
50Hz, 53Hz, 56Hz, 59Hz, 63Hz, 66Hz, 70Hz, 74Hz, 79Hz, 83Hz, 88Hz, 94Hz, 99Hz, 105Hz, 111Hz, 118Hz, 125Hz,
132Hz, 140Hz, 149Hz, 157Hz, 167Hz, 177Hz, 187Hz, 198Hz, 210Hz, 223Hz, 236Hz, 250Hz, 265Hz, 281Hz, 297Hz,
315Hz, 334Hz, 354Hz, 375Hz, 397Hz, 420Hz, 472Hz, 500Hz, 530Hz, 561Hz, 595Hz, 630Hz, 667Hz, 707Hz, 749Hz,
794Hz, 841Hz, 891Hz, 944Hz, 1.00kHz, 1.06kHz, 1.12kHz, 1.19kHz, 1.26kHz, 1.33kHz, 1.41kHz, 1.50kHz, 1.59kHz,
1.68kHz, 1.78kHz, 1.89kHz, 2.00kHz, 2.12kHz, 2.24kHz, 2.38kHz, 2.52kHz, 2.67kHz, 2.83kHz, 3.00kHz

[woodyng]

Jeff,you had to ask.....

[jps]

Good, sounds like you can easily integrate a mid driver.. Can the two channels be output through a 4 pole Speakon connector (like Gallien-Kruger does on their 700RB/1001RB series of amps) to avoid running two separate cables to the speaker cabinet?

Woody, sometimes you just have to ask for details, and other times you have to run away from the scene.

[woodyng]

[Isaac]

I hadn't thought about using a 4-pole connector. As things stand, the speakers I'm using with it are all 15"s. I was thinking of using an external cabinet with an 8" or 10". But it wouldn't be difficult to wire in a 4-pole connector in the back of the rack.

[jps]

I hadn't thought about using a 4-pole connector. As things stand, the speakers I'm using with it are all 15"s. I was thinking of using an external cabinet with an 8" or 10". But it wouldn't be difficult to wire in a 4-pole connector in the back of the rack.

That would be very nice, then you'd look a real pro with that arrangement.

[Isaac]

That would be very nice, then you'd look a real pro with that arrangement.

I wouldn't want to mislead anybody!

I suppose I might have left out the actual available frequencies, but he did ask.

[cjj]

Copied from the manual:

The PureBand™ Crossover System provides a variable state Linkwitz-Riley 24dB/octave filter

Jeff,you had to ask.....

I always find it cool to see people posting anything about Linkwitz-Riley filters and all the places they seem to get used. I used to work with Siegfried back when I started at Hewlett-Packard. Cool guy...