1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  
     
    TalkBass.com has been uniting the low end since 1998.  Join us! :)

Rewiring my Ibanez SRX - V/T/V/T using toggle switches

Discussion in 'Pickups & Electronics [BG]' started by Fat_Bottom_End, Jan 6, 2012.


  1. I have several Ibanez SRX basses and love them. That being said, I have no real use for an active EQ on a bass so I want to make it passive. I wired the pickups to the output to check the tone that way and it was actually better than with the electronics in. (By better I mean the waveform was more consistent without spikes and by ear the spikes turned out to be boomy peaks) Alright, so here is what I want to do. I want for on/off toggle switches - 2 switches to turn each pickup on and off, and 2 switches to go between bright and dark on each pickup (think tone knob maxed/cut aka bright/dark). I know that will sound crazy to some, but I don't use a volume knob except to mute my bass, and I usually only use a tone knob in the max position or all the way down. This brings me back to not needing active electronics... The only pot I would use is the treble to cut treble sorta like a tone knob being turned down. All this being said, should your standard .047 cap attached to the tone switches work like a tone knob only allowing maximum/minimum tone and would I need any resistors for the volume switches to mimic the vol pots, or since I already did the straight from pickup to output test and liked it, then I am assuming resistors to replicate the pot aren't really needed. I am really just fielding suggestions to completely understand everything before proceeding.
     
  2. Also after further listening to the recordings I noticed there is a slight bit more high end coming through with the straight to output. I have read about that being due to no 250k or 500k resistance from a volume pot. Just an update...
     
  3. Having tone switches on each pickup is useless. They will effect both pickups when both pickups are on.
     
  4. Why? It would essentially be the same thing as having 2 tone knobs? When you have both pickups going on a standard v/t/v/t bass the tones knobs work individually for each pickup allowing you to roll the treble off one pickup but not the other and vice versa...
     
  5. No they don't.
    When you have two pickups running in parallel, their tone pots are also running in parallel. The tones only function independently when either volume is rolled down far enough to place a series resistance between the pickups that is great enough to keep one tone pot's capacitor from bleeding the other pickup's signal to ground, or, when the pickups are soloed.

    You could get around this by adding a few resistors in series with the signal paths, but that will kill output/treble.
     
  6. So why would bass manufacturers put this setup on their basses then if they extra tone knob is useless? I am having a hell of a time believing you on this since I have owned several basses over the years with an individual tone knob for each pickup. I run volumes full blast generally for each pickup most of the time and used the tone knobs to dial in tones. Generally speaking, I usually would max a tone knob on one pickup and all the way down on the other to get a tone, max both tone knobs for another tone, and all the way down on both for yet another tone. By your explanation, there should be no difference in the sound of both being all the way down and only one being all the way down. That being said, there was a big difference in tone between the 3 settings which is why I am having a hard time with what you are saying.
     
  7. Very few manufacturers do a VVTT setup, unless it's with a pickup selector switch.

    If you look at the simple nature of the wiring, putting two pickups in parallel makes them one signal, causing both tone pots to act as masters. You hear a different tone with both tones turned down, rather than only one turned down, because that increases the total capacitance of the filter, which shifts it's cutoff frequency downward. The reason for the tone controls each sounding different is likely that there is a different value capacitor on each. They should still both act as masters, however. When both pickups are turned on, with both volumes up, the the neck pickup's tone pot affects the bridge pickup, and the bridge pickup's tone pot affects the neck pickup. If your basses do provide truly independent tone controls, which each affect only their respective pickups, that would indicate that there are either resistors in series with the signal paths, or perhaps active buffering.
     
  8. I know for a fact that the Peavey I owned had independent tone and volume for each pickup. I had changed pickups out on it and it had no active element and just had .047 tone caps on the tone controls. No resistors or funny biz, just a pretty simple straight forward wire up. I cannot tell you now exactly since I have sold the bass, but at the time I had switched out all of my tone caps with orange drops. Seems like most of the time I get on here and ask about something, I end up with far more questions. I don't doubt what you are saying is true, but there must be some sort of way to do what I want since I have seen it done using knobs in other basses that are passive, and able to do it without resistors and the such which are just tone suckers really. I am now more frustrated than before with no real explanation still on how that bass was wired with v/t/v/t and each tone being independent of each other. I think I will probably just go bang my head against something til I pass out...
     
  9. Are you sure about that? It defies the physics of the wiring you described. Either the tone pots interact when the pickups are directly parallel, or the wiring is non-standard.

    In any case, for what you are trying to do, you are going to end up with two tone switches that both affect the entire signal, when both pickups are turned on, unless you want to isolate the signal paths with resistors.

    Perhaps it would be more useful to opt for one tone switch which selects between two capacitances and a bypass setting.
     
  10. Not only do I believe you, I believe the research that I have found confirming what you are saying. This still leaves me wondering how I had a bass with this configuration... I mean I had this bass for a few years. I just went to Peavey's website and confirmed that I wasn't crazy. 2 volume and 2 tone is listed on the .pdf spec sheet just like I remembered. I loved that configuration and is why I wanted it again. Well hell...
     
  11. From the .pdf:

    BRIDGE PICKUP
    Peavey® USA Design
    Construction: Humbucking
    Magnet Type: Ceramic 5 bar.
    Description: Humbucking, dual coil, fully encapsulated, harmonically positioned for enhanced high end and attack. 15.5k DC.
    NECK PICKUP
    Peavey USA Design
    Construction: Humbucking
    Magnet Type: Ceramic 5 bar
    Description: Humbucking, dual coil, fully encapsulated, harmonically positioned for neck. 13.5k DC
    HARDWARE
    Black chrome plated
    Tuners: 19-1 ratio die cast, enclosed machine heads, 2+2 arrangement.
    Bridge: Heavy duty die cast, 3 way adjustable saddles, string through body.
    Controls: 2 volume, 2 tone, Die cast knobs.
     
  12. Not that the .pdf proves anything, but it at least shows that I am not remembering incorrectly. lol
     
  13. THand

    THand

    Jun 9, 2008
    SO has this been done yet or not?
    I've been thinking about converting mine to passive (with VTVT mainly cause it has 4 holes in the body).
    line6man, are you saying this won't work? It's a bad idea? Or that things will still affect each other, but not necessarily in a bad way?
    I'm not going to use switches...just volume, tone, volume, tone. Like a stack jazz w/o the stack. Bad idea?
     
  14. No, I didn't mess with it. I know it can be done (since I have found proof that it is done) and I have owned a bass with that setup in the past. I have read that it cannot be done, and been told it cannot be done, yet it is. Line6man never replied to my proof of it... I actually just converted 1 of my SRX basses to passive with volume/tone/blend and a dummy knob to fill the other hole. I did volume/tone/3 way pup switch on another of mine and just cut the front of the cavity out of the body and made a pickguard for it.
     
  15. It does not work well, for the reasons I described above. Some people find the two tones useful when the volumes are rolled back a bit, or for increasing the total capacitance, but it does not work as it is supposed to, for independent tone controls.

    You are arguing with physics. Draw the schematic of the circuit and you will see why it does not work when the volumes are on full. If your experience is any different, you have either used the setup with fixed resistors to isolate the tone pots, or you are confusing the effects of varying capacitance with independent controls.
     
  16. Awesome Sauce

    Awesome Sauce Already tired tomorrow

    Dec 21, 2011
    NW Chicago 'burbs
    Sig'd. :)
     
  17. Yay! Lol.:hyper:
     
  18. I never said I wasn't using a setup with fixed resistors to isolate the tone pots, hell I really don't know how it was wired but it worked as I have stated and I have found more basses done the same way. Cannot find a schematic for you though. And by the way, you just admitted that it can be done in your post with fixed resistors. LMAO
     
  19. I just thought I would add this little bit of info I just ran across -> Rickenbacker 4003's are setup as V/T/V/T just as I stated (other Ric's may be set up the same way, but that is the one I saw in action). There are video's online showing the use of them and how they change the tone. So it looks like others have argued with physics and won. Why are you people on here so be all end all with your opinions? Cannot this, cannot that. I have proved a few times in this post that different manufacturers do it, yet you sit hit and tell me again and again it cannot be done. I find more frustration @ Talkbass than anything else it seems unfortunately. :(
     

Share This Page