A way to know is to remove the battery and see if you get a signal in passive mode.
The models I’m checking out SR1825 and SR5CMDX both have EQ bypass which isn’t true bypass. It’s odd cause they’re high end models.
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Which active basses have true bypass, passive tone control etc?
- Thread starter Stagelab
- Start date
The models I’m checking out SR1825 and SR5CMDX both have EQ bypass which isn’t true bypass. It’s odd cause they’re high end models.
Kubicki's have true active modes in both 9v and 18v electronics. Tone controls work in 9v version.
Indeed, I run both my Ibanez BTBs without the preamp and no battery the majority of the time. A number of the SRs have the same electronics config.
That is exactly what happens. I also don't know what that means, but I do know I don't need batteries.
Strange that the SR1825 and SR5CMDX wouldn't be the same.
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Yeah it’s strange isn’t it? I contacted Ibanez and they said these models don’t offer true bypass. Trusted source. No idea why they didn’t wire them for true bypass. Ibanez circuits are notorious for excess wire and I’m guessing these models have circuit boards so modifying the circuitry for true bypass would be above my pay grade but I’m sure a tech could do it for hopefully not too much cash so that’s probably the route I’ll take.
The John East JTone preamp I installed in my Tribe Shob works like this. The passive tone is always active, but if you pull the tone knob up, you disengage the active eq. So if you take the battery out, you still have volume, blend and tone (as long as the tone knob is pulled up). I like the familiarity of a passive tone knob always being available, even when there is active eq.
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My Sandberg TT-5 Superlight (J5) has true bypass. It operates in passive mode without a battery, with the treble EQ knob becoming a passive tone control. Great setup IMO.
The G&L L-2000/2500 are different beasts, because the tone controls are entirely passive. One is a treble cut, the other a bass cut, and they operate the same in passive and active modes. When engaged, the preamp simply changes the output impedance, which does affect the tone slightly and prevents treble loss with long cables. It also has a treble boost mode, which makes it sound more like an active bass with the treble boosted. (I used to have the single pickup L-1500, which had a slightly different preamp. It had one mode, which included more treble boost than the treble boost setting on the L-2000/2500 basses.)
The G&L L-2000/2500 are different beasts, because the tone controls are entirely passive. One is a treble cut, the other a bass cut, and they operate the same in passive and active modes. When engaged, the preamp simply changes the output impedance, which does affect the tone slightly and prevents treble loss with long cables. It also has a treble boost mode, which makes it sound more like an active bass with the treble boosted. (I used to have the single pickup L-1500, which had a slightly different preamp. It had one mode, which included more treble boost than the treble boost setting on the L-2000/2500 basses.)
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My typical wiring setup for 2 pickups is a Nordstrand 2 or 3 band preamp, set up with volume, blend, bypass, passive tone, and a series/parallel switch.
The series/parallel basically disengages the blend and makes both pickups act as one big pickup.
PTC works in both active and passive mode (though I could wire it so it only functions in passive if needed).
If there is no battery, the bass still functions with all of the passive abilities.
The series/parallel basically disengages the blend and makes both pickups act as one big pickup.
PTC works in both active and passive mode (though I could wire it so it only functions in passive if needed).
If there is no battery, the bass still functions with all of the passive abilities.
This Roscoe Century Standard Plus has it:
Volume (push/pull active/passive) / blend / TONE / stacked 2-band boost-only lo & hi.
IME it's not quite the same experience as playing a good passive bass. But when I have to go back & forth between old-school & contemporary multiple times in a set, this has been really great. (I sometimes prefer to switch instruments – but there's not always room or time.)
I wouldn't say the passive tone circuit is an absolute 100% must-have on an active instrument... but it has become quite high on my priority list.
I would still make an exception for an active bass that lacked a tone knob but had its own amazing vibe. (Of which there are many.)
Volume (push/pull active/passive) / blend / TONE / stacked 2-band boost-only lo & hi.
IME it's not quite the same experience as playing a good passive bass. But when I have to go back & forth between old-school & contemporary multiple times in a set, this has been really great. (I sometimes prefer to switch instruments – but there's not always room or time.)
I wouldn't say the passive tone circuit is an absolute 100% must-have on an active instrument... but it has become quite high on my priority list.
I would still make an exception for an active bass that lacked a tone knob but had its own amazing vibe. (Of which there are many.)
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Seconded the Glockenklang I've the 3 band and you can use bass, mid and treble when battery flat or switched to passive.
Interesting. I have the 3-band in another instrument, but have never tried it without batteries.
I don't think anyone mentioned the Yamaha BB734a. It works just like the TRBX models referenced above -- in active, it's bass boost/cut, mid b/c, treble b/c. Switch to passive and the treble control works just like a regular tone control. No battery needed.
All of the Carvins/Kiesels I have owned are useable in passive mode without a battery, although none of them have a passive tone control. This includes various basses with their in-house preamps as well as one with a Darkglass Tone Capsule.
My Kiesel has a passive bypass switch. Don't know if there's a passive tone control or not. Probably not. I just set the tone controls flat, and use the tone controls on the Tonehammer pedal. I was going to add an Empress Bass ParaEq but so far, I've not needed it.
I've been using an LTD B-1004 Deluxe for about two years; Nordstrand Big Splits and a no-name 3-band preamp with a bypass switch for the preamp. It will play in bypassed mode even with the battery removed, but it doesn't include a passive tone control. I might have one installed at some point, but I really don't have any pressing need for that. I just cut my highs with the preamp when I go for a more vintage tone with less glassy bite, but it's also plenty snappy and hi-fi if I bump both the highs and lows.
This bass also sounds nice with the preamp bypassed, but the output is slightly lower than when the preamp is "on" and the controls are all at their center detents. Some on-board preamps have a trim control inside that can let us match the active output with the passive, but no such adjustment is available here.
This bass also sounds nice with the preamp bypassed, but the output is slightly lower than when the preamp is "on" and the controls are all at their center detents. Some on-board preamps have a trim control inside that can let us match the active output with the passive, but no such adjustment is available here.
Carvins used to... I think the Yamaha TRBX does but I have not looked under the hood to see how it functions.
My old LB76 went to V/T when you pulled up the volume pot. It worked without a battery so I am going with passive too
I believe my Yamaha BB1200S has true bypass with a passive tone control when the preamp is switched off.
Same here. That's why East pre's rule. Well in my world anyway....
Buy passive, add East preamp = problem solved.
