The preamp can still colour the sound when in passive mode. It certainly did with that Aguilar.
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Aguilar OBP-3 passive tone ...?
- Thread starter madjazzbass
- Start date
No it cant. (Unless you have miswired.) An active/passive switch is simply a true-bypass switch. When you go into passive mode, both the input and output of the preamp are disconnected from the circuit, and the volume pots go directly to the jack.
With a Bart pre amp and hum canceling Lindy's (at least on an M4V), only the passive tone control works in passive mode (thanks Einstein) and the bottom stacked knob is useless.
When you activate the preamp, all three work - the passive control works as a tone shaper, as well as the bottom of the split knob(bass) and the top of the split knob(highs).
Not sure how other preamps work, but I think that's how Mike sets up his standard M4V's. I was wondering what other preamps work with Mike's standard M4V set-up?
Well, I could hear an obvious difference. I had the wiring checked and it was fine. I've talked about this with other guys who have agreed that the passive tone will vary depending on the preamp. Might not line up with how things are ''supposed'' to work in theory but there you have it.
Sadowsky preamp with the stock Seymour Duncan pickups.
Geeez, Is Bassmods the Only ones that have a preamp with an Active/Passive Switch (push/pull) where you still have control of your Tone in passive mode? ... (I don't want another Bassmods preamp, they "color" the sound/tone too much)
It depends on how you wire the preamp. As was mentioned earlier, most preamps (Aguilar, Nordstrand, Audere, Sadowsky, etc.) can have a passive tone control added, even if the pre-wired harnesses don't come with one.
It would also probably be a good idea not to start duplicate threads, which is also annoying.
The passive tone control is just that. It is a passive tone control; NOT a part of the preamp. In your case, it remains in the circuit in both active and passive modes, because that is how the guy wiring the bass chose to wire it.
This is exactly what I have on an American Fender Deluxe Jazz and it sounds incredible. Great combination.
I think that you are misunderstanding the way that preamp configurations work. Having a passive tone control is not a feature of any preamp. Rather, it is a particular wiring choice that the end user can make, when wiring up the preamp. It is kind of like building something out of legos. You have all of the building blocks, and if you want to build something in particular, you just snap them together the way you want them. Likewise, pots and switches and capacitors are your building blocks, and you solder them together the way you want them.
If you want a preamp with a passive tone control that works in both modes, simply wire in a tone control, tied to the output of the volume pots.
i really liked the passive Tone control to be working All the time ...! in my Sadowsky , it made nice adjustments in active mode ..! as well as passive ...
The guy wiring it was the guy who made the bass. Is there a standard when it comes to including/bypassing the passive knob in the preamp section?
I'm asking because when I talk to a tech about doing it for me, I'd kinda like to be a bit more informed than I am now.
Basically, there are no 'standards' in wiring, as manufacturers change them from time to time on even the same model.
Usually, a passive tone knob is not included with an active preamp, but sometimes they are. AFAIK, when they are wired with a preamp they are either avail with or w/o the preamp in the circuit, meaning that they are either switched in (which adds pot resistance before the buffer) when the preamp is bypassed so the signal when buffered/preamped is not affected, or left in regardless whether the preamp is switched in or not, but (if using passive pickups) the tone pot will affect the signal even going thru the preamp.
All depends on who wired it and why they chose to do it the way they did.
Usually, a passive tone knob is not included with an active preamp, but sometimes they are. AFAIK, when they are wired with a preamp they are either avail with or w/o the preamp in the circuit, meaning that they are either switched in (which adds pot resistance before the buffer) when the preamp is bypassed so the signal when buffered/preamped is not affected, or left in regardless whether the preamp is switched in or not, but (if using passive pickups) the tone pot will affect the signal even going thru the preamp.
All depends on who wired it and why they chose to do it the way they did.
Hopkins
Commercial User
And the fact that it was so boomy and mid scooped in passive means that the preamp was being fed a boomy mid scooped signal to begin with.
Mine too, however most of the time I play mine in passive, only switch to active when I want a modern sound or for aggressive slapping.
Aguilar Super Singles pickups with Sadowsky Pre with VTC. Volume, balance, VTC (vintage tone (passive) control, passive/active push/pull), active treble, active bass.
Hopkins
Commercial User
The guys you talked to were wrong. When using an active/passive switch that is wired correctly the preamp is completely removed from the signal.
Like I said, I noticed a significant difference. Had the wiring checked and everything seemed fine. Active tone controls did not work in passive mode (so that wasn't an issue). Live the bass could not sit well in the mix in either mode. I considered selling the bass because I figured that the passive signal should be neutral. It wasn't. Switching preamps meant that in passive mode the bass suddenly sat properly in the mix.
