Preamp for L2000?

[Karl Kaminski]

Oh, and I've got some new knobs on the way, too.

I'll post a pic when it's all put together.

Any pics? Im thinking about "fitting" my Pope pre. If I were to keep it in there, I'd have to go with a "toggle-hole conversion" Im interested to see what you ended up with in there. (i'll run it "open-gut" to experiment... ill post a pic during my holiday break)

thnx

[Mr. Mom]

Forgot to post a pic! I'll get on that.

I like the tone of the Aggie preamp. And I really like how the levels are the same in passive and active mode. I switch on the fly without any other adjustments. (Usually keep it in active mode, though.) I also like the eq points. I can cut a little Bass and Treble and then boost 400 or 800 hz and it sounds real good and sits very well in a mix.

What I don't like about the Aggie pre....And this is kind of a big deal to me....Is that turn the Blend juuust past halfway (indent) and you're about 80-90% of the way towards the bridge pickup, blend-wise. Turning it the rest of the way does very little tone-wise. It's kind of hard for me to find that sweet spot. Other Blends on active pre's I've had are far more consistent and intuitive.

I tend to lean on the Bridge pickup quite a bit to cut through (bridge) but still have weight/girth (neck). And I really like finding all those tones that are "between" the pickups, if that makes sense. IOW, I use the Blend as an EQ far more than the actual EQ. It's kind of hard to do this with the Aggie.

IMO, YMMV, etc etc.

[Ken Baker]

What I don't like about the Aggie pre....And this is kind of a big deal to me....Is that turn the Blend juuust past halfway (indent) and you're about 80-90% of the way towards the bridge pickup, blend-wise. Turning it the rest of the way does very little tone-wise. It's kind of hard for me to find that sweet spot. Other Blends on active pre's I've had are far more consistent and intuitive.

Remember that the blend is actually on the passive part of the circuit, "ahead" or "upstream" of the preamp along with the volume control. Obviously, I'm thinking about the circuit I used when I did my L-2500. Electronically the L-2000 and L-2500 are the same. It's possible that the blend pot may be defective.

Ken...

[Mr. Mom]

What I don't like about the Aggie pre....And this is kind of a big deal to me....Is that turn the Blend juuust past halfway (indent) and you're about 80-90% of the way towards the bridge pickup, blend-wise. Turning it the rest of the way does very little tone-wise. It's kind of hard for me to find that sweet spot. Other Blends on active pre's I've had are far more consistent and intuitive.

Remember that the blend is actually on the passive part of the circuit, "ahead" or "upstream" of the preamp along with the volume control. Obviously, I'm thinking about the circuit I used when I did my L-2500. Electronically the L-2000 and L-2500 are the same. It's possible that the blend pot may be defective.

Ken...

Oh. So the Aggie Blend is passive? Like replacing the two volumes on a passive Jazz bass with a passive blend? I had not thought about that. I just ASSumed it was an active blend. And that would explain why I seem to get a pretty big passive-jazz-bass-with-both-pickups-all-the-way-up kinda tone with the Blend centered. Which I like! (I'm using that tone quite a bit at a contemporary Christian Christmas show where the bass is phhaaaat and phhuuul.) AND, that would explain why I seem to get more of that passive-jazz-bass-with-both-pickups-all-the-way-up kinda tone than I have with basses with active blends.

I must be used to "active blends" where both pickups are "on" 100%, 100% of the time and the blend is more of a volume knob between the two pickups. At least that's how I understand active blend controls?

[Ken Baker]

I must be used to "active blends" where both pickups are "on" 100%, 100% of the time and the blend is more of a volume knob between the two pickups. At least that's how I understand active blend controls?

Yup. "Active" blend would be a function of the preamp used.

Here is what feeds the OBP-3 in my L-2500:



The pickup select switch, which could easily be swapped out for a smart blend, is in its usual place; just after the coil switch. The volume control is also in pretty much the same position in the circuit as stock. From there it's on to the active/passive switch which feeds either the preamp or the jack (with the preamp totally isolated and grounded).

The OBP-3 does gain (for the most part) via the EQ controls. With all three centered there is very little gain, though the Aguilar voicing is present. Gain increase or decrease is a function of EQ. This is all very much like what Paul did with the preamps for the M series basses.

Ken...

[Mr. Mom]

This is all very much like what Paul did with the preamps for the M series basses.

Oy.....Which of course fuels my M2000 GAS. I'd prolly really dig the M2000.

Thanks, as usual, for the edumacation, Ken! Much appreciated!

Overall I'm happy with the Aggy pre. Using the preamp "color", with the EQ set flat, just plain works for me. It thickens the tone while also cutting through. Cliche terms but that's how I hear it.

I've been using this signal chain as of late and really dig it: Bass to MXR M87 Comp to MXR Bass Octave Deluxe to Aguilar THDI to Grace Felix. That signal sounds pretty freakin' glorious. The Grace Felix (and Alix and Bix) have custom wound transformers on the DI out that are, IMO, the best thing since sliced bread. They sound stupid good. I can also use the Felix's second channel as a really nice IEM amp for my IEM gigs. The MXR BOD only gets used at my church gig(s). I can kick it in and pump up a chorus or bridge whenever needed. Tracks my basses extremely well for an analog octaver. I just love the tried and true THDI. Sounds silly, but my stock setting is the AGS engaged, Gain allll the way down, EQ flat except some Treble roll-off, and Master set to unity. The M87 is my latest try at using a comp. I've had a few but never bonded with one. Until the M87. Very intuitive and easy to use. Really does help with adding weight and separation to individual notes without losing dynamics.

[mattrudy]

Ken, what's the layout of the knobs and switched with your 2500?

Switches:

Standard pickup select
Series/SC (outers)/Parallel
Active/Passive

Knobs:

Volume
Mid (300Hz center)
Stacked bass & treble

This is the circuit used. It only shows the feed to the OBP-3, which uses Aguilar's layout. Note that the active/passive switch fully isolates the preamp when in passive mode.



Ken...

Did the preamp come with the new knobs or did you have to buy those from somewhere else?

[Ken Baker]

Did the preamp come with the new knobs or did you have to buy those from somewhere else?

The knobs were purchased elsewhere. Maybe Parts Express?

Other than John East preamps that come on a Jazz plate, I don't know of any third party preamps that come with knobs. Pots, yes. Knobs, no. It's a subjective thing that the player gets to choose.

Ken...

[wneff]

I also did the upgrade to the Aguilar, but a little different:
- Bestbassgear has a pot with a 50 k and 250k stacked - I used that as a treble knob, the 50 K is for the active treble, the 250 k for passive roll-off in passive mode
- I have the active/ passive as pull - switch on the volume
- third switch is 400/8700 Hz center frequency

I find the bass is really bright - has anyone else expereinced that too?

[Ken Baker]

I find the bass is really bright - has anyone else expereinced that too?

Not at all, and I did not use a "swamping cap" to lower the resonant frequency of the pickups. In fact, I boost the treble a small tad.

The circuit above it what I used. Really simple until I threw in the OBP-3. Then it became a major rat's nest. Just a great sounding rat's nest.

Ken...