freestompboxes.org

Does anyone have a schematic for the Demeter BEQP ?

Rcustoms....it looks like the 3 band bass EQ of the Seymour Duncan bass preamp. Bass (boost)90hz, mid cut 575hz, bass 32hz, mid 650hz, and treble 5khz. Using a bandpass EQ filter.

darmstat wrote:Rcustoms....it looks like the 3 band bass EQ of the Seymour Duncan bass preamp. Bass (boost)90hz, mid cut 575hz, bass 32hz, mid 650hz, and treble 5khz. Using a bandpass EQ filter.

maybe i found many circuit based on.like jackson electronics guitar eq booster copied for esp and other brands

Rcustoms...I have this for a schematic so far. It is rough so be gentle....lol

darmstat wrote:Rcustoms...I have this for a schematic so far. It is rough so be gentle....lol

looks so good,good work ,is the definitive schematic or rev 1

rcustoms wrote:

darmstat wrote:Rcustoms...I have this for a schematic so far. It is rough so be gentle....lol

looks so good,good work ,is the definitive schematic or rev 1

the last model of fender basses(i don't remember which one) use this little demon,recently i install one, on an ibanez sound gr and is amazing what he does with a cheap pickups.

Just in case someone's still interested: Here's a pcb I did for the Silent Fly’s Sadowsky Preamp schematic on the third page of this thread. I liked the sound a lot better with J201 transistors, drain voltages adjusted to about 4.4 V each. Replace R4 and R7 with trimmers to adjust the voltage.
Cheers, Lars

darmstat wrote:Rcustoms...I have this for a schematic so far. It is rough so be gentle....lol

The 1M resistor at the input... goes to ground or to Vr?

Edit: I mean, in the Curbow schemo

looks awesome baja, I might just give this a spin. wondering if I should try my buffer-before-blend concept with this design... it worked fantabulously with the Music man design.

Hi all, I came across the Yamaha BB604-605 bass service manual with schematic.The preamp has built in NE-1 parametric EQ for midrange control. Original PCB is double sided so I redesigned to single side PCB. I have not built it yet but have plan to do. On my PCB I designed the way that IC's are mounted on track side , but if legs are bent backwards it will fit as normal. If there are interest to make this preamp feel free to use or modify these files. The PCB is drawn on Sprint Layout 6.

EWS Trilogic here : viewtopic.php?f=7&t=16263&p=232387&hili ... ic#p232387

But no conclusion at the end. Perhaps they need Mr Bajaman magic touch ?

Curbow Eq

Not my work, all credit goes to khutch on Talkbass.

See http://www.talkbass.com/threads/fender- ... es.934190/









(Apologies for the huge pictures.)

bajaman wrote:okay - here are some graphs
the first is normalized to all controls flat (mid way)
then: full bass boost, full bass cut, full mid boost, full mid cut, full treble boost, and finally full treble cut.
enjoy
bajaman

Hi, i don't know how to read these grafs on page 5. I'm curious what is center frequencies of these preamp.
Thanks for help!

Are C13 electrolitic or no ?

Guys

What about using charge pump to increase the available voltage adding more headroom? Does it short the battery life?

Hi here I traced Bartolini MK I onboard preamp using pictures from web , maybe some one do have one and can measure or already know smd capacitor values?

lietuvis wrote:Here is another interesting bass preamp (has minor errors) with variable low pass filter and switchable Q found on other forum.

Just curious which forum that was, I don't remember ...

(based on the file-names I'm fairly sure I did make those scans from a Dutch magazine)

Bye

clintrubber wrote:

lietuvis wrote:Here is another interesting bass preamp (has minor errors) with variable low pass filter and switchable Q found on other forum.

Just curious which forum that was, I don't remember ...

(based on the file-names I'm fairly sure I did make those scans from a Dutch magazine)

Bye

Well it is you by the name on the other forum, thank you for sharing, but if you want it to be removed ask administrators to delete it.

No problem at all, only glad it might be of use. Was just curious where I had posted it - DIYSB ?

Have a good wknd

Silent Fly wrote:Based on the indications supplied. It should be correct:

Sadowsky-pre (1.1).gif

Digging this Sadowsky preamp up from page 3.
It makes sense to have treble-cut as well, and that has indeed been added as the VTC (Vintage Tone Control...)

So you have four controls in total: Bass-Boost, Treble-Boost, Volume and Passive-Tone (Treble-Cut).

There are reasons for putting the Passive Tone control before the preamp,
as well as for putting it after the preamp.

Just curious, anybody an idea what the original does here ?



Bye