A few decades ago I did this to my Fender (tube) Bassman amplifier. The first time that I regretted a capacitor change. Changed it back to the original stuff and there was my fat sound again. Guitar amplifiers are not HiFi. We can still bother in extremes about capacitors after the recording has been done of that lovely distorted sound. Those contradictions are nice, aren't they? 🙂
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my active pickups they consider low Impedance though Like emgs which is why the 25K and 50K controls are used with them
Few more questions. Can I use ceramic caps instead of the 22UF electrolytic
and should I remove the one as I do not need the blend control for a one pickup bass
and should I remove the one as I do not need the blend control for a one pickup bass
Again: "sound does not come from parts but from design"
Although that Myth runs rampant in DIY Audio and most Forums 😱
No, C104 is needed because this is s single supply Preamp, so you need to block important DC (as much as 9V DC, go figure), both at input and output.
Now a single active pickup straight to that preamp input in principle will be "better".
How much better?
We should need to know said pickup output impedance.
Not suggested "load" impedance, but internal/generator impedance.
Again: adding a unity gain buffer, high impedance input, at the point I suggested, driving the tone control network, will improve things in a sensible way, because it will make tone control action/range independent from Bass pickup; you might even use a regular passive Bass pickup there and it will work fine.
Again: IF you want brighter/more defined/more "Hi Fi" sound, you should at least boost highs above 1600 Hz.
let me see the schematic again, maybe it can be easily modded 😉
Note:
I have been chastised for speaking about "treble murdering" ; yet your Spectrum display shows exactly that, in spades:
Mid/High response goes downhill like a snow avalanche.
And NO highs to speak of.
Oh well.
Let me see if we can improve that somewhat.
You are a legend!!Again: "sound does not come from parts but from design"
Although that Myth runs rampant in DIY Audio and most Forums 😱
No, C104 is needed because this is s single supply Preamp, so you need to block important DC (as much as 9V DC, go figure), both at input and output.
Now a single active pickup straight to that preamp input in principle will be "better".
How much better?
We should need to know said pickup output impedance.
Not suggested "load" impedance, but internal/generator impedance.
Again: adding a unity gain buffer, high impedance input, at the point I suggested, driving the tone control network, will improve things in a sensible way, because it will make tone control action/range independent from Bass pickup; you might even use a regular passive Bass pickup there and it will work fine.
Again: IF you want brighter/more defined/more "Hi Fi" sound, you should at least boost highs above 1600 Hz.
let me see the schematic again, maybe it can be easily modded 😉
Note:
I have been chastised for speaking about "treble murdering" ; yet your Spectrum display shows exactly that, in spades:
Mid/High response goes downhill like a snow avalanche.
And NO highs to speak of.
Oh well.
Let me see if we can improve that somewhat.
so this is the bass
Volume
Bass middle treble
no balance needed
But now buffer? If the pickup is internally active aren’t they buffered ?
Attachments
So in theory looking at the schematic
couldn’t I wire the pick up signal wire to C104 to go direct into it along with the cap ?
couldn’t I wire the pick up signal wire to C104 to go direct into it along with the cap ?
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I apologize….
since the preamps are so similar just being the mid shift
here’s the correct one.. I was able to find it
Minus the blend
Once again..
with that mistake..
I guess I’d be soldering to C105!
since the preamps are so similar just being the mid shift
here’s the correct one.. I was able to find it
Minus the blend
Once again..
with that mistake..
I guess I’d be soldering to C105!
With it being a quarter century old, it may help to replace any electrolytic capacitor in the signal path, as they can dry out and lose capacitance over decades This would lose frequency response in the low end. I'd use another electrolytic of the same value. I'd say do NOT use a ceramic, as they tend to be microphonic. The NP0 types aren't but I don't think you can get those at anywhere near 22uF. If you can find a 22uF film that physically fits, you might as well, though it may be expensive.
I ordered a 0.033UF NP0 cap to replace C103 and C104 in the new preamp I uploaded
And a CAP CER 0.1UF 50V BX RADIAL for C108
TLE2072ACP
47UF50V UKZ
And 22UF 50V Panasonic FR
and I have some 0.22 wima caps
I guess I could have ordered those
https://www.digikey.ca/en/products/detail/kemet/F611DY226K100ZLH0J/12178187
https://www.digikey.ca/en/products/detail/kemet/F611DY226K100ZLH0J/12178187
Follow the link in the quote header, eh?
The preamp with the 220K||470p is flat -1dB to 12.8KHz.
Attachments
Woah..
That’s cool!
But from playing POV it’s true. There’s not much sizzle happening until you really crank the knob.
and even swapping the pre out for others I’ve instantly noticed more treble like a blanket was lifted.. this bass though I’d want to keep it with the stock preamp though with some modifications to it
If you want to improve your bass guitar sound, use the amp that the incomparable James Jamerson used on the MoTown recordings---an Ampeg B-15. There's nothing better!
Positive towards tone control, which presumably has some +9VDC present, negative towards pickup which "should" have 0Vdc present.
Unless marked otherwise, the stripe shows negative end.
A ampeg b15? Tube amp?
Not even power and the cab could never handle a low B
Ha!
I run a Aguilar DB680 into a crown XLS poweramp and a GK neo 412