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JayB
Senior tube assistant
Posts: 135
(6/11/05 4:47 pm)
Bass boost?
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How would you do a bass boost? I'm scatching my head on this one. Something to make it fluid sort of the woman tone.
tubenit
Hey get your own solder
Posts: 284
(6/11/05 8:06 pm)
Re: Bass boost?
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When I think of the "woman tone", I tend to think of a mid-boost (and sometimes increased gain) rather than bass? If you play with the Duncan Tone Stack calculator, it impresses me that the mids may be what you actually want? I realize the concept of the "woman tone" is someone subjective. Guess it depends on the women you know? Increasing the mids makes an amp sound more "bass-y" and mid-ly, IMO. On a Fender tone stack you could have a SPDT using two different resistors to ground with the larger resistor boosting the mids. I changed my Princeton Reverb mid resistor to 22K from the original 6.8k. (from top to bottom on the tone stack schematic, I did 390p/.047/.022/22k)
I also have boosted the mids by adding larger cathode caps on V1 and also on the shared cathode of a pair of 6V6's. I've used as large as 47uf/100v on V1 cathodes and currently am using a SPST to parallel switch a 47uf/100v cathode cap to ground on the power tube shared cathode/s.
Yet another option to boost mids might be to use a SPST to switch the 2nd half of a V1 preamp tube to be paralleled for about a 30% increase in gain with little to no increase in noise.
A last thing I've done before is to create a bypass switch to completely bypass an entire tone stack which increased the mids and gain dramatically. OR to lift the ground on a tone stack which can bypass all of most of it.
Change in speaker can sure boost mids and bass. I put a Weber 10A100 in my PR and that helped bass and mids alot.
JayB
Senior tube assistant
Posts: 136
(6/11/05 8:42 pm)
Re: Bass boost?
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Thanks tubenit. I completely forgot about the midresistor. I guess I could solder a 20k from the pot to ground in parallel to the ground connection with a switch. I'll try that. I'm looking for that thick lead tone. Maybe I'm asking to much from an home brew amp design when I could just as easily turn the tone down to zero on the guitar.
tubenit
Hey get your own solder
Posts: 285
(6/11/05 8:55 pm)
Re: Bass boost?
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Thought of another thing that might be worth trying. All 3 of my amps use 6V6's and I've added on several of them 2.2k resistors on pin 4 (grid). Kind of hard to describe the change, but I think it gives it sort of a more compressed sound (kind of like you'd get turning down the guitar tone knob somewhat). Keep in mind that the tone you might like for jamming at home might not cut thru with a live band. Hope whatever you do works out for you. Let us know what you find out. tubenit
ampcabinets
Hey get your own solder
Posts: 213
(6/11/05 11:45 pm)
Re: Bass boost?
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I am really impressed with the tone stack calculator.
It really seems to it easy to try different tone setups, especially between different channels. I set the 2 channels on my showman totally different, making it a favorite to play around with. Channel one sounds more like a marshall than a marshall. Channel 2 is straight off the shelf fender showman.
rob
HotBluePlates
I only work on Fender's
Posts: 1214
(6/12/05 5:44 am)
tone stack change
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Another option to add/change the mids in an amp is to change the slope resistor of the tone stack. If you have a tweed bassman/blackface style tone stack, then if you changed the stock 100k resistor between the treble and bass caps to a smaller value (say 33k), you will change the freq. that the mid-dip occurs as well as how deep that dip is. Use the Duncan tone stack calculator to see the effect. Then you can make it switchable. While you could use a pot to find the resistor value you'd like to use there, I wouldn't recommend a pot for the final control, as it will have d.c. on it and sound scratchy. Adding a cap to block the d.c. would probably alter the effectiveness of the tone satck and/or change its sound.
You could also change the presence circuit in an amp (assuming you have one now) to act as a resonance control, and reduce the feedback at low freq., which would increase the bass. That would be the same action as having a presence control, but acting on the other end on the freq. spectrum. A couple of books in the Ultimate Tone series outline resonance controls. Maybe someone can post a scan from one of those (I don't have a host for posting pictures).
Tyrannocaster
I only work on Fender's
Posts: 574
(6/12/05 7:59 am)
"Woman tone"
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If you actually want what's commonly referred to as the "woman tone" you will have to get it using your guitar. Of course your amp is important, but the sound really comes from a neck humbucker with the treble rolled all the way off. You don't do it on the amp at all, although you can certainly modify it. But no amount of amp tweaking will help if you don't start with the guitar first.
Matecaster
Junior tube assistant
Posts: 5
(6/12/05 4:29 pm)
Woman tone
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Starting with the guitar was true in my case. I heard Clapton changed his guitar tone control cap's from .05 to .02 this keep's the tone control usable all the way down. Work's best with cranked amp. I use .01's in my Tele and am pretty satisfied.
JayB
Senior tube assistant
Posts: 139
(6/12/05 7:02 pm)
Re: Woman tone
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That's what I ended up doing. The paul had a .05, so put in a .02. That made it much better. Usable with the tone all the way down. No mud. I'll keep the other ideas for more modding and experimenting. The adjustable slope resistor works great though! I used a 33K in series with a 100k pot. Dial just about anything in with that.
ampcabinets
Hey get your own solder
Posts: 216
(6/13/05 1:29 pm)
Re: Woman tone
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I experimented with a few dozen pickups and caps, before I got the tones I wanted from the front, middle and rear pickups in my 68 strat. I also experimented with different wirings of the 5 way switch, changed from the original 3-way. I also changed the 250K volume pot to 500K for more overdrive from the pickups. About 3/4 the way up stays clean.
I experimented with different caps in the LP until I got the desired tones. I usually make the front "womany" and the rear a bit "twangy". The combinations usually make for really full sounds.
The Kramer Focus 3000 has EMG (S-S-H) active pickups, which do about anything you want, with few changes in the original circuit.
My custom built Tele and matching Strat have totally "rob" circuits, which I designed and implemented in these guitars, after much experimentation. My luthier put the guitars together for me, though, as I am more of a cabinet builder, and ELT, than luthier. Way more.
My next guitar is a custom SG style with [ p-90, dual strat style(from an old guitar), p-90 (3 pickups)] and custom circuitry, including 5-way switch. The body of which, is due any day. We have already layed out the electronics and are waiting on the body before fitting a neck to it. We are still debating about 4, 5, or 6 controls.
Maybe Duncan can come up with a calculator for guitar tone circuits. Wouldn't that be nice?
by the way, Clapton also has a mid boost circuit in his guitar, available from a variety of sources. It goes underneath the pickguard, forward of the controls, and uses a push pull type switch on one of the tone controls to activate it.
rob
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