Torres guitar mid mod

[GibsonLover]

Does anyone know what value R, L, C is used on the Torres mid cut mod?
Any variations to make it more useful?

[thumbs]

It's a 1.5 henri inductor in series with a .039 cap and a 220k resistor in parallel. Very similar to the old R.A. Gresco Tone Qube. I prefer a little less cap. Sounds cool when used in moderation. Great for rhythm work.

[wolf1728]

I'm interested in building one of those Mid-Cut controls myself. If I've followed the description in this thread correctly, it should look like the graphic below.
It seems to me that either Diagram A or B would work, but I'll leave it up to the message board members to analyze this.

[Chuck H]

Do it like diagram A. That's the way Dan does it and it makes sense because you don't need to "float" any solder joints that way.

Good luck finding the 1.5h inductors by the way... I've looked and let me tell you, they arent out there. At least none you would put into the electronics cavity of a guitar.

Dan uses those little Xicon audio transformers available from Mouser at the end of the "inductors" section of the catalog. Part#42TL021 Snip off the three secondary leads and the center tap of the primary and use the two remaining primary leads. The primary side is marked with a P.

Chuck

[wolf1728]

Thanks for the quick reply Chuck.
I agree that large value inductors are very hard to find. I believe that the largest that Mouser sells is 150 mH, which is pretty small when dealing with tone circuits.
I guess I'll try using that transformer, as you suggested.

[Mark Hammer]

If one uses diagram B that wolf1728 showed, it is possible to wire the control up as a bidirectional tone control. Use a 500k or greater linear pot, and solder a cap (6n8 to 18n, depending on taste) from the other unoccupied outside lug to ground. Assuming the pot is of a sufficient value, when it is in the middle, there is no treble cut or mid cut. When rotated in one direction from the midpoint, you'll get mid-cut without treble cut. When rotated in the other direction, you get the opposite.

One person I recommended the bidirectional mod to was clever enough to use their dremel to create a centre "no-load" detente in the their tone pot.

[Chuck H]

Dan used to have a kit wired that way. I didn't care for it, but I'm that guy who's always checking to make sure my tone pot in on ten. The detent would be a big improvement. I'd still use a 1M pot to minimize loading. I know it would make the adjustment less linear but I'm ok with that. In fact it might be an idea to use a push pull pot so you could:

1) tone control in one position and mid control in the other.

2) tone/mid control as Mark suggested with the knob pulled and both deactivated when pushed to avoid any loading or wondering if your actually on 5 on a dark stage.

Chuck

[GibsonLover]

The inductors are not too hard to find. On another Varitone thread posted about the same time this one was, I followed up with measurements from a mineature Radio Shack output transformer, 10K to 8 ohms. Clip the secondary. The primary measured .8H at 120 Hz and 2.1H at 1KHz. It just depends where you want to scoop. Keep in mind there are only a couple parts to mess with, so just dive in. There is no Better or Best, because your circuit will be in parallel with the inductance and resistance of the pickup(s) you are using. In my case, I used Lollar CC neck and his matching bridge pickup. The circuit is on the neck (2.2K resistance). The guitar is a Tele wired as a modified Esquire / Broadcaster with the blend pot. Although the cap value does not match the Gibson Varitone Position 4, that's the sound I was after with the wiring shown. The guitar has all sorts of range in tone without the use of a tone pot. I have come to the conclusion (maybe like Chuck) that I only check a tone pot in the past to be sure it's still on 10, and is therefore useless to me. The photo shows the reverse control placement and the inductor epoxied between the pots.

[GibsonLover]

OK - That .BMP looks bad...

Here's a JPG > and it still looks bad. Maybe my machine, but use Save As if you are interested.

[Mark Hammer]

Yeah, ideally you want at least 500k of resistance in series with whatever it is you aren't using, whether mid-cut or treble cut. 1M is preferred so that you have 500k on either side of the midpoint, though if one has a no-load setting (i.e., open circuit) in the middle then you could use a 250k pot for that matter. The 500k-1M recommendation is simply for those cases where one is obliged to rely on the pot resistance itself to cancel the cut.

A push-pull pot would indeed be useful to select between the two options. Not all guitars accommodate all push-pull pots, though. I also kinda like the bi-directional thing because it compresses the full range of tone adjustment into half the degrees of rotation. If a person wanted to go all-out, and could find a 1M linear push-pull pot, you could use two different mid-cuts in one direction, two different treble cuts in the other, and use the push-pull to select between which pair. For instance, the scoop location and treble rolloff could be higher in one switch position and lower in the other.

[wolf1728]

Well it's nice to see all those replies.
Okay, the latest version of the mid-cut boost circuit is at the bottom of this posting.
It seems to me that the 5 to 10 portion would work in the reverse direction of the usual way that tone controls are wired.
Is there any resistor that should go in parallel with the right side capacitor?
I like the Dremel™ solution of creating a "no load" tone pot at position 5. I've made many "no-load" pots for my guitars by scraping away the graphite at the 9 to 10 position.

I'm not a big fan of "push-pull" pots either.
1) toggle switches are cheaper
2) toggle switches have a more positive "feel" than push-pull pots.
3) push-pull pots (as others have said) cannot fit in all guitars. (They won't fit in an SG for example).

By the way, I'm a big believer in guitar rewiring. Here's what I've done to some guitars

Well, I hope this thread will continue on a little bit longer.

[David Schwab]

By the way, I'm a big believer in guitar rewiring. Here's what I've done to some guitars

Is that first guitar an SG-2000? I always liked those, since Bill Nelson played one.

I used to do that stuff a lot. I do it a lot less these days.

Here's me in 1976, playing a '74 Ric 4001 bass.

Notice the extra knobs and switches!

It had a Hi-A (Bartolini) bridge pickup, and a Carvin neck pickup. It also had a Hi-A preamp. Eventually it had a third pickup added, a DiMarzio Model P.

[thumbs]

Speaking of loading, has anyone tried that mod where you jump the tone control off the center lug of the volume pot instead of the selector switch. It seems to help but I'd like to hear some other opinions on it.

[wolf1728]

David Schwab
When you asked about whether the guitar was an SG 2000, I immediately thought of the guitar underneath it - an SG Standard. Then I rethought and yes that first guitar is a Yamaha SBG 2000. (That's right an SBG). I bought it used and was trying to decide between that and a Gibson Les Paul. I thought it had better sustain than the Les Paul and that convinced me. From what I've read about it, the guitar is very solidly-built and I like the fact the neck runs through the body. Like the Les Paul, it weighs a ton (probably more than the Les Paul).
I see your Rickenbacker bass was seriously rewired. Although I've never owned a Rickenbacker guitar, I've always been impressed with the way they are manufactured. No, I don't visit their factory, but the look of a Rickenbacker is very impressive. They have the look of a well-engineered guitar. Yes, I know some companies such as Gibson go out of their way to make their guitars stained, painted and lacquered a zillion times but the look of a Rickenbacker is different than that.

[David Schwab]

David Schwab
When you asked about whether the guitar was an SG 2000, I immediately thought of the guitar underneath it - an SG Standard. Then I rethought and yes that first guitar is a Yamaha SBG 2000. (That's right an SBG). I bought it used and was trying to decide between that and a Gibson Les Paul. I thought it had better sustain than the Les Paul and that convinced me. From what I've read about it, the guitar is very solidly-built and I like the fact the neck runs through the body. Like the Les Paul, it weighs a ton (probably more than the Les Paul).

It was originally called an SG-2000.

It was introduced in 1976, and Yamaha contacted Carlos Santana shortly thereafter to see if he was interested in endorsing the instrument. He actually appeared on the cover of Guitar Player magazine in June of 1978 holding the SG2000, but the article explained that Santana actually redesigned and introduced many of the features on the original SG2000. According to Santana, the guitar was too light and didn’t resonate like he wanted. He recommended making the guitar heavier with thicker woods and installing a brass plate underneath, connected to the tailpiece (later patented as the Sustain Plate).

You also may notice that the SG prefix is very similar to a certain brand from one of the most popular U.S. builders today. When the SG Series from Yamaha became widespread in the early eighties, Gibson put a stop to it, and all Yamaha SG models were changed to SBG in the US.

Yamaha SG2000 - Premier Guitar

I see your Rickenbacker bass was seriously rewired. Although I've never owned a Rickenbacker guitar, I've always been impressed with the way they are manufactured. No, I don't visit their factory, but the look of a Rickenbacker is very impressive. They have the look of a well-engineered guitar. Yes, I know some companies such as Gibson go out of their way to make their guitars stained, painted and lacquered a zillion times but the look of a Rickenbacker is different than that.

Rics do have a classic design. I believe it was Roger Rossmeisl who designed the 4001. He also did those Coranados for Fender, which are not my favorite instruments!

I appreciate that Rickenbacker more-or-less keeps them true to the original, and although I love the tone of a Ric bass, I also wanted other tones, so that was my impetus for the mods. Plus some things needed upgrading, like the bridge. It looks nice, but was hard to adjust, so I replaced it with a Badass II when they came out. I also refretted the bass with larger and harder fret wire.

I still have it, and I'm currently in the process of restoring it, and painting it jetglo.