Rangemaster Variant...will it work?

[phillip]

Here's a variant of the Rangemaster, based on Keeley's Java Boost...sans the trimpots, that I was going to build for a whole lot less than one could be bought for.  The input capacitor switching that he uses in the Java isn't shown in the schematic so I added a swiching setup that I think will work...



The other parts of the circuit, like the tone control, will work...my concern is the input capacitor switching.  The switch is a 3-position SPDT on-off-on.  I put a 1M pulldown resistor on the loose end of the 0.047uF capacitor to keep it from popping when the switch is flipped into that position.  Will that resistor perform that function?

BTW...what kind of amps are Rangemasters supposed to "overdrive"?  I never could get a Rangemaster to overdrive my Fender Twin...

TIA!
Phillip

[Fret Wire]

I always though it was voiced for humbuckers and bassman/early marshall type amps. A twin is a terminally clean amp. Loud as hell, but not an overdrive machine. Even worse in the clean dept. if it's the higher wattage ultra-linear transformer model.

[brian wenz]

Hello Hello Phillip--
    Stock Rangemasters  [germanium] sound GREAT through English tube amps like Vox AC30 and Marshalls  [ they matched up to those amps 'cuz back then the Vox and Marshall were some of the only ones around..]  I think Rory Gallagher used a Hawk booster through his Fender tweed Bassman sometimes instead of the RM through a Vox.  
My treble boosters [both germ and si]  sound very good through  class-A  tube amps with EL-84 power tubes and  class AB tube amps with EL-34 tubes.   Master volume controls help things to distort nicely, too.
 Fender amps [Twins, Pro Rev., Vibrolux, Super Rev., etc.] from the 60's and 70's  are NOT a good match with  a RM.
Brian.

[BD13UK]

In the late 60's I used a Rangemaster thru an AC30, that and the FF plus Tonebender was about all that was available, I tried using the RM thru Fenders with little success  and the hiss thru the Marshalls was unbearable, Rory Gallaher used to cover his RM in tinfoil to try and block out radio and taxicab signals but it wasn't very effective.

[petemoore]

Awesome post !!! I'm a fan of the past. I like reading personal experience  excerpts from individuals...What were you up to in those days...late 60's?...you had cloudy and sunny days back then?...I was just a young kid, in Louisiana, and then Pakistan back then..I think I heard about Woodstock and JH, JJ, JM, and all the Zep etc. about one decade later.
 Since then the bushes have Really grown up, it's very hard to see much past the front lawn anymore...

[bwanasonic]

Basically you want an amp that is on the verge of breaking up or already a bit overdriven and EQ'd slightly dark. Doesn't describe a Twin very well, does it :wink:

Kerry M.

[puretube]

you may want another 1M from the node of the 2 caps (0.01uF) to gnd...

[Peter Snowberg]

I would add the resistor Puretube just mentioned, but I would make both resistors ~5M rather than 1M.

Take care,
-Peter

[AL]

Yep Yep i agree Twin's are very clean amps. Great amps but you need an overdrive.

Phillip, have you tried jumping the channels together to see if you can get a semi-master volume on your twin? Plug your guitar into the Normal (left) channel plug 1, run a jumper from Normal channel plug 2 over to middle (vibrato?) channel, plug 1.  This will give you a few more knobs to play with and you can crank the volume on the second channel and run your Normal channel at a lower volume to (hopefully) get a little overdrive.  I'm not sure how good this is for the amp but it sounds great with my bassman.

AL

[puretube]

Peter: look at the R from base to ground: 6k8;
usually I recommend 4M7, too - since many people have problems
finding 10M - but in this case, even 100k would be ok
(? or am I wrong, since there is no bypass-switch in this box ?)

[phillip]

Whoops...that 6K8 is supposed to be 68K.  Minor typo in the schematic.

My Twin Amp is one of the '94 "Evil Twins," which has two channels.  Channel one is divided into two parts...clean and "vintage drive."  Channel two is the full tube overdrive, which is pretty darn aggressive...the real tube screamer

I'll add the resistor to the connection between the two 0.01uF capacitors...I overlooked that point as a potential popper.

The circuit will have true bypass, I just didn't show it on the schematic to keep it fairly small for posting

Phillip

[Peter Snowberg]

6K8 :lol: Hehehe, I didn't see that.

I'm hopelessly stuck in FETland.

6K8???  :? (scratches his head)

Take care,
-Peter