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"Brian May Booster" almost up at GEO


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10/8/2000 3:11 PM
R.G.
"Brian May Booster" almost up at GEO
Thanks to Stan Cotey, who provided what is supposed to be a tracing of the real thing! I'm going to post Stan's picture there...  
 
I say going to because my host has some kind of server error that won't upload the actual picture file, although it uploaded the announcement page just fine! As soon as they get the bug fixed, the schemo will appear.
 
10/8/2000 3:51 PM
Gus

R.G this is the "real" one not the Guild? Thanks if it is Stan, R.G.  
I have been looking for this for friends that are Brian May fans and are not happy with the guild sound.
 
10/8/2000 4:31 PM
R.G.
It's there now! and some analysis
According to Stan, this is a tracing of the real thing.  
 
Notice the huge similarity to the Dallas Rangemaster. It's a single bipolar gain stage, with the bass cut done by the small input capacitor. The only significant differences from the DR I can see at a casual inspection are:  
 
- silicon transistor; makes for much better stability and frequency response, probably less hiss as well. May not give the same kind of soft squashing that the DR does, though. Have to check and see in some more in-depth analysis.  
- no variable output. The output is fixed by the choice of the collector resistor. This does away with the boost knob's crackle, but also with the adjustability. I suspect the just selected the value that Brian likes and subbed in a fixed resistor.  
- a 1K/1nF treble rolloff at the base-emitter junction. This is probably to tame some hiss. The DR's germanium was proably hissier than the 182L.  
Notice that the actual treble rolloff is affected by the value of the base-emitter internal resistance in parallel with the 1K. This internal resistance is current sensitive, and fairly low, so the actual rolloff point is higher than the 1K/1nF would calculate to.  
 
- a real, no fooling pulldown resistor at the input. This is a bit of an oddity with no switching shown, but maybe that part was just left out, or provided by an external switching setup.  
 
I'm working on a tech paper comparing the Dallas Rangemaster, this Brian May Booster, and the Guild "Brian May Booster" that I also have the circuit for.  
 
You are dead right, Gus - many thanks to Stan!!
 
10/8/2000 4:46 PM
Gus

R.G. it looks like the input Z is lower and the in cap lower so it looks to be more of a trele boost than the RM. FWIW I have built NP Si rangemasters for friends with a bias pot and resistor instead of the 470k (1meg 220k) lets one tune the distortion/gain to taste. Thanks again STAN AND R.G.
 
10/18/2000 11:27 AM
AvdHeijden
Not sure it's the real thing!
I'm not sure it's the real thing. Brian has used at least 4 different treble boosters over the years. From http://www.jackfunk.net/equipment.html:  
 
"Brian's famous sound could not be totally achieved without, yet another, home/custom made pieces of equipment. Brian has used a treble booster ever since his early days of playing gigs. Brian's first treble booster was a Dallas Rangemaster, which was left at a gig, and lost right after the Queen II album came out. His second treble booster, (get ready for this... again) was made for him by his father. The third and probably most famous of all the treble boosters Brian has used was the unit that Pete Cornish (pictured above) made for Brian in late 1975. Cornish's design would later, supposedly, become challenged by Guild, who in 1993 made some similar copies of, to coincide with their Brian May Signature guitar line. Never the less, it was Pete Cornish's treble booster that really propelled Brian's sound into what we know it to be today, that is as of 1998. In 1998, Greg Fryer, most notably known for refurbishing and replicating The Red Special for Brian, created Brian a copy of the Pete Cornish treble booster as well. Greg refined his version with various circuitry modifications to cut down on noise. The new Fryer unit is Brian's newest and most favored choice of all the treble boosters."  
 
I doubt the fact that the Cornish one propelled Brian's sound into what we know it to be today, but that's not my point.  
I've seen pictures of the Cornish treble booster (there's one on the site I quoted). This one has a knob (for amount of boost), so the scheme can't be this one. The Fryer one is fairly new, I also have pictures of this one and it also has a knob.  
This means the scheme can only be the one that Brians father made. I never saw this one, so it's possible. But when I realise he only used this one from, let's say, 1972-1973? 'til 1975, I really doubt the fact that this is the real scheme. Maybe I can contact Stan Cotey (who provided the scheme) about this, but I don't have his e-mail address.  
 
If you wanna know more about Brian's equipment, go to http://www.redspecial.com. It's in Japanese, but it has some text in English. The guy even contacted Pete Cornish and Greg Fryer!! It also has a lot of great pictures. Even the rare Foxx Foot Phaser (Brian used it) can be seen.  
R.G., If you're going to compare the treble boosters, you might wanna contact Shiro, who made this site. He also compared some treble boosters, but his results are reported in Japanese.  
 
AvdHeijden  
 
PS: I'm pretty sure Brian NEVER used the Guild treble booster (btw: there are 2 different versions of this one. One from 1986 and another from 1993. I have pics of both.)
 
10/18/2000 2:59 PM
R.G.
I'm not sure it's the real thing, either, but Stan says it is. Maybe it's one of the real things, which varies, which seems to be what you are saying. The world is open to a number of paths to nirvana.  
 
It's a bad idea in general to expect anyone's "magic box" to make your playing sound like them. I'm actually a believer in the "tone comes out of your fingertips" school myself.  
 
I'll wander around in my usual fog; if I can get to Shiro, I will. Thanks for the tips, and I hope your investigations shed more light on this for us.
 
10/18/2000 11:03 PM
Frank Clarke

Freyer does seem to sell Brian May Treble Boosters,  
http://homepage1.nifty.com/soulbrother/others/bmtb.jpg  
 
and he did take Brian's guitar to bits, so this may be the Brian-approved current design.  
 
According to Fryer the Red Special used to have a built-in distortion unit with external knob.  
 
http://www.queen-rocks.com/~unicorn/greg_fryer.htm  
 
Has anyone got the schematic that makes me sound like Brian May?
 

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