Brian May Treble Boost Question...

[zachomega]

Has anybody built one of the Brian May Treble Boosters built around the BC182L?  I just finished a Rangemaster last night and love it.  Is the Brian May Treble booster worth pursuing or what?

-Zach Omega

Schematic can be found at:
http://www.generalguitargadgets.com/index.php?option=content&task=view&id=119&Itemid=163

[tcobretti]

I have built 2, and I love them.  I built it with the BC182L, and frankly it makes very little difference what transistor you use.  A 5089 will sound just as good.

I built my second one with a switchable input cap, and I believe that the second one uses the Dragonfly layout that omits the 1k resistor after the 4n7 cap.  Omitting the 1k makes the whole thing louder and a little knarlier.

I gave the first one away and kept the one without the 1k resistor.

I recommend that you omit an output volume control as it goes against the spirit of the pedal.

[zachomega]

I have BC182L and 2n5089's...So I'll probably go with the BC182L.  Both transistors have pretty good noise specs though. 

You anticipated one of my questions...So no volume control?  Is the thing essentially at unity with the 6.8k collector load? 

Hmm...no 1k resistor. 

-Zach Omega

I have built 2, and I love them.  I built it with the BC182L, and frankly it makes very little difference what transistor you use.  A 5089 will sound just as good.

I built my second one with a switchable input cap, and I believe that the second one uses the Dragonfly layout that omits the 1k resistor after the 4n7 cap.  Omitting the 1k makes the whole thing louder and a little knarlier.

I gave the first one away and kept the one without the 1k resistor.

I recommend that you omit an output volume control as it goes against the spirit of the pedal.

[MetalGod]

yes, the BM treble booster is VERY LOUD - run it into the bass channel of a plexi Marshall and run for cover 

[zachomega]

Hmm...Now that makes me wonder if I should have a volume control.  I like loud...sometimes, but I also like unity. 

-Zach Omega

yes, the BM treble booster is VERY LOUD - run it into the bass channel of a plexi Marshall and run for cover 

[tcobretti]

The primary use for a booster is to overdrive an amp's clean channel.  If you want control over how much you overdrive it, then add a volume control.  Boosters can sound weird with different amps, and can make your computer's speakers sound like they are going to explode.  In fact, they can blow your computer speakers, which I have done as well.

One of the sweetest booster applications I have heard is the BMTB thru the clean channel of my friend's JCM900.  It was undeniably awesome, and I hated his amp!

[Barcode80]

i built one from dragonfly's layout, added 1M pulldowns for popping, and added a volume control at the output. IT SOUNDS AWESOME! great for lead work. I wish i had taken build pics before i gave it away...

[zachomega]

OKay...So if I want a volume control (and I think I do) do I want to vary the collector resistor with a 10k pot or keep the 6.8k resistor and use a 100k pot taken from the output? 

I'd imagine the 6.8k and 10k resistors would throw the collector voltage a bit. 

-Zach Omega

[tcobretti]

The one I built with a volume control had the collector/10k option.

[zachomega]

And all was good?

-Zach Omega

The one I built with a volume control had the collector/10k option.

[zachomega]

Also, did you guys use that 120k resistor on the input?  Seems awfully low for just a pull down resistor.  I'd imagine it to have some tonal effect on the sound...for better or for worse.

-Zach Omega

[tcobretti]

The collector/10kpot worked well.

I built mine exactly like the schematic.

[zachomega]

What about that 2.4k resistor?  That doesn't appear to be a standard value and I'm not ordering just 1 resistor.  2.2 or 2.7 k?

-Zach Omega

The collector/10kpot worked well.

I built mine exactly like the schematic.

[Barcode80]

i put an extra 1m at the beginning for pulldown. also, i just put a volume pot on the main output

out--->pot lug 3

          pot lug 2---> output

          pot lug 1---> ground

[zachomega]

It shouldn't need an extra 1 meg at the front of the circuit...but will need one at the output without a volume control there. 

Also, I worked out the 2.4k with 2 1.2k resistors.  Don't know why I didn't think of that at first.

Still debating what to use for the collector.

Can anybody say how much this differs from the conventional rangemaster? 

-Zach Omega

i put an extra 1m at the beginning for pulldown. also, i just put a volume pot on the main output

out--->pot lug 3

          pot lug 2---> output

          pot lug 1---> ground

[tcobretti]

Honestly, I've never built a rangemaster because I like the BMTB so much.  I suspect that it is higher gain (especially if you leave out the 1k resistor), lower noise, and possibly more temperature stable.

[Ronsonic]

I build a pedal for people that started off as a BMTB clone and evolved from there.

A 2.2k resistor works fine in place of the 2k4.

I prefer a 100K level control at the output. That way our little transistor is running full gain all the time. A little more funk to the sound. I sure understand running one of these completely cranked, but it becomes a more versatile  and useful pedal with the control. Punch any overdrive pedal with one and it changes everything.

The BC107 is more consistently quiet for me than the BC182 and I'm pretty sure I prefer the sound as being a bit more complex.

Great pedal for cutting through the mix with a neck pickup.

Build 'em and play.

Ron

[Pushtone]

I built the GGG BMTB project with BC128L

Its very loud indeed. Not having a volume control would be ampocide. 

I think I'll just plug in my RM and BMTB together now and see what the differences are.
Give me a minute...

...
...

Guitar: Ibanez Art Core 335 copy (kinda warm/dark PUP)
Amps: Solid State Roland 408, Tube AX84 High Octane (JMC800 pre w/ 2 6V6 Power tubes)

Tone:
RM distortion is a little sweeter than BMTB, but they are close. I got the tranny from SB specifically marked for the GeoFex RM project.
It's a metal can marked 2N1305. Temp in my basement is around 65deg tonight. These days I know to buy CV7212s in the diystompboxes store.
RM drops the lows, boosts the highs (duh). BMTB (stock GGG) retains more bass frequencies, but does the highs like the RM.
One might say the BMTB is slightly more full-range. The bass freq sound less distorted than the highs too.
This is the biggest difference between the two to me. And limiting the bass response of the BMTB to be more like the RM would be the way to go.

Hiss & Noise:
RM adds a lot of hiss (again, duh). BMTB is much, much less hissy. But there is a buzz in mine, but that might be poor wiring/grounding
so let just ignore it. As far as hiss goes... BMTB gets the nod. Much quieter, and in a treble boost, that's important.

Solid State Amp:
I was surprised that both sounded just OK with the solid state amp.
Not bad, but not good. Kinda the buzz saw sound.

Tube Amp:
With the tube amp all is good. I have a home built ax84 High Octane with
two 6v6 power tubes and tube recto. It sounds very good on its own.
Adding a TB is like kicking in a lead channel.
Both boosters make chords sound highly textured.

Sonically, it dominates the upper-mid band and when recording with a treble boost I find IT has to be the center of attention,
hence my opinion its a soloing only type pedal. Competes with the vocals too much to use it all the time.

And finally,
After a long jam session, both pedals will have yer ears ringinggggggggggggggggg.

With all that I like the sound of the AMZ mini booster better. Add the input cap mod and you have a treble booster without any hiss.
But it does sound more gritty and the RM/BMTB more zingy. 

Let me know if you would like any specific comparisons.
They sound too close for sound clips. A zing vs. a zong.

Bottom line for me...
BMTB=less hiss, same sound more or less.

[Pushtone]

Great pedal for cutting through the mix with a neck pickup.

Ron

Yes, good point. I used to kick in an EQ with the bass rolled off when I wanted to use my neck PUP.

The treble boosters do the same trick while imparting much more personality into the tone.

I use the AMZ MosFET with the neck PUP too, for clean.

[zachomega]

Awesome review! 

I've been lucky in that my Rangemaster isn't particularly hissy.  I used a 2sb175 with low leakage (around 50-70 microamps) and a gain around 75.  It does have some hiss, but as I said, nothing unbearable and with the gain control down, it is really not bad at all. 

I suppose at worst, if I strongly dislike one over the other, I can always sell it off cheap or give it away as a stocking stuffer. 

I think I'm going to go with the 10k pot for level.  Thanks for all of your input guys!  You've been nothing but amazingly helpful!

-Zach Omega

I built the GGG BMTB project with BC128L

Its very loud indeed. Not having a volume control would be ampocide. 

I think I'll just plug in my RM and BMTB together now and see what the differences are.
Give me a minute...

...
...

Guitar: Ibanez Art Core 335 copy (kinda warm/dark PUP)
Amps: Solid State Roland 408, Tube AX84 High Octane (JMC800 pre w/ 2 6V6 Power tubes)

Tone:
RM distortion is a little sweeter than BMTB, but they are close. I got the tranny from SB specifically marked for the GeoFex RM project.
It's a metal can marked 2N1305. Temp in my basement is around 65deg tonight. These days I know to buy CV7212s in the diystompboxes store.
RM drops the lows, boosts the highs (duh). BMTB (stock GGG) retains more bass frequencies, but does the highs like the RM.
One might say the BMTB is slightly more full-range. The bass freq sound less distorted than the highs too.
This is the biggest difference between the two to me. And limiting the bass response of the BMTB to be more like the RM would be the way to go.

Hiss & Noise:
RM adds a lot of hiss (again, duh). BMTB is much, much less hissy. But there is a buzz in mine, but that might be poor wiring/grounding
so let just ignore it. As far as hiss goes... BMTB gets the nod. Much quieter, and in a treble boost, that's important.

Solid State Amp:
I was surprised that both sounded just OK with the solid state amp.
Not bad, but not good. Kinda the buzz saw sound.

Tube Amp:
With the tube amp all is good. I have a home built ax84 High Octane with
two 6v6 power tubes and tube recto. It sounds very good on its own.
Adding a TB is like kicking in a lead channel.
Both boosters make chords sound highly textured.

Sonically, it dominates the upper-mid band and when recording with a treble boost I find IT has to be the center of attention,
hence my opinion its a soloing only type pedal. Competes with the vocals too much to use it all the time.

And finally,
After a long jam session, both pedals will have yer ears ringinggggggggggggggggg.

With all that I like the sound of the AMZ mini booster better. Add the input cap mod and you have a treble booster without any hiss.
But it does sound more gritty and the RM/BMTB more zingy. 

Let me know if you would like any specific comparisons.
They sound too close for sound clips. A zing vs. a zong.

Bottom line for me...
BMTB=less hiss, same sound more or less.