Treble Boosters

[col]

Over the weekend in an attempt to directly compare a few boosters I made a pedal up with both Sparkle Boost and Brian May Treble Booster circuits selectable by a DPDT toggle switch. My main purpose was to find a Si version which compares to my Ge Rangemaster Clone which I find invaluable for solo boosts and slightly driving my amp when gigging, but unfortunately it is not temperature stable. I don't know how I'd cope without one now as I find it the most useful pedal I have ever had apart from a distortion/fuzz.
When compared to my Rangemaster clone and each other both Si circuits sound very different. I had made the two Si circuits some time ago but never boxed them up so I had not been able to do a direct comparative test before. What amazed me even through my practice amp was the recognizeable tones I was able to achieve. The Brian May and Sparkleboost enabled me to get that early Black Sabbath and Deep Purple tone effortlessly, which is quite suprising as I'd always believed that Tony Iommi had used a modified Rangemaster. The sparkleboost is VERY loud and can be used to give a mild overdriven sound by turning the drive control all the way up. Both considerably 'thicken' up the sound when on and it sounds rather dull without one when it's turned back off. Strange as I'd never thought that before!
I have made a couple of other treble boosters which I used before I built the Rangemaster clone. One I used a lot was from one of R A Penfold's books which had been great for live work but it crackled noticably when I tried to record with it. I know that some other pedals like this suffer in this way.
My band isn't practising for a couple of weeks so I won't get to try the new build in a band situation until then, but even though I don't think I'll replace my Ge box but I'll probably end up adding the new one to my permanent pedal line and maybe leave it switched on for some songs. I'll just have to wait and see.
I'd like to thank Dragonfly for posting the sparkleboost and everyone who helps to develop items like this. Without them we'd be stuck with whatever suppliers wanted to put out and there would be no room for development of this type of circuit.

[Dragonfly]

Nice review...id love to hear your thoughts once you get them into a band situation !

makes me want to build the BMTB !

andy

[brian wenz]

Hello Hello--
     Do a search for "piggy backed transistors".   Somewhere on this site is a great build for a Rangemaster-style  TB that uses two silicon trannys  wired together "piggy-back" style.  I built mine with a few mods and it's very stable with good, warm tone.
Brett.....where are you??!
Brian.

[brian wenz]

Hello Hello Again--
    Go to Marcos-Munkey's  site and look for Wil's  "Rangepig" schematic.
Brian.

[Ben N]

Like a Darlington?  (I have some MPSA13s lying around...)

[brian wenz]

Hello Hello--
    Nope, not like a darlington.  Piggybacked trannys lower the hfe so you get a warmer, spongier tone.  Check out the schematic for the Rangepig to see how they are wired...
Brian.

[Ben N]

Hmmm.  Munky's site appears to have vamoosed.  

[col]

I fianally got the chance to use them all in a live band practice situation and set them up with the Brian May/Sparkleboost and rangeblaster in front of the rest of the pedals which for most of the practice consisted of a three knob Foxey Lady clone, a boss chorus and a dual op-amp buffer. I played an Epiphone SG fitted with a super distortion pick up in the bridge position through the pedals into a Laney AOR50 valve amp and a Laney 4x12 cab. The treble boosters were used for solo boosts and for some clean intros.
When played without the rest of the band all three sound very different and all improve the quality of the sound considerably, although not noticably by as much as playing through my transistor practice amp.
In the actual band playing situation the differences between them was much less noticable with the exeption of the sparkleboost which cuts through more than the other two but can sound a bit harsh if the gain is up too much. The  Brian May and the Rangeblaster both sound very similar but the rangemaster can have much more gain when turned up full and it also has a slightly better sound, but that might just be because I expected it to! Ge MOJO?
At the end of the practice all I could gather was that all 3 pedals produced excellent results and all would do the job expected of them. The rangeblaster and the sparkleboost have more potential as they have the ability to produce more gain, but the Brian May is an excellent sounding circuit in it's own right. The sparkleboost can also be used to give a mild drive with gain at max and it can really cut through the rest of the band even when using heavily distorted humbuckers which could be VERY useful in a live situation, especially when playing the type of punk we do with a psychotic drummer and bass and another guitar to compete with through a backline of dubious origins.
I hope this is useful to people trying to decide what booster to make. They are very simple circuits so it might be worth making a few boards up and trying them all.
This was also the first time I'd tried a buffer and I'd recommend one if you are using more than a few pedals. It DOES make a difference, either at the front or end of your chain.

Col