Category : Original composition (Performance)
Event : Kingfisher PubRockFest '08.
Category : Original composition (Performance)
Event : Kingfisher PubRockFest '08.
A video from Kingfisher PubRockFest '08, opening for Rachelle van Zanten.
Category : Build and Review
Review after the last mod
The 'Howler' is a two-tube-driven pre-amplifier, with a rhythm channel that goes from warm, fat clean tone to high-sustain overdrive, and a lead channel which pushes gain from a drier lead to a fuzz-like saturation.
In the initial version, when I hadn't figured out how to cancel the audio hum out completely, and was using smaller pots, the rhythm channel gave a bright, fat clean sound throughout the rhythm channel and a tri-amp sound on the lead channel. This wasn't as usable as the current configuration, but it was a different pre-amp altogether. It seemed ideal for use as a home-AV system pre-amp, as it stayed clean throughout the gain region on the rhythm channel.
Anyway, this new and improved pre-amp finds its place on top of a solid-state or tube amp and our latest test show us running a Laney 4X12 cab through a Laney 15 W head and the 'Howler' right before it.
Usually you can't get enough sound from the above setup without the 'Howler', but now it sounded "re-inforced" like with a boost pedal, and we did not lose sustain at all, like previously.
Technically, the pre-amp becomes extra-useful for guitarists that travel with their own 15-watt heads (Ibanez TubeScreamer, Vox NightTrain, etc.) to shows and look for a 2X12 or a 2X10 cab to retain the 'body' of the sound output. With the 'Howler', the 15 watt head gets just the boost it needs to go all-out out of 4X12s.
The Approach
Getting to the specifics, the idea started out as a foot-operated pre-amp pedal, and I saw a lot of designs posted online. The aim was to make something practical and useful, rather than just give a boost to the effects line. Also, without Home Depot, RadioShack, etc in India, finding parts to get this thing together was a task similar to building a working elevator out of a junkyard treasure-trove. So, I looked at some designs and the various mods that people had suggested, going through videos and schematics wherever available.
We found many pedals which did not meet our checklist for the kind of drive/distortion pedal we had in mind. 12AU7s were the most popular ones being employed, followed by some tubes that are seemingly impossible to get in India, like the 12AT7s and the 12AY7s. Matsumin's single-tube design seemed to be the base for most of the pedals, so we decided to keep the basics similar, and work more on the conditioning of the output sound. We were looking for a sustain-friendly, hi-gain overdrive that relied on the 'Attack' to decide when and how to break-up the sound and were looking for a two-channel operation to give it the usability of having a rhythm and lead tone on-the-fly.
The Design
I came up with the design in which I doubled the Matsumin single circuit although I wasn't sure of the filter and resistance values so I didn't carry them through directly. Also, I really wanted to see the effect of getting a warm tone out of the 12AU7 while unleashing gain through the 12AX7, so the values wouldn’t do anyway.
A dozen-odd combinations for the input capacitance for either stages, the variations on the 1- megohm input resistances and the pot-values were tried and this is what the final design looked like:
Schematic for the pre-final version. The pots were changed to 100k and the input resistance to the 12AX7 was reduced from 1 MOhm by paralleling it with a 690KOhm resistor. This gave us a smoother delivery and totally took away the possibility of channel switching with a lower volume on the Lead channel.
The Parts
The Housing
As mentioned earlier, access to power-tools and even metal-molding or milling machines is pretty difficult here. So I went with the old ‘wooden-box’ design.
Category : Original Composition
This was our third, and by far the most successful original composition ever. It won us Band Competitions at all the colleges in 2008-09, and was our audition entry that saw us performing at SAARANG-IITM in front of Opeth! Also, the Kingfisher Pubrockfest - those videos are here.
Category : Fusion Jamming
This was a late-night jam in the hostel with Lenin. He had a few steel glasses left over from the mess, and we up-turned one, filled a bit of water in one, and used the third just as it was. We also used a tooth-pick box for the hat sound.
The guitar was on a DADADG tuning as I had just been oiling the tuning pegs and they were being a bit stubborn.
The scale is Indian/Eastern with minor second intervals.
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