hammer.ampage.orgThe Hammer Files - AMPAGE - Tube Amps / Music Electronics

hammer.ampage.org 1 2 3 4 5 6 7 8 9 10 11 12 ↑ ↓ hammer Guitar pad 5/19/2010 12:12 AM Guitar_pad.mp3 Ethereal guitar sound made by plugging into a Craig Anderton Bi-Filter Follower, then into a PAiA Gator, then a Boss DM-3 clone modded with a hi-cut filter in the feedback path. The phasing effect is added digitally with Audacity, but everything up to that point is analog. hammer A trip back to the park - adventures in re-echo 1/30/2009 2:26 AM Re-echo.wma The Line 6 Echo Park comes with two inputs and outputs. While not true stereo, the unit allows for some interesting cross-recirculation and reprocessing possibilities. The soundclip illustrates two of the possibilities. It starts out with a short riff using the "reverse" program in the normal way. I have it panned 100% wet so you only hear the reverse. From there it switches to a re-echo whereby I plug into A, run A output back to B input, and send B output to the amp. You can hear a lovely shifting overlapping sound. Note as well that when you reverse what has already been reversed, you get it forwards again...sort of. Really interesting texture. The second half of the sample illustrates the same once, then twice, processing of the "sweep" program. This is a program in the Echo Park that imposes a kind of wah sweep on each iteration. You'll hear it normally (again, 100% wet to emphasize the sweep), and then reprocessed. Note the lovely rhythmic emphasis feel to it. Also note that I have simply hit one note to produce all that. Apologies for the buzzing. That's what you get when you record with single coils in front of a CRT monitor in a room with fluorescent lights. The fuzz is a Jack Orman Mos-Face; a variant of a Fuzz Face but with a mosfet transistor. hammer Envelope control of a Boss RPH-10 1/22/2009 1:51 AM RPH-10-all.png PH-2_2.png RPH-10_with_env.wma RPH-10-a.jpg I recently picked up an old Boss RPH-10 phaser. This is a terrific little unit that should be thought of as a more muscular version of the PH-2 phaser pedal. Both are 12-stage phasers with 8 swept stages and 4 fixed stages, and both use Boss's proprietary IR3109 quad OTA chips as well as companding to make the IR3109s behave. The PH-2 appears to have a 6-stage and 12-stage mode, where the RPH-10 has a 3rd mode that seems to have 10 stages but stagger the sweep of the two IR3109 chips in some manner. Where the PH-2 has the usual Rate, Depth and Resonance/Feedback controls, the RPH-10 adds a Manual offset control, not unlike what is in the BF-2 flanger. Just like the BF-2, the Manual and Depth complement each other. Several other features stand out in the RPH-10. First, it has dual feedback paths, which the PH-2 does not have. Second, it has a "polarity" switch which inverts the control voltage. Third, it has a patch point for control voltage which lets you feed the LFO out, or feed another control voltage in. With that option available, I went ahead and added an envelope follower to provide envelope control of phasing. It was a simple half-wave rectifier, based on the venerable Doctor Q,providing a gain of around 168 at max gain. I used a 10uf cap to smooth the envelope in parallel with a 47k resistor to keep the decay time modest. The resulting envelope voltage is fe through a 10k resistor to the junction of R82 and R58 in the RPH-10. Because the internal shell is already pre-machined to accommodate more controls than come with the stock RPH-10, I was able to use those holes to add a sensitivity control and a toggle to enable/disable the envelope input. All that remained was to pop a couple of suitable holes in the plastic panel, add some rub-on legending, and wire up the little daughter board. It all worked like a charm and I recorded some rather amateurish samples to show off what it does. They are strung end to end, and illustrate two of the modes in each polarity setting, ending with a combination of LFO and some envelope modulation over top to show off what you can do with two control sources. It provides a nice semi-periodicity that "humanizes" the sweep. I have to say that envelope control of phasing is a very nice thing to have, and the RPH-10 makes it easy. A more valuable unit now, IMHO. hammer Some Shin-Ei Hockey 6/23/2006 1:46 PM modded_fy-2.gif FY-2.mp3 I acquired a Shin-Ei FY-2 fuzz in 1992 or so. I had bought it for $20 from a second hand store, largely because it had a decent case and stompswitch and buying either of those where I was living at the time would have cost me at least $30. Having a naively lesser opinion of 60's fuzzes at the time, I ripped the circuit board out and built another circuit into the box. The original board sat around for a decade or more until someone finally posted information that let me reconnect the pots to it and fire it up. Boy was I glad I did. The thing is nasty, sick, fierce and all the other things you want a fuzz to be. It is also a little more maleable than one would think, and VERY easy to build. The unit uses 2SC536F transistors. The F-suffix indicates 536's with hfe values in the 180's to 240's or so. The transistors on mine were around 250, but the values on one I built from scratch were 220 and the difference appears to have no impact. The stock unit employs a passive mid-scoop filter between the fuzz-generating circuitry and output level control. While this injects the right amount of sinister tone (like a Superfuzz), it isn't always what you want. The scooping depends on passive loss through a 0.1uf cap. If you reduce the bleed through that cap to ground, you end up increasing the lower and upper mids and increasing the "body" of the sound. I inserted a 50k pot on mine (shown in the schematic) between the 0.1uf cap and ground. Alternatively, if the entire scoop circuit is bypassed and replaced with a fixed value resistor, you get the "full bandwidth" fuzz tone without any tone shapping. The MP3 file provides comparisons between two FY-2 units. The first is an original, and the second is a home-build clone. What you hear is (in order): - single note, original board, stock, minimum fuzz - single note, original board, stock, maximum fuzz - single note, original board, scoop bypassed with 33k resistor, minimum fuzz - single note, original board, scoop bypassed with 33k resistor, maximum fuzz - single note, clone, max fuzz, passive bleed through midscoop varied - A-chord, clone, max fuzz, passive bleed increased over chord - A-chord, clone, max fuzz, passive bleed decreased over chord All samples recorded with neck+bridge pickups directly into a Roland UA-30 USB interface. No other devices were involved. Though the volume level on the fuzz was set the same all the way through, there are some pretty substantial volume changes so don't crank it up too loud until you've heard the whole sample. hammer The Tangerine Peeler 10/12/2005 2:36 AM Tangerine_Peeler.gif This is a first attempt (October 2005) at a slightly more complex derivative of the classic Dan Armstrong Orange Squeezer OS compressor. The OS is much loved as a pretty transparent guitar compressor. The transparency is partly achieved by means of a low distortion solid-state "virtual" attenuator comprised of an 82k resistor and a 2N5457 FET. The use of an RC network between drain and gate helps to reduce distortion of the cell. Also helping to produce the transparency is an envelope follower with relatively fast attack and decay. Use of a FET as the control element further aids the speed of the unit. Like most guitar compressors, the OS uses a feed-back control path so that the envelope/control-signal is derived from the changed/changing signal (one whose dynamics have been altered). This enhances the "squish" that compressors normally achieve. Where the unit takes a slight left turn is in being able to select between feed-back OR feed-forward control. Feed-forward control is more often used in high-end limiters, and takes the control signal from a point *before* the dynamics were changed, this tends to result in the mo...