The 51-Filthy Amplifier
Current Build Time 1-3 Weeks.
ALL AMP SALES ARE FINAL.
A 300watt Class D amplifier based on our 51-Filthy preamp. Orders are open NOW!! Build Time is typically 2 weeks.
Introducing our first official high gain amplifier. Featuring our 51-Filthy with two extra gain modes as the preamp section, a boost circuit tailored specifically for this amp and our own proprietary power amp input section. We've made it dead-simple to get the tone in your head out to people's ears.
Boost Section
Boost: Controls the amount of Gain Boost in the signal. Minimum on the control will add a small amount of gain and aggression. Maximum on the control will give you noticeably more. There is no wrong setting though and the entire range has been specifically tuned for this amp.
Tone: This controls the upper mids content of the Boost circuit. Adjust this to match your guitar or crank it to max to get some major chainsaw action.
Boost Bypass: This should be obvious, but it turns the Boost section on and off.
Preamp Section
Pre: This is the pregain control. It could also be referred to as just the Gain or even Distortion. While you may picture this amp as being a one-note-pony, it can actually be surprisingly versatile. On the lower end of the dial you will find a light crunchy breakup. A full-on crunch is typical around Noon and above that is where the saturation starts to happen. Going further up, you will get close to maximum saturation at about 3oclock, with the maximum being at maximum. Keep in mind that just like a tube amp, the highest settings will seriously saturate the signal and you will lose some of the apparent "tightness". It's also worth mentioning that these are starting points and not exactly where you will find the setting you're looking for, simply due to the huge variety in pickups, string gauge, playing style, etc.
Treble: The classic treble control. The higher you go, the brighter and more attack you'll find. Depending on your speaker and the other settings, going too high can give you what's referred to as "fizz" but certain amounts of this are typically what you want to cut through in a mix. Start low and keep turning it up until you hear the sound you want.
Mid: This could also safely be called a "shape control" as it does the most serious shaping of the overall tone. Take things all the way from a totally scooped 90's solid state head, to the upper mid presence of a 5150, to the warmth of an old Marshall. There's no wrong setting. Just close your eyes and start turning!
Bass: We kept a fairly narrow range on this control to avoid what we would consider "bad" settings. This amp isn't about huge booming low end, it's about angry high gain tones. Looking for massive wall destroying low end? check out the SPEC-Defier Amplifier.
Gain Mode: On top of the original/stock sound of the 51-Filthy (Tight setting) there is also the Chunk Mode which gives you a bit more gain and a lower bass rolloff for more, you guessed it, chunk, as well as the Phat Mode which adds even more gain and low end.
Post: The Post Gain control is also just called the Volume on an amp that doesn't feature a Master Volume control. What it actually is, is the preamp section volume control. If you're running a noise gate in the effects loop and finding it's clamping too hard, it's better to turn this volume up to a higher level.
Effects Loop Section
Send: This is the buffered preamp signal output. It can be used to record directly without the power amp or to send to any effects you're using in the loop.
Return: This is the buffered input of the power amplifier section. It can also be used to amplify external preamps but typically used to connect the other side of your effects that you're using in the effects loop.
Power Amplifier Section
Presence: This is the same in function to what you would find on any amplifier, but with a handful of differences. Rather than altering the negative feedback loop, this Presence control is a combination of a passive treble bleed and an active eq.
Resonance: This is also known as Depth depending on what part of the world you live in. It is essentially a low end control for dialing in the thickness/"meat" of your tone. We fine tuned it to help capture some of the "feel" of a thumping 4x12 cab at low volumes. Crank it up and hear how massive your tone gets!
Mids -/+: This is what sets our power amp apart from others. Never again do you have to settle for whatever midrange frequencies are most present in the power amp you've plugged into. Turning this control to Noon will bypass the effect. To the left will cut whatever frequency the Shape control is set to. To the right boosts it. High mids will give you additional presence when boosted. Low mids being cut will clear up any honk/cardboard tone.
Shape: This is the sweep of the range on the Mids -/+ control. Frequency ranges are detailed in the Bull/Beaver Switch section. It is also bypassed when the Mids -/+ is at Noon.
Bull/Beaver: This two position toggle switch selects between two independent frequency ranges. Beaver Mode sets the Shape control to a range of 400-800hz. Bull Mode sets the Shape control to a range of 1500-2500hz.
Master: The Master Volume controls the overall volume of the entire amplifier. Since the power amplifier section is Class D, the tone is the EXACT SAME at every setting. This allows you to have the same tones at bedroom level volumes. Any and all tonal changes you hear at loud volumes you're hearing are from the speakers being pushed, the resonance of the cabinet, the interaction between the two and more.
Output Section:
Wattage: The 51-Filthy Amplifier features a maintenance free 300Watt Class D power amplifier section. No tubes to replace, no day to day tonal changes. The general rule of thumb with Class D is that the power is halved when doubling the impedance. This isn't totally set in stone, especially when considering the audible output and not just numbers. For example, here at the shop we've achieved 125db from the 60watt Lindworm with conservative settings.
300watts- 4ohm load
150watts- 8ohm load
75watts- 16ohm load
No special switching needed to change cab impedance, but it MUST be powered OFF when plugging or unplugging a speaker cabinet.
The typical 2x12 will be 8ohms and the typical 4x12 will be either 8 or 16ohm. These can be safely run in parallel to achieve more power and there are tons of impedance calculators out there. Who doesn't love the thought of 300watts screaming out of a pair of 4x12's?
External Power Section
9VDC Out: Two 9 volt outputs can be found on the rear of the amp. These can supply up to 100mA each to power external pedals. Want to run your favorite noise gate with just a couple short cables? You can do that!
Power
The 51-Filthy Amplifier accepts universal mains and can be run at 100-240volts.
Size/Format
The 51-Filthy Amplifier is housed in a 3U half width rack enclosure. You can omit the rack hardware if you plan to put it on top of your speaker cab and save a few bucks. It is approximately 9"x8"x5.5"
Why Not?
"Why not add a noise gate?" you may be asking. There are two main reasons. First, we feel its a waste of both our money and yours! The ONE thing people say about built in noise gates is "it's okay but I just use the one I already had". Then there's the fact that if we had a worthwhile replacement for the Hades Gate, it would have existed long before any amps were in development!
"Why not a full width rack enclosure?" There is literally only one reason for this: The full width parts won't fit in our UV printer. Airis Effects is still after over a decade, a one-man operation so everything is produced in smaller batches. In order to be able to offer any sort of different format, the initial investment as well as the MUCH higher final selling price just isn't feasible at this time without some sort of Mark Cuban style investment of capital.