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This content overlaps some of my previous messages, but adds some new detail and information. There seems to be enough interest in getting controllable, genuine cranked tube-amp sound without blasting, to warrant this additional detail. (Several interested people have emailed me directly.) I'm recommending not only an easy, future redesign of a multieffects processor to accomplish this Holy Grail of cranked amp tone on tap, but also practical ways to use existing equipment to get this control, in the interim.

Getting the absolute best tube amp tone is not necessarily the best, most practical goal. That would require a wall of amps and 8x12 refrigerator cabinets, and a sturdy recording studio located deep underground, far from fault lines. Rather, this rig design offers a reasonably good cranked amp tone, with programmable input level and eq, a power tube and speaker, and then a final programmable output level and eq stage.

Effects are important. But cranked tube amp tone is a *religion*. The problems of getting and controlling basic tube amp tone need much more attention from the programmable guitar processor companies -- from "effects" designers. Particularly, all the gear designers need to think of vastly better ways to *combine* top-notch effects processing with top-notch tube amp equipment. Putting top-notch effects in front of a top-notch tube amp is, for most potential guitarists, a poor way of combining effects and tube amps, for the following reasons:

o The amp tone is directly tied to the overall volume level in the room. More than anything, most guitarists most of the time want 100 watt cranked tube-amp tone at half-a-watt volume levels.

o There's a strong need for programmable control over the overall level of a tone, whether a clean tube amp or a cranked, saturated tube amp. Currently, clean tube amp tones always have to be quieter than saturated tube amp tones.

o There's a strong need for programmable processing *after* the basic tone of the saturated tube amp. In a studio, the mixer provides a final level control, a final eq, and a final effects loop for echo and reverb. In a studio, you *always* have isolation of the loud tube amp, a level control after the tube amp, eq after the tube amp, and an effects loop after the tube amp. Guitar amps pretend to be complete in themselves, but this is an illusion. A guitar amp is not complete without a loud room to play in, a microphone, and a mixing board.

For clarity, I specify particular models of equipment. But my philosophy is that "any decent" guitar, amp, speaker, and effects unit can sound great when configured properly. A speaker isolation cabinet offers a very powerful "no-compromise" compromise between total effects processing and total amp tone. While speaker isolation cabinets are the foundation of my approach, this approach also works very well with traditional big amps and cabinets in the loop, as well as attenuators and inductive loads.

If Digitech combines top-notch effects with a well-thought-out configuration of a power tube and speaker isolation cabinet, every guitarist would want to buy such a system -- particularly the huge market of guitarists who usually don't want a blasting amp, but want the dynamics of a genuine saturating tube amp. I've put together such a configuration, and the resulting control over both effects and cranked tube amp tone is a dream come true. Such a system would sound so great in the store, at any volume, lines would form to use it. It would combine the best effects you've heard, with good, controllable cranked tube amp tones. The amp would not have the benefit of a large, loud speaker cabinet, but it would have programmable level and eq both before and after the scaled-down speaker isolation cabinet, so it would still sound excellent.

I have designed two systems: an ideal guitar rig using *presently available* mass-produced gear, and an ideal rig that could be produced by repackaging existing gear. I also have a solution for people who already have a single 2101 processor, and to suggest a variety of gear with the central theme of genuine cranked tube-amp tone at vanishingly low room noise levels.

Processing chain for an almost ideal guitar rig using *presently available* mass-produced gear:

o Digitech 2112 (or 2101) guitar multieffects processor (use for distortion and eq-type and moderate effects)
o Kendrick 5-watt combo tube amp or Laney 15 watt combo tube amp
o Demeter speaker isolation cabinet, or Micro Room small spk iso cab
o 25-watt Celestion greenback speaker, or 6" speaker in the Micro Room
o Shure SM57 dynamic mic, or a condenser mic that can take loudness
o Radio Shack inline XLR to 1/4" adapter
o Digitech 2112 (or 2101) guitar multieffects processor (use for post-amp level, eq, delay-derived effects)
o Foot controller pedal - to simultaneously switch the pre-amp and post-amp effects units

This is expensive and slightly complicated using current gear. It would be much more ergonomic if Digitech designed an all-in-one unit. But you cannot argue with the Basic Tone that this system produces, because it literally contains a genuine cranked tube amp, with saturating power tubes directly driving a guitar speaker, with no inductive load, emulator, or simulator.

Any approach other than this, any approach that removes any of these stages, will not be able to combine top-notch tone, low room noise level, and *full* control of the level of the tube amp, independently of power tube saturation level.

An ideal rig that could be produced by repackaging existing gear.

This listing is the same complete list of stages as I posted a week ago, except it provides both an inductive load and speaker isolation cabinet.

o Wah, compression, phaser, distortion, eq, level (effects that don't muddy the power tube saturation)
o 6V6 power tube in Class A configuration (5 watts)
o Inductive load
o Additional alternative to inductive load: speaker isolation cabinet, guitar speaker, and mic
o Level, eq, flanger, chorus, echo, reverb (effects that would muddy the power tube saturation)
o 100 watt solid-state power amp
o Full-range monitor speaker

One way this should be packaged is as one large box, like ART's T28-100 Attack Module. Instead of a 2x12 arrangement of guitar speakers, it would have to contain both the speaker isolation cabinet plus the full-range final monitor speaker. This could be too heavy, and it's better if you can stick the speaker isolation cabinet in a closet. The iso cab leaks low bass, which makes it hard to hear just the *final* tone.

As much as I'd like an all-in-one unit, it might be better to keep the speaker isolation box as a separate unit. But a *variety* of packaging options should be available. I hope that there are hundreds of these products to choose from. It's a vastly advanced approach compared to loud amps, and makes it easy to explore awesome combinations of effects and genuine saturated tube amp tones at low room noise levels. It's such an awesome approach, it should become the standard approach for the next couple of decades. The only complaints I had with my trial setup was too much low bass leaked from the iso cab, and too many components and cables. The basic approach is flawless.

If you crunch all these components together in a box, you have to avoid squealing.

Someone said "if this is such a good idea, why hasn't anyone done it?" Some people are not born innovators. Every time you innovate, you are by definition doing something that is a good idea, that has not been done before. There are many good ideas out there that have not been tried.

A solution for people who already have a single 2101 or any other effects processor that has an "effects loop" between the distortion and echo stages:

A fairly good solution is to put an ADA Ampulator in the effects loop. Set the Ampulator controls at 5. Add an eq and level module after the mic'd speaker. The Ampulator has a preamp tube run as a power tube, permanently driving an inductive load. There is no way provided to drive a speaker isolation cabinet instead.

A tried-and-true solution is the one I used: put a 15-watt tube amp (Laney or Fender Pro Jr. or Fender Blues Jr. are good and cheap) in the effects loop and drive a normal guitar speaker in a speaker isolation cabinet. I used a home-made box-in-a-box for double quieting, and a 25-watt Celestion Greenback. Demeter mass-produces a spk iso cab for 12" speaker. MicroRoom's tuned isolation box has an inductive load that might be permanently attached to the 6" speaker.

For a scaled down approach, you can buy a Kendrick 5-watt combo tube amp and directly drive the Micro Room spk iso cab. This approach gets down into the realm of *very* low room noise. I am not very satisfied with this approach though. The Kendrick amp isn't a rack unit. The forthcoming Kevin O'Connor tube amp *is* rack mounted, though... once this is available, before 1997, it would be more appropriate than using a traditional combo amp. I don't like using an expensive amp for this, because the amp can break from the stress. If the power amp stage were put inside the 2101, the transformer and power tube could be designed for easy replacement. Digitech would need to offer easy plug-in replacement parts and warn users that top-notch Tone requires more replacement.

The reason Fender amps have reverb and Marshalls don't: The power tubes in Fender amps are not usually saturated. The power tubes in Marshall amps are usually saturated. Echo, reverb, and other time-based effects cause muddiness when placed before distortion. Saturating power tubes in an amp's power-amp stage are like a distortion box. If you use reverb in a saturating tube amp, you are doing the following sequence:

o Preamp distortion
o Reverb
o Power amp saturation
This is like:
o distortion
o echo
o distortion

Everyone knows that echo-->distortion sounds bad, but that distortion-->echo is ok. But fewer people understand that reverb-->power tube saturation is the same as as echo-->distortion, and just as bad.

You can put moderate echo before moderate power tube saturation, with only moderate muddiness. But really pure and mind-bending tones are available by putting intense power tube saturation before intense echo.


I'm just a typical guitarist who wants to combine effects with cranked tube amp tone, at acoustic-guitar volume levels. After years of experiments and thinking, now I am a *packaging guru* for guitar processing gear, emphasizing the ideal combination of effects and low-wattage power tube saturation. The realm of the amp guru is too circumscribed: they are all trying to reinvent the same approach, and they end up with the same drawbacks -- room noise level is tied to the Tone. The overall volume level is not programmable independently of the Tone. The effects gurus have no innovative thinking about tube amps and speakers -- the effects industry and the amp industry plod along, stuck in their old divisions. For a radical increase in control of levels and processing sequence, you've got to put the cranked tube amp inside the effects, rather than putting the effects before the amp.

The effects people say "we'll let the amp gurus take care of Basic Tone, we'll just handle the effects that happen before the amp." Big mistake. As soon as you put echo-type effects before the amp, you've muddied the tone. There is no way to have intense echo before intense power tube saturation, without causing a mudslide of beats and harsh, gummed-up saturation. Try putting an echo pedal before a distortion pedal. It sounds terrible. You have to consider a tube amp as a distortion box that happens to produce a lot of room noise. A distortion box has an output level control and can be placed before echo. By putting a cranked tube amp in the effects loop of an effects processor, you gain the same control over final level and placement sequence. The only *final* level control a traditional tube amp has is the volume slider on the mixing board in the control room of a recording studio. It's terrible the way tube amp tone is absolutely locked onto the overall sound level produced by the amp. The knob marked "volume" on a tube amp should be labeled "volume & Tone". Imagine a distortion box that combined the gain and level controls into a single knob -- that's how unwieldy tube amps are. But a speaker isolation cabinet enables you to confine the "Loud Space" and have a level control on that whole signal that does *not* alter the Basic Tone. Just like the isolation room of a recording studio, and the volume slider in the control room.

So many people repeat that the best "amp" gear has already been invented. But they have no ability to think outside the lines of what has been. The very concept of "guitar tube amp" has become the worst hindrance to innovation. Instantly, assumptions are made: that it's *loud*, that tone shaping and audible amplification should be combined.

You have to separate amplification for tone shaping from amplification for monitoring. The first amplifier is for shaping tone, the second one is for monitoring. There are advantages to *not* being able to hear the tone-shaping amplifier. By isolating the tone-shaping amplification and putting it out of hearing range, you have far more control over the final sound that you do hear - once you've added level control, eq, and delay-derived effects to the tone-shaped signal from the first amp.

There are many inductive loads and speaker simulators listed in the 96-97 Guitar & Bass Buyer's Guide by Guitar Player. If I average out the opinions I've heard (they fit well with my experience), I'd say that 2/3 of cranked amp tone requires power tubes and 1/3 requires genuine speakers. If you use a load instead of speakers, you can get 2/3 authentic cranked-amp tone.

According to most people who have tried inductive loads, speakers are an essential factor of traditional cranked-amp tone. Theoretically, you could synthesize the transfer function of a mic'd tube amp. Until that is achieved, all the evidence from people who have used inductive loads certainly indicates that hard-driven speakers are essential to the basic tube amp tone. Power tubes and speaker isolation cabinets are a stop-gap measure to get genuine cranked-amp tones at low room noise levels. Maybe a computer chip can create the same transfer function. Maybe an inductive load could be perfected. Maybe careful equalization and dynamics processing can perfectly emulate a cranked tube amp. There are several hypothetical solutions to eliminating the literal power tubes and speakers which are necessary to shape the Basic Tone. But for the moment, there is a clear cut solution: don't skip the power tube, and don't skip the hard-driven guitar speaker. Use a low-wattage power tube, such as a single 6V6 in Class A configuration, to directly drive a low-wattage speaker in a soundproofed speaker isolation cabinet. Rather than imitating a cranked tube amp, design a scaled-down cranked tube amp. This configuration fits especially well in the middle of a programmable multieffects processor, which would have to be designed properly around the scaled-down tube amp. This is technologically trivial, simply involving new configurations of existing gear.

Well-designed power tube equipment should acknowledge that for every element of an actual big tube amp that you leave out, there is an increase in convenience but a decrease in the quality of the Basic Tone. The 2101 does not have power tubes, speakers, cabinet, inductive load, or microphone. It only has a speaker simulator -- just a low-pass filter, essentially. And the Basic Tone which the 2101 is able to produce is accordingly unfinished. The 2101 depends on a cranked amp placed after it to get a top-notch tone... but even then, the cranked amp gets confused by all the detuning from delay, and as a whole rig, you have no control over the overall level... if you turn down the tube amp, that will alter your Basic Tone. With this standard "programmable effects before tube amp" arrangement, the overall level is unfortunately tied to the Basic Tone.

Kevin O'Connor is about to make available a rack-mount 1-to-10 watt tube power amp. He wrote the book _The Ultimate Tone_. I don't know if he is complicating it by adding tone controls and a distortion preamp. This amp will be perfect for driving a speaker isolation cabinet. Still, it would be much better if Digitech put *just* the power amp stage inside a processor. If you buy the O'Connor amp, you would leave all controls at 5, and not really use the entire preamp section.

Warning about using the ADA Ampulator instead of the discontinued H&K Blues Master -- it can't directly drive a real speaker. The Blues Master enables you to directly drive a speaker cabinet, without using the inductive load. The 12AX7 tube in the Ampulator is running as a power tube, and this tube is permanently connected to the inductive load (through an output transformer, I presume). According to the owner of one of these units, there is no jack to connect the output tube directly to a guitar speaker. So the Blues Master supports convenient switching between using a speaker (such as a speaker isolation cabinet) and faking the speaker with an inductive load.

Ampulator: http://www.adasignal.com/pages/ampu.html - time machine required. I so wish I archived all this material. That would be cool to keep the site alive.
Blues Master/Crunch Master: http://www.tonygoodall.clara.net/music/mus_hk.htm
Kevin O'Connor's rackmount 10 watt tube power amp will be announced on his web site, which might be http://www.wwdc.com/~power/index.html

I discourage people from using discontinued gear such as the Blues Master, because the guitar processing gear industry needs to move forward and mass-produce better new configurations of gear. Used gear is not a solution to my chosen problem, which is: how everyone can combine existing gear in innovative ways to get genuine cranked tube amp tone sequenced ideally with effects, without blasting.

Amptone.com ultra gear-search page

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