A new type of tube guitar amplifier

[GONZO-X]

i just found out about this thing....

i'd be curious to know if anybody else knows anything about it.....


A NEW TYPE OF TUBE GUITAR AMPLIFIER

(my apologies if this has been covered before)

GAGA-50-- Advantages: All-tube, 5 pounds, 50 watts


lighter and smaller than typical tube amps & lighter than comparably powered transistorized amps

no audio output transformer or its limitations and distortions

freedom to use any number or combination of octal output tubes

widely adjustable output tube distortion vs output volume level

immediate recovery from overdrive; touch-responsive output tube distortion

drives any load and sustains dead shorts or total disconnects at full power

automatic bias and automatic idle / standby of any number or combination of output tubes

lower operating temperature, greatly extended tube lifetimes (expected)

increased reliability and stability, improved amplitude and phase accuracy

more perfect coupling of output tubes to speaker (i.e., no parasitics or saturation)

more tube-like operation of output tubes (i.e., lower current, higher impedance)

triode-like characteristics presented to speakers, even from pentodes

advanced, fully regulated, switching power supplies

no heavy power transformers, magnetics or choke filters

world power ready: plug and play anywhere

powerful, agile, innovative: brings true tone closer

full power over unmatched, wide frequency response

top-quality parts, USA made, high-end audio pedigree, experienced designers






http://www.milbert.com/guitar

http://www.thegearpage.net/board/sho...1&postcount=42

[DrewPeterson7]

Hmm. A lot of talk about how awesome its specs are, and not much about how it sounds.

About halfway down their page I found some clips. Listening now through Skullcandy earbuds, I'm not blown away. The stereo micing ("Right channel: Shure SM57 dynamic microphone placed 12 inches off-axis below and in front of Marshall 4x12 with Vintage 30 speakers, in anechoic / dampened room. Left channel: AKG C-3000 studio condenser microphone set 2 meters away in same room.") just makes the whole thing sound odd, and the focus is mostly on cleaner tones.

GAGA-50 offers all-tube "wideband" amplification to unmatched extreme as it more perfectly matches output power tubes to speaker loads. Low frequency response is flat down to near DC and flat up to well above 20kHz

This worries me, TBH. This guy is a high fidelity stereo amplifier developer, and is trying to leverage that into amplifier design. Yet, for the past 60 years of electric guitar, part of the sound of rock guitar HAS been the very innefficiencies in an amplifier circuit. A Marshall plexi is nowhere near full frequency - that's half the point.

[GONZO-X]

yep, i have no way to know from the clips, whether i'd really like it or not.

now, if the technology gives me the ultra deep lows i like, without the mud or midrange, and the high end can easily be sweetened....

if the distortion levels are much more variable than the clips show...

if it takes pedals well.....

i can see how this COULD blow away all other tube designs.
everything i HATE HATE HATE about tube amps, this amp does away with. (i'm a tube amp snob i guess, i've played tube amps of every make and model since 1975)


but, the proof is in the pudding, as they say.
i gotta not only hear one, but feel the way it translates what i do, thru the speaker.

that is golden.

[Zaphod B]

Hmmm. Interesting, a wideband guitar amp.

I think the clean samples sound OK but not particularly full. The overdriven samples are pretty gutless considering they're using a 4X12 cab.

Still, though, it's not a bad sound and will probably develop a cult following.

[Zaphod B]

I'll add that there are probably countless examples of recording sessions where guitarists plugged directly into a board to obtain whatever sound that would produce, so there's nothing unique about the wideband aspect of it.

I've run a guitar direct into a PA board (no guitar amp at all) just for shits and gigges, and it sounded pretty cool. But different.

[Zaphod B]

And further......

There is absolutely no reason that the holy grail of amplified guitar sound should be based on transformer-coupled vaccuum tube designs. It's what we're used to, and what has been shown to work. So far.

That's what puzzles me about modelers and Guitar Rig setups.....if you can model any kind of amplified sound, why not break some ground?

[DrewPeterson7]

And further......

There is absolutely no reason that the holy grail of amplified guitar sound should be based on transformer-coupled vaccuum tube designs. It's what we're used to, and what has been shown to work. So far.

That's what puzzles me about modelers and Guitar Rig setups.....if you can model any kind of amplified sound, why not break some ground?

...except, because that's what every single rock guitar record we grew up on and were influenced by and were made to fall in love with the guitar through was recorded by a guitar amplified in this manner, so it's part of the "sound" of rock guitar. Ever played a guitar plugged straight into a keyboard amp?

The other weird thing about this is they're spending all this time bragging about how full-frequency their amp is and how that's sort of important, and then running it through a 4x12 guitar cab. Any fidelity gains would immediately be lost there.

I'll be interested to hear and play one of these, but my gut reaction is this is an amp based on a premise that I find kind of questionable, and marketed based on a very long (and admittedly impressive) spec list, but not based on what it can actually do.

Oh, and spot on about modelers - the day I get interested in modeling is the day they start trying to do things you can't do with conventional vacuum tubes.

[GONZO-X]

the technology is definitely cutting edge.



Technology

White Papers

ZOTL Technology vs Audio Output Transformers

This paper demonstrates the electrical performance of an amplifier using the ZOTL technology versus the identical amplifier using a high-quality audio output transformer and presents these differences using oscillographs.

Electronic Devices and the Amplification Process

This paper shows how a curve tracer can be used to explore the attributes of the ZOTL technology and contrast it to the shortcomings of the audio output transformer. Also shown is how this tool can be used to optimally design an amplifier.

Patents

5,612,646 Output Transformerless Amplifier Impedance Matching Apparatus

This patent teaches the principles behind the Berning ZOTL technology that can properly match the impedance of vacuum tubes to the impedance of speakers without using audio output transformers. The impedance conversion is done with dc-dc switching converters operating at fixed frequencies well above audio frequencies. The actual voltage and current impedance transformations are done via special high-frequency transformers. This is an RF carrier system that eliminates the frequency-dependent distortions present in audio transformers, and can enable the amplifier to have a wider frequency response and be dc coupled.

4,163,198 Audio Amplifier

This patent details a hybrid tube-FET amplification stage that forms the basis of the Berning TF-10 preamplifier. An important advantage of this amplification stage is the elimination of the parasitic feedback capacitance and thus providing a stage with improved transient response.

3,995,226 Audio Amplifier

This patent describes the screen drive philosophy that has become an important part of many of the Berning power amplifier designs to the present day. The screen drive allows tubes to be operated at much higher efficiencies, much higher power output, and at greatly enhanced reliability. Whereas the patent shows transistors driving tubes, the same principles apply to presently implemented versions of tubes driving tubes. This is also known as the "enhancement" amplifier.

[GONZO-X]

and if none of that makes any sense, check this out:


DAVID BERNING’S ZOTL

http://www.positive-feedback.com/pfb...ucted.7n5.html

(3RD TOPIC DOWN)

[ermghoti]

the technology is definitely cutting edge.

So are Line6, noiseless single coils, Gibson's Robot Guitar, graphite necks, and a lot of other things guitar players hate. It seems like a fantastic hifi amp, with the output tube distortion feature added on. I have no idea if that will translate to good tone.