Starved plate tube design-can it sound like a "real" tube design?

[chessparov]

Rather than naming (manufacturers) names, just wondering how close a
well executed starved plate tube design can mimic a "real" tube design's
sound?

Thanks
Chris

[Knox]

Originally posted by chessparov
Rather than naming (manufacturers) names, just wondering how close a
well executed starved plate tube design can mimic a "real" tube design's
sound?
Chris

Chris . . explain what YOU mean by STARVED?
BTW . . . . I am a HUGE plate believer.

[chessparov]

Sorry if my question wasn't clear.
Meant in the context mainly of the manifold "toob" mic pre's that normally
sell for much less than their "true" tube counterparts ala Manley.
My understanding is that a "plate design" has less voltage going though it.
They seem to carry a stigma that made me wonder if it was feasible to
make one to rival the real thing, or if the inherent design doomed it to
eventual Banjo Depot hell.

Chris

[Knox]

Originally posted by chessparov
Sorry if my question wasn't clear.
Meant in the context mainly of the manifold "toob" mic pre's that normally
sell for much less than their "true" tube counterparts ala Manley.
My understanding is that a "plate design" has less voltage going though it.
They seem to carry a stigma that made me wonder if it was feasible to
make one to rival the real thing, or if the inherent design doomed it to
eventual Banjo Depot hell.

Chris

OK . . you are talking the well known Viking language to a guy that talks 44th street.

I was under the impression you were asking about a plate reverb and the differences between tube pre amp versus transister. . . . *smile*. . . . THAT kind of shit I could help you with!

Geez . . . If I got more technically dumb, I would be a ham sandwich.

I twist frikkin' knobs until shit sounds good. Anytime you hear me acting like I understand some electronic type shit here . . . have me choked. If I solder a cable . . . the whole building has to be re-painted from the damage.

[chessparov]

And God forbid my Christmas tree lights go out!
(just ask my wife)

This thread then is our "Toob 101".
Is there a professor in the house?

Chris

[Gone Fission]

A non-expert explanation:

In traditional designs most of the time the voltage on the plates (annodes?) of a 12ax7a is at least 150 volts, and often 300 volts or higher. Generally speaking, higher voltages, within the tube's operating range, mean higher dynamic range. Most of the cheap stuff marketed at the project studio market tends to just have a tube or two in one stage of a design that is mostly cheaply opamp circuitry, and typically run at around 50 plate volts, aka a "starved plate". This stage, mixed in to crap up a crap design in an allegedly cool way, offers no dynamics, no headroom, no bandwidth. Because these boxes are generally marketed at musicians, who associate tubes with distortion ala guitar amps, they don't understand that tubes can as clean and pristine as transistors or opamps, and even sound great like that, so they think this is what high end tube gear is supposed to be and are happy with shit gear.

I suppose it is possible that there can be positive applications of a starved plate, but I haven't met it. The Studio Projects preamps blend function might have potential, though, since it's in parallel to the normal circuit, preserving bandwidth and dynamic range while blending in a smoother, thicker character. While some like the feature, I think some have been unimpressed, so who knows?

Bear

[Knox]

Originally posted by Gone Fission
A non-expert explanation:

In traditional designs most of the time the voltage on the plates (annodes?) of a 12ax7a is at least 150 volts, and often 300 volts or higher. Generally speaking, higher voltages, within the tube's operating range, mean higher dynamic range. Most of the cheap stuff marketed at the project studio market tends to just have a tube or two in one stage of a design that is mostly cheaply opamp circuitry, and typically run at around 50 plate volts, aka a "starved plate". This stage, mixed in to crap up a crap design in an allegedly cool way, offers no dynamics, no headroom, no bandwidth. Because these boxes are generally marketed at musicians, who associate tubes with distortion ala guitar amps, they don't understand that tubes can as clean and pristine as transistors or opamps, and even sound great like that, so they think this is what high end tube gear is supposed to be and are happy with shit gear.

SEE. . . . This is EXACTLY what I told him! He wouldn't listen to me!

[Midlandmorgan]

I think you can get pretty close, but the input has to be really hot to get any 'tube' characteristics (I.E., distortion AKA warmth)...increasing voltage to the tube, so I've read, will also raise noise levels and shorten tube life...

So the answer is ... I have no idea .... But running these starved plate designs fairly hot at the iput can make a big difference....I've got a cheapo ART TubePAC that I use for certain guitar micing needs....I put a JAN 5851 preamp tube in... this is a lower gain version of the 12AX7, which lets me run the preamp hotter... also, bypassing the internal "compressor" seems to help a bit in letting the tube do its mojo...

[atticus]

Starved plate tube designs are 99.99999% marketing crap. They use $1 Chinese 12AX7's basically as high pass filters in a horribly misguided attempt at "warmth", and honestly it jacks up the price while at the same time screwing with the sound. There are some hybrid tube/solid state designs that are quite good. Manley's 16x2 mixer comes to mind in this scenario, a design that uses both tube and solid state at various places in the signal path to combine the two colors. But your basic "toob" stuff is not good. You want "warmth'' in a pre? Get some well designed iron in the signal path.

[Drumsound]

Originally posted by Knox


I twist frikkin' knobs until shit sounds good. Anytime you hear me acting like I understand some electronic type shit here . . . have me choked. If I solder a cable . . . the whole building has to be re-painted from the damage.

I'm so with you brother Knox!

[Coldsnow]

Just my non-scientific listening perspective. I don't necessarily like tube for warmth as said before transformers are better at that than tubes in my opinion. Tubes are for a more roundness of the sound. What I like abour high voltage tube gear is the movement or dimension (life) it adds to the sound that lower voltage equipment doesn't give. I would classify ARt preamps for instance as warm and colored but there is no dimension to the sound. This explanation may not make any sense to anyone other else it's just what I hear.

[cram]

I've checked out both hybrid designs extensively, the "Starved Plate" design, and the hybrid "Tube on the Output" design. Neither obviously, sound like a real Class A tube pre. "The Starved" plate design is basically a distortion box that I have found unuseable on most sources. However, I do like it on bass guitar.

The "Tube on the Output" design is much more sonorous and flexible, again IMHO. Even though in this design you have the tube running at 200v plus, it is still there as an effect. I think the trick is to understand that these are "FX pre-amps" and should be treated as such.

Oddly enough I have found that differing tube type dramatically alters the sound in "Starved Plate" designs. You would think that since the tube is operating at near failure voltages it really wouldn't matter much. But it does. I'm sure an EE could tell me why. Differing tube type alters the sound in the "Tube on the Output" design as well, but to a lesser degree.

I've tried both the ART Tube MP and dbx Mini Pre with the new GT 12ax7c's and they definitely sound better. The new GT12ax7c is rated down to 40v, so it is within spec of these units.