Not true. The original intent for the Pultec was as a program EQ.Of course, those things aren't designed to be clean. They are considered to be colored units.
Not true. The original intent for the Pultec was as a program EQ.
That was a long time ago. By today's standards they are valued for their color, not for being clean. I suppose the same could be said of a Fairchild tube compressor. They were originally designed to be clean-as-they-knew-how at the time. Same for an LA-2 compressor. Neve line amps. The list goes on and on. If you want to compare to a good sounding much more clean type EQ that was designed quite awhile ago, try a Massenberg.
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But you used the word "designed". They were designed to be a clean sounding unit in the context of the time.That was a long time ago. By today's standards they are valued for their color, not for being clean.
But you used the word "designed". They were designed to be a clean sounding unit in the context of the time.
Okay, sorry for any confusion on that issue. Let me try it this way: The were designed to sound as they do, which is to say, clean by standards of long ago, and colored by today's standards.
BTW, for those unfamiliar with a VT-5, it is a stereo VT-4 tube EQ similar in function to an old Pultec. The VT-4's are rated as: THD + Noise <0.10% 20 cps to 20 kc.
Here is a quote from one owner at GearSlutz: "I've got a pair of the Vt4s. They are very musical eqs. A "make anything sound better" type EQ. Pultec-esque but with their own thing going on...maybe 'a bit more modern and hifi'."
Okay, so the point of the quote is to illustrate that at least some people buy them for their very nice coloration. No surprise there.
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I have one of a kind EQ outfitted with Teflon caps, every time the EQ settings are changed I have to wait 100 hours for the new setting to break in.
I have one of a kind EQ outfitted with Teflon caps, every time the EQ settings are changed I have to wait 100 hours for the new setting to break in.
Terrible isn't it after a 100hr and the THD goes from -135 dB to -132dB.
Not to forget mentioning the silver on Teflon PCB's in my gears, after a session of grand piano gone through the system I have to put my gangster-rap collection on rest for another week...
Have you listened to one? Or even a Pultec for that matter?Okay, so the point of the quote is to illustrate that at least some people buy them for their very nice coloration. No surprise there.
And when I say "listen" I mean actually audition one where you turn the knobs and hear the effect.
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Nope, similar but not those. But, rated at <.1% distortion, and made with tubes and iron, I get the idea. And, I expect the user evaluation is probably about right. He said it makes everything sound "better," and I didn't quote, but he also said it's good for removing the "digital" from sound. If it were actually low distortion, it couldn't filter out "digital" which by it's nature would not and could not be a linear process. Same for making everything sound "better," not a linear process, so it has to involve some type of distortion. Although, the distortion may be very pleasant.
Also, when I have heard other highly rated pro tube gear, it's not usually to my taste. At best it sounds different than the best digital I have heard, maybe better in some ways and worse in others. Usually, I choose to skip it, but other people may really like it. However, it can still be good for some things. I like a little distortion at times too, but as it turns out most of the best sounding classic gear with subtle distortion that sounds "good" is solid state.
Also, when I have heard other highly rated pro tube gear, it's not usually to my taste. At best it sounds different than the best digital I have heard, maybe better in some ways and worse in others. Usually, I choose to skip it, but other people may really like it. However, it can still be good for some things. I like a little distortion at times too, but as it turns out most of the best sounding classic gear with subtle distortion that sounds "good" is solid state.
I can tell you haven't played around with a lot of analog EQ's in the context of doing recording.
What is that supposed to mean? That I like digital EQs? Or that I don't like clean analog EQs? I will take a good, clean analog EQ any day over a digital one. I will take the right mic choice and placement, and the right preamp, over using any EQ if I can get the right sound that way. What EQs do is not usually what I want, especially EQs with stepped frequency and Q. It's rough at best trying to get it just right.
I have a Massenberg, but I have never used it. I just don't use EQ for quality reproduction.
EQ is back in fashion due mainly it seems to DSP, are people really less likely to screw up the sound though than they used to do with analogue?
You couldn't read between the lines when the guy was talking reducing the digital quality of a sound. You just assumed that the tube distortion was automatically masking the digital quality of the sound. It's more complex than that, especially in a LC filter based unit.What is that supposed to mean?
Good unit for radical surgery. Not a very musical unit.I have a Massenberg, but I have never used it. I just don't use EQ for quality reproduction.
You couldn't read between the lines when the guy was talking reducing the digital quality of a sound. You just assumed that the tube distortion was automatically masking the digital quality of the sound. It's more complex than that, especially in a LC filter based unit.
I believe I referred to "tubes and iron" at one point. They both distort some. My understanding has always been that both types of distortion are involved.
But, look, in the big picture it doesn't matter if the distortion comes from tubes and/or iron core devices, or something else altogether. It only matters that some kind or other of distortion is masking and/or distorting digital sound quality. It can only happen through nonlinear distortion. So, to the extent the box is good for making "everything sound better" and obscuring "digital" sound quality, the unit is a nice sounding distortion effect that also does EQ. Some people may think it is absolutely gorgeous sounding, which is only to say they really like the distortion it produces. Nothing wrong with that if one happens to like it.
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Totally missing the point about why the EQ sounds good. It's the filters that sets Fern's EQ apart from the rest. Doesn't so very much, really matter if they are couched in tubes with/without iron or SS.... as long as the amplification is reasonably resolving.
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Well, hopefully I can get back to serious audio design.
I find that many here simply do not experience audio quality design like I have for the last 50 years.
Nothing is ever perfectly designed well enough to be called 'truly transparent'. It is just that we don't seem to have the answers for what our ears hear, although we can now make designs that measure very well. It isn't frequency response differences, for example, that always makes one amp sound 'brighter' than another, yet many persist in this belief. AND, one can make a preamp design with op amps that measures almost perfectly, yet another vacuum tube or discrete solid state design might sound better enough to establish a reputation for quality sound throughout the world. WHY? (And don't tell me I am imagining things, I know better!)
Good question, John. For my part, I've been closely associated with a designer here in Australia since the mid-1970s. His designs were, arguably, way ahead of pretty much anything available anywhere. Many of his ideas have been taken up by other designers over the years (not saying they copied him, BTW, just developed similar ideas). How's this for a 1977 design?
* Zero global NFB.
* Collectors to load.
* Over-sized power transformers. (2.5kVA split wound transformer for a 180 Watt @ 8 Ohm)
* A large number of small filter caps (the largest design employed 92 X 3,300uF caps)
* All transistors are matched to within 1% for hFE and Vbe. Also, pre-drivers and matched to drivers and driver to outputs.
* Output devices were high speed (20MHz + ) Not bad for 1977.
* No output inductors.
* No output relays.
* No coupling capacitors.
* No current limiting in the very early designs. When the amps were first used with the Infinity RS4.5 speakers, that design flaw was changed. The RS4.5 possessed a measured dip to a little below 1 Ohm. It caused problems, so the first power amp was revised with a current limit point of 100 Amps.
* True, dual mono design.
* DC ~ 150kHz
* <0.1% THD and IMD.
* Output impedance < 0.04 Ohms (DC ~ 20kHz)
* Unconditionally stable, regardless of load.
These amps have stood the test of time and even the very earliest models can equal most amps available today. I am convinced that the lack of global NFB is a major factor in the immediacy and reality of the sound.
And, most critically, the designer of this stuff has a shrine set up in his workshop, with a photo of you at it's centre.
Nah, just kidding, but he regards you very, VERY highly indeed. You two would probably get on quite well.
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Your amp designer is my kind of designer. Does he make any commercial products?
His business was very successful (in Australia) from 1976 through to 2003, when a divorce forced him to close the business. Although there is considerable demand, it seems unlikely he will re-start in any significant way. Still, we hold hopes for that. In the intervening time, he still offers support for every product he has ever manufactured (I do much of the work for the Sydney area), so demand for older stuff remains healthy.
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