What is conceivable is fine. A commission on voicing is fine. The idea that a luthier only produced for one type of music/venue in that era is nonsense. And it’s going to take an actual historical quote to say otherwise.

That's in effect what I'm saying: that 'market supremacy' can take various forms....a drive for strict uniformity of performance, and a limited product line (think Coles 4038 ribbon, unchanged for decades).

Or Schoeps diverse product line of mics, which maintains performance uniformity (so that stereo pair matching is essentially irrelevant), but their mics are designed and manufactured ('voiced') for specific uses and venues.

A manufacturer could take either or even both approaches, depending on how ambitious and how much market share they intend to claim

Yes, Doug Fearn is a good friend of mine as well as Bill Whitlock who was the CEO of Jensen Transformers when he first started helping me. Both of those guys have been there for me all along the development of my preamp/limiter design concept. Everyone has their own vision of what a preamp should sound and look like. I had my vision that was a result of my own studio requirements. I must have a thousand emails with those guys. I owe a lot to them... and others.

I have been designing electronics since I was 10 years old in 1962. Back then everything was vacuum tubes (hollow state). I later designed in solid state and was published with IEEE when at Stanford.

Can you define the word Transparent for us?
Then tell us where you would use a Transparent preamp vs one that is not.

Jim Moss

Is that what you need? Go look for it. Visit the library. There is lots of history there. The people who collect these instruments have lots of history on them.

I don't understand how you could be shocked at this. Do you think that all violins where made to sound the same? Have you had any association with violins? Back then, violin makers would get orders for violins. They wanted them to be built for specific uses.

Heifetz owned one of each for different uses.

So, lets look at a more modern case. Have you ever heard of the F5 mandolin? Have you ever heard of Lloyd Loar?

My point in my post is that different kinds of performances sound different as do the venues they performed in. This can have an impact on the way one might want to record them. A violin solo in a hall can be one sound. While a solo violin in a chamber environment might want another method of recording. This guy who asked the question seems to be a violin player. His recorded sound on an album is up to him and can take a number of forms.

Jim Moss

I concur. I have make many recordings of acoustic music (mostly folk, but also some classical; some even used tube microphones) where Mastering Lab and Demeter VTMP mic pres played a prominent role. I consider these examples of "clean" preamps and not "saturation machines".

Absurd commentary.

exactly! - the 1st violinist in one of the two large orchestras here is given a stradivarius by a foundation: she plays it depending on the hall, repertoire, instrumentation - or not!
her second instrument is a much newer instrument: i couldn't say that it sounds much worse or, depending on the situation, is even the better instrument. however, it demands a lot from the violinist in terms of adaptation, which she masters with aplomb.

A transparent device sounds the same going in as it sounds coming out. Put a 40dB pad in front of your 40dB mike preamp and listen to the input and the output and they should be identical. Or as close to identical as you can get.

Now, as far as when I would use a transparent preamp vs. one that is not, that's a personal issue and I am personally very much in favor of preamps that are flat, have low coloration, and don't have any inherent limiting. So I would almost always use a transparent preamp, but not everyone feels the same way I do. (Which is why I sell a very colored preamp for instance.)
--scott

That seems reasonable Scott. However, just listening is not really enough to test for no change from input to output. Here we use various audio analyzers and test circuits. Run them over the spectrum from 0.5 Hz to 55 kHz and see how flat that is. Then check for THD over that range and again over 10 to 20kHz. Ears have lots of processing from the ear to the brain. An example is Masking.

Personally, and you did mention this is a personal issue, and situational I might add, I don't limit myself with rules like "Transparent only". I see the recording engineer/producer/musician as oil painters... Not photographers. All your available technology including the room and your smarts are colors on your painters palette to be used or mixed to get the effect you want in your recording mix. I don't think I am a renegade here either. Depending on the project, I can use lots of things that color the sound, like large diaphragm vintage Neumann and AKG mics... or ribbon mics. Add to that mic and room techniques. What I produce is not a photograph, but an audio painting soundscape. Very few people I have talked to, and I have toured around the world, listen to a recording to how realistic it sounds. However, there are the direct to disk fans who really like it if the chair squeaks or if someone's stomach is picked up growling.

That is why in my vacuum tube mic preamp/limiter design I wanted there to be options. There are the options for high or low gain, negative feedback or no negative feedback, and optical limiter or no optical limiter.
http://www.mosswareproaudio.com/
If you look at the front panel of my preamp you will see two knobs, like a compressor, that can be used to produce anything from a sparkling clear transparent sound all the way to a warm hard driven 2nd harmonic colored sound and everything in between. It is up to the artist/engineer/producer. On this preamp design I can get 0.02% to 0.05% THD+Noise (20Hz to 20kHz). That should produce what you are calling a transparent sound. I can mix a sound that has power in a small room or a concert hall. That is the Art in recording and mixing. It all depends on your artistic vision.

Jim Moss

I used an ADL 600 pre for years but have found decent quality tube mics do a much better job of delivering the much needed tube/transformer sonic signature than any tube pre amp.
Hugh

Good. If you get what you are looking for that is great. You could also try out a more expensive vacuum tube mic preamp and see what that can produce for you. I found there to be a big difference between the $1,000 range and the $4,000 to $5,000 range preamps. Thing is, if you are happy with the gear you are using that is all that counts... until you are not. I could never produce my preamp for $1200. There is much more than that in parts, let alone the machined front panel and enclosure components.

I mean, in transformers for example, you get down to the makeup of the core for the sound quality (I don't mean good vs bad). There are steel-core, nickel, nickel alloys, etc. They all sound different in ways you would notice if A:B'ed in your studio. Then there is the testing that goes into the transformers. I was surprised to find that some international companies don't even characterize their audio transformers. If you talk about it to them, they just look puzzled. That is just audio transformers. There is circuit layout, active components, power supply designs. A lot goes into a fine preamp product, which is the cause for the higher prices. And the POTS... my gosh... There is a world of it's own. I took three months dissecting and inspecting potentiometer designs. There is the function of course. Then construction. Then there is the feel. You want a positive feel on all switches and pots in a great preamp that will last for at least 40 years. It has to feel GREAT. What is called sexiness in marketing circles. You know it when you feel it. I took my artist girlfriend through the San Francisco AES show one year, just feeling all the pots and switches. She said to me, there is clearly a difference between a VW and a Rolls Royce products here. Then getting pots. You can get anything you want if you are ordering 10,000 of them. I know a console company that went out of business in part to the inability to get a potentiometer they needed. It just goes on component by components. Also, great looking gear will help sell studio time for years to come.

Personally, my experience with a Neumann U67 broke me of tube mics. They are just too clean. There is no color character. So, I traded it to a fellow recording engineer in 2000, for a vintage Neumann U87 and a UREI 1176LN. The textured sound that I get from a Neumann U87, U47-fet, KM184, AKG 414B ULS can add to the texture or gain of the recorded instrument within the mix. I am not a big an of ribbon mics either. I might be if I recorded a lot of saxophones. I have a RCA 77-DX, but it is not my first go to mic for strings. I have the Mad Dogs and Englishmen film and there they use RCA 77-DX mics on the horns a lot. Sounds great. I recently recorded a dobro on AKG 414B ULS and a RCA 77-DX. They were really different. They both had their own sounds. They sounded great too. It all depends on what is around that track.

Jim Moss

Measurements don't tell you if it's transparent or not. Measurements tell you why it's not transparent when it isn't. Measurements are absolutely essential in order to quantify coloration but there's no objective scalar that will indicate the level of coloration in spite of the best efforts of Geddes and Lee.

And yes.... a system can have massive amounts of distortion and still be transparent, if that distortion is inaudible. That's the whole point of perceptual encoding! Current perceptual encoding systems are still far from transparent but they all sound far better than traditional measurements would have you think.
--scott

Well... Explain how that can be.
If I measure 100 points by inserting a single frequency tone and measure the output, after removing that tone, at that point and others along the bandpass it will tell you that there is no other tones other than the one you inserted. If that measurement, made all across the band is flat, where does the color come from?

To use your ears, with all the variable compression your hearing has, as well as frequency response issues, it is not a valid measurement of anything scientific. How can you tell that what you hear has any relationship at all to what someone else will hear. You can't be in someone else's head and hear what they hear. And what about the room effects on what you hear. And I dare you to bring up heterodyning.

Remember, you defined transparent as
"A transparent device sounds the same going in as it sounds coming out."
To use your ears to measure this is not scientific.

What you are describing is a perception measurement, different for each listener. There are a ton of peer reviewed journal articles on hearing impairment that cover all this to the N'th degree. They are describing variations from normal hearing. They cover things like psycho-acoustics there. You might want to check them out. I learned a lot doing that, back in college (the 2nd tour) in the 1990s.

If it's not scientific, then it is snake oil.
However, if that is good enough for you, then that is great.
Recording is about art.
Whatever makes you happy.


Jim Moss

JMOss1 wrote: "Personally, my experience with a Neumann u67 broke me of tube mics. They are just too clean. There is no color character. "

Could you please explain this a bit more. How do you define "color".
I have to say that this is the first time I have heard someone claim that the U67 has no color character.

You made your point well with this distinction, but in reality there isn't a sharp dichotomy between oil painters and photographers. It's more of a continuum.

The exact same debates about "transparency," "realism," and "character" occur in photography too. Some photographers seek lenses that are optically perfect; others seek lenses with spherical aberrations and other "defects" that add character, making their photographs perhaps less realistic but more beautiful or mysterious. And there are art photographers who spend as much time working on a single photo as a painter does on a painting.

A photographer I studied with likes to emphasize that photographs are not reality; they are representations of reality. And he likened the character in his lenses to distortion on a guitar, degrading image quality for the sake of beauty. Just as many musicians like to play an instrument that asserts its own intrinsic character, when a photographer shoots with character lenses the lens becomes a partner in the artistic process rather than merely a tool.

You can't even neatly split it out by genre: some documentary photographers like to use character lenses, and some portrait photographers prefer to use clinical, optically perfect lenses and apply effects to taste in post.

I agree. I have a collection of vintage Japanese and Russian lenses here too. Some are radioactive.

What I should have said was, Snap Shot photos. They try to produce photos that document a vacation or project. I too am involved in artistic photography. When I was referring to paintings I was thinking of the renaissance.

In fact I took the photos on these websites.
Asahi Super-Multi-Coated Takumar 28mm f 1.35
http://www.mosswareproaudio.com/IMG_0272sST2cL.jpg

Fujinon 55mm f 1.8
http://audiogearfortheartist.com/IMG_0046sF2-L.jpg


Jim Moss

it's pretty far from clean by most people's standards but compared to other mics, i can understand that someone calls the results as being 'clean'...

...but then it also depends on the particular mic, the mic/preamp/converter combination and of course the room and the situation/application/processing.

I don't define color. If it is there you can hear it. It is up to me to select the coloring that I think fits the recording. Color in this case depends on the mic. In the case of the U87 the color is in the form of timber and texture, like in film grain.

It is hard to put sound to words, but let me try something here. Look at this photo of the front panel of my preamp design.
http://www.mosswareproaudio.com/IMG_0272sST2cL.jpg
I used a Asahi Super-Multi-Coated Takumar 28mm f 1.35 lens with Canon 2000D.
The lens is taking advantage of the short depth of field to produce the out of focus background.
The Canon is in portrait mode with a little distortion selected. Something like a 1/4 Black Promist filter.
These are similar to what I get from a Neumann U87 or AKG 414B ULG mic.
There is this soft grain thing going on that adds some magic to the sound and the photo.
It adds a becomes bigger than life aspect in some way.
That is my opinion at least.
Recording and mixing is art. Like mixing oil paints for texture and color.

Here is what you need to know. Recordings can be for elevator music, new age music, or statements about anxiety, personal or cultural. People can strike out and make statements using music that others will feel and hear. That is the point of ART.

Listen to the Beatles here with their intentional distortion.
This was no accident. This is what they wanted to sound like.
https://reverb.com/news/howd-they-get-that-sound

They had something to say. The recording is perfect. I was a teen in those days and we all had this confusion and anxiety going on. There were the riots, the women's rights marches as well as the draft. This recording cuts. It is distorted and grinding. This recording knocked us over. This is not transparent or anything nice. The times were anything but nice. JFK, Bobby and MLK had been shot to death. This recording connected to us.

So, you might ask yourself, do you want to make elevator music or do you want to use your knowledge of recording do more, to make a statement. To do that you have to have a working understanding of how to use the tools in recording to make your statement... even the most basic tools.

Just a thought.

Jim Moss

From intermodulation effects that you don't see. From slew limiting. From transient effects like power supplies sagging. Maybe it breaks out into oscillation after running for an hour but you never notice that on a short test. What you describe is a very good test, but not a universal test. There are a lot of tests that can measure that stuff, but you need to know to use them first.

Exactly! It's NOT a measurement of anything scientific. It's a measurement of what you're hearing. There might be plenty of effects that you can measure, but if you can't hear them, they aren't worth worrying about.

Okay, old guy story...
When I was a kid, amplifiers all had the same topologies and the same basic distortion spectrum as a result. People used full-power THD to measure differences between amplifiers and it was great. Then a generation of high-gain solid state amplifiers came along which had great full-power THD measurements but sounded terrible.

The industry split mostly into the Julian Hirsch camp which claimed that the amplifiers must be great because the measurements were so good, and the John Atkinson camp which claimed that all measurements must be useless because the amplifiers sounded so bad.

In the end... what happened was that people like Marshall Leach and Matti Otalai pointed out two things: first of all these amplifiers had crossover distortion issues and consequently although the full-power THD numbers were great, the THD at actual listening levels was terrible. Secondly they pointed out that the systems had transient issues which in the end were issues due to slew limiting somewhere in the circuit. (Sadly they did this in different ways and never stopped fighting one another about which was the best way to measure the effect, when in fact they had two measures of the same thing.) ONLY UNTIL THIS HAPPENED DID ANYONE FIX THE PROBLEM. Because of this, we now have solid state amps that sound good.

The problem isn't with listening. The problem isn't with measuring. The problem is that you have to connect the two.

Right. Transparency is not a scientific measure. And it won't ever be until we can get a perfectly accurate model of the human hearing system.

But because we USE the human hearing system for actual listening, it's the only measure we have to make overall evaluations of the system. It's not a very consistent or reliable measure, it's true. This is unfortunate, and it's why we need better models of the human hearing system so we can have better measurements.

You bet! This is why we need objective measurements! Without measurements, you can't be sure that your listening test is actually working. But without listening tests, you can't be sure that you are measuring the right thing!

Until we have a perfect model of human hearing, we're going to have this problem. We are far, far closer to it than we were when I started out. It is, I think, the number one issue in the audio world.
--scott

One of the things about the U67 is that it does not aggressively squish on peaks the way the U47 and many other tube condenser mikes of that era did. That seemed like a good thing to me, but these days people are less likely to want that.
--scott

...which sums up my experience with vintage tube mics quite nicely and which led me to keep but a single u67 from a small collection (and which, after my mic doctor spent some time fixing various issues, sounds possibly as good as new/better than ever before to my ears)!

Hi deedeeyeah.

Sorry to see you set upon in the "Curious about total analog recording" topic. Some people cannot discuss or accept others' opinions, they just want to throw stones and call names.

Re. tube mic pre's, I had to do a presentation a couple of months ago and dug out some recordings made with valve mic pre's mixed straight to stereo in a valve mixer, both made by EAR (Tim de Paravicini). I had stopped using Tim's setup because it was too heavy (80kg for the mixer), but when I heard the sound it made me get the valve pre's out of the garage for my next job.

A carefully chosen all-valve system (from mics to 2ch analogue mix) does deliver more weight if your source content has energy down there - like a symphony orchestra, Steinway D grand piano or big organ.

Transformerless solid-state pre's and phantom-powered transistor mics sound lightweight in comparison. Maybe it has something to do with how phantom-powering gets managed both in the mics and pre's. Maybe it is something to do with the mixdown being all-analogue rather than done digitally in a DAW. Hard to say.

As a tip: if you get a chance, try the Thinking Man's version of the Neumann U67 - it is called a M269c. Looks like a U67 but has an AC701 valve instead of an EF86.

I was just going to post in another thread that in looking over schematics of many preamps, mixers and interfaces, that the phantom circuitry often struck me as under-engineered, compared to the rest of the circuits; they often to get short-shrift, for some reason. Insufficient current, minimally filtered, etc.

I've also found that my SS pres sound 'smaller' than the tube units - and mine are all transformerless, so it's not 'iron' I'm hearing.

hi mr f

thx for your comment on the thread which was closed (just as i was typing in a response to about a dozen of posters)...

as mentioned elsewhere, i got to use mainly tube ldc's (for mains and spots) when assisting jürg jecklin from the late 70's into the early 90's; he even built a protoype tube preamp for the violinist with whom i played in a band with amplified instruments...

except for a u67 which i kept from that time, i sold all my tube mics, as well as most any analog gear (save a few preamps and channel strips): less for 'sound' reasons but for practical reasons.

regarding 'sound', there's no denying that using tube gear, high headroom class-a gear, dozens of transformers (and maybe even tape) etc. does shape the 'sound' in specific and sometimes mysterious ways which gets often described as warm, natural, having weight etc...

...but my taste has evolved towards a leaner, more transparent sound image (which has led me to use a coincident main mic system more often - and then of course at least a pair of ambis). also, if there's something that i'm occasionally missing from an über-clean capture by digital mics (or other modern gear), i've learned to compensate with digital tools. and i'm using way more mics than in early years so...


...albeit i'm using a vastly different approach and newish gear, the 'sound' i'm getting may not be that far from results i got 30-40 years ago - kinda ironic, innit? :-)

Nothing wrong with irony in the right place.

There is plenty of irony to detectable in Glasgow at COP26, but few politicians find it easy to laugh at themselves.

Tube mics are a pain in the neck with their cables, connectors and power-supplies - and the price of replacement AC701 and VF14 tubes. I still like the way they sound on a good day on a big orchestra - bit of a pest.

Classic TF understatement.

To Tony directly - did you ever aquire any of the Decca M50s that were converted to FET?

Interesting comments about the low end and weight possibly due to phantom power.

I have just received my 4006TL back from Rens with his replacement 48v circuit board (these still have to hang in the concert hall, otherwise I would have gone for the 60v). I understand that Rens improves the delivery of phantom in the 48v board.

Its the bass and low end that has been clearly transformed. Recording the 32 Beethoven sonatas at present and have never heard the piano sound so huge and brassy in the low end. Wonderful stuff.

….and, if I can join the queue of questions to TF…would the mooted Rode TFM50 ‘modern valve’ mic encompass the best of the old character without the maintenance drawbacks…and if so, why hasn’t it claimed a sizeable place in the market (yet) ?

Yeah, the U47 that I used sounded weird. I own a U47-fet. That pretty much sounds like the U87 to me. It just has issues with the pins that I have to keep fixing.

Jim Moss

Heterodyning or Intermodulation Distortion can occur when two or more signals are mixed through a non-linear device. LIKE YOUR EAR. Your ear is a nonlinear device where heterodyning (intermodulation distortion) does occur. Messy indeed.

Transient response is one of the performance requirements any Pro Audio vacuum tube design should have built in. A lot of it depends on the audio transformers used. There are many things I had to consider when designing this preamp. LOTS of things. Safety issues included.

Sagging power supplies are sometimes there on purpose, designed in. I thought about doing that, but decided against it. My preamp power supplies are fully regulated, even the HV B+. I use a higher than usual High voltage to get the sound I wanted. A lot of guitar amps use starved plate designs. It is a sound. I just wanted a much more robust design. My design can maintain the proper design internal voltage on the 120 Volt setting anywhere from 80 Volts to 135 Volts. I am sure it will handle higher and lower voltages than that. I just don't claim that. Same for the 240 Volt setting.

I have been recording field festivals where the power line voltages went down to 80 volts. They were then adjusted with a Variac.

I leave the studio on 24 hours at a time with no oscillation, within or outside the audio bandwidth. The proper design of a HV power supply takes that into consideration. That is all you need to have a power supply turn into a UHF oscillator. That is just good design. Also, the ability to operate for days with all the vents closed off and the room temperature at 90F is an important thing to design in. I had great mentors I could go to for advice. They kept me out of trouble. Maybe even had me over build too much, but better safe than sorry.

In some of your comments you seem to be talking about solid state preamps or HIFI systems. I am not commenting on them.

Jim Moss