royer vacuum tube ribbons?

[Simon B]

Going through audio technology and saw a new product. R-122v a vaccum tube ribbon mic
Has anyone used one, and does anyone know anything about them? I thought the voltage coming from the tube would almost instantly break the ribbon? I know royers are meant to be a very versatile ribbon mic, I havent used one and dont know much about royers. although a few reliable sources have said they take a larger amount of SPL then most ribbons.. I dont know I just cant imagine what a tube ribbon mic would sound like.
any thoughts?

[Howard Jones]

The ribbon is the transducer element and the voltage/current coming from it feeds the valve, not the other way round. The input signal to a valve is applied to the cathode which is at a low voltage. The supply rail voltage is very large and is applied to the anode.

A valve is an amplifying element like a transistor or FET.

[mfdu]

i would'a thought the valve circuitry would save the ribbon from potential damage by phantom power (my greatest fear) and also ensure optimum mic/preamp impedence matching.

and anyway - it's gold, baby!!!!

chris.

[Chris H]

On my STC ribbon, its the transformer that protects the mic from phantom power. Still i avoid phantom power just in case.(This mic is actually a multy pattern with a dynamic and ribbon element.)

[Howard Jones]

You are all over-generalising the circuitry inside any given mic. It is, however, very wise to assume that, unless you know better, you must not apply phantom power to a ribbon mic, given the damage that might occur and the cost of rectifying it.

Phantom power is applied to pins 2 and 3 of the output connector (if it is an XLR) of the mic or its power supply. This connector is where, in German terms, the modulation comes out - we would say it's where the audio comes out. How the mic converts from an acoustic signal to an electronic audio frequency signal varies greatly from model to model.

Phantom power is only there (originally) because the capsule in a condenser microphone requires a large polarising voltage.

[Simon B]

I would like to run a few things past you people in the know, I am going to explain my understanding of a tube and would appreciate many corrections please.

A tube in audio terms, generally amplifies the signal? while adding a harmonic distortion that is pleasing to the ear..... I understand there are many different types of tubes using a guitar amp as an example 12ax7 are used by most amp makers for preamps because of the gain they make in the preamp stage, yet there are alot more musical tubes that could be used for less gain make up but better harmonic distortion.

so with a ribbon mic having a tube. it is amplifies the output of the signal and the ad suggests 29 db of gain. so then to remain true to the ribbon characteristic you could only hope that a tube with not much harmonic distortion would be used......

does anyone know which sound they would be characteristically trying to acheive? a ribbon mic with a gain make up, or a ribbon mic with the harmonic distortion of a tube, or a tube sound captured by a ribbon component?

any corrections to my naive state of mind would be apreciated

[Howard Jones]

Simon, you have opened a giant can of worms here... No doubt, every man and his dog will weigh in with all the usual stuff from the sublime to the ridiculous about valves, harmonic distortion, odd-and even-order harmonics yada yada yada.

Therefore, I will not say very much except this: back in a golden era when designers thought that audio should strive for high-fidelity recording and reproduction, ALL amplifying elements including valves formed part of a circuit that was definitely not trying to introduce distortion of any kind - quite the opposite. When solid state devices came along, they were embraced by those designers for a multitude of reasons including better reliability of operation than valve circuits, less heat because the voltages required were lower and less distortion.

The only reason that a company (other than a guitar amp maker - I'll come to this shortly) releases a product containing a valve is because they are looking for a certain sonic signature for that product or because of a push from an anxious marketing department. No company releases a product with a valve in it because they see that as the way forward to a lower distortion circuit.

Microphones are, in theory, desired to faithfully reproduce what goes into them. They are an intermediate factor in the chain between the recording studio and the listener's ears. None of this applies to electronic music made on guitars - these devices are producing the original audio themselves, not trying to capture audio made by another device. Therefore, it is a highly moot point whether a guitar head should be a valve or solid state device.

I'm no guitarist but I have no doubt that a Strat played through a valve amp sounds different to the same Strat played through a solid state amp. In these cases, the different sounds tend to become part of the signature sound of a player, particularly if he or she becomes famous. Once a player has developed a sound, it is usually a combination of using a given guitar with a given amp turned up to a given volume with a given footpedal thrown into the equation for good measure.

In such a case, it doesn't matter if a valve amp, or a solid state one for that matter, distorts to buggery - it is simply part of the sound that the guitarist has been searching for and is presumably happy with. Of course, if the guitarist is not wanting distortion then there is a problem. Which leads us back to the standard definition of distortion being any unwanted signal.

In theory, if we are using a microphone and it introduces an unwanted signal i.e. something that wasn't there in the first place, then we regard such a microphone as performing poorly. In practice, it is not that simple as people sometimes find the distortion attractive. However, it is important not to confuse the general principle that a mic, voice channel etc etc should pass signals through faithfully without distortion whereas the question is irrelevant for guitar amplification.

My experience is that people often confuse these 2 issues. See, I told you I didn't have much to say...

Howard

[JulienG]

Simon, you have opened a giant can of worms here... No doubt, every man and his dog will weigh in with all the usual stuff from the sublime to the ridiculous about valves, harmonic distortion, odd-and even-order harmonics yada yada yada.

How about leaving it at:
"Valves do stuff to the signal, a lot of people like that stuff"

[Howard Jones]

Well, Julian, that depends on whether you want to remain ignorant of the larger issues - the context from which the industry as it now is derived.

I've already been surprised at the lack of awareness in this thread about some pretty basic stuff. Simon kicked this thread off by saying, inter alia, " I thought the voltage coming from the tube would almost instantly break the ribbon?". Sorry, Simon, but that was a naive statement - why would a manufacturer produce a product that would do that?

But that's just a simple misunderstanding of how the mic works. Much more serious is the cynical, even vicious exploitation of the market indulged in by a well-known manufacturer of cheap clone products who has produced a model supposedly based around a valve circuit. There's a valve in there all right - made to look like it's working by having 3 yellow LEDs glowing away in back of the valve.

I suggest that this sort of corruption wouldn't occur if [a] people took steps to inform themselves more thoroughly about how this stuff works [b] made informed decisions about what proportion of their equipment should be valve-based and [c] had access to magazines that dared to publish negative equipment reviews when appropriate.

Howard.

[JulienG]

Well, Julian, that depends on whether you want to remain ignorant of the larger issues - the context from which the industry as it now is derived.

True, I considered adding an even more flippant remark to my last post but decided against it.

But that's just a simple misunderstanding of how the mic works. Much more serious is the cynical, even vicious exploitation of the market indulged in by a well-known manufacturer of cheap clone products who has produced a model supposedly based around a valve circuit. There's a valve in there all right - made to look like it's working by having 3 yellow LEDs glowing away in back of the valve.

Now while they are pretty bad there are other manufacturers who have done similar (tube in the power supply not signal path etc). However what little point I had in my last post stands, if it sounds good what's the problem? If it doesn't sound good then why are you buying it?
If a manufacturer needs to do that sort of then I'd treat it as a likely reflection on the sound quality - but it could also be a Bling thing to attract a market, that was Korg's justification for their own backlit valves

I suggest that this sort of corruption wouldn't occur if [a] people took steps to inform themselves more thoroughly about how this stuff works [b] made informed decisions about what proportion of their equipment should be valve-based

And which bits, valve mics, valve preamps, valve console, valve outboard, a pre-transistor 1/2" deck?
If you're going to the effort, put a valve where it'll give the most benficial effect, that may be in the mic, or may be in say a compressor.
Then theres things like http://www.vintec-audio.de/vintec/index_E.htm

and [c] had access to magazines that dared to publish negative equipment reviews when appropriate.

Yes, but better no reviews then fake glowing reviews, some publishers still don't understand that is a big alienator of your audience.

[Howard Jones]

"If you're going to the effort, put a valve where it'll give the most beneficial effect.. "

My point was that there is no area where a valve has a beneficial effect - technically speaking. People buy valve gear for sound colouration. So long as they understand that and don't kid themselves, I'm happy. Remember, everything I've written has been in the context of the original post which to me threatened to career off down the path of good and bad distortion. Forget it.

"Yes, but better no reviews than fake glowing reviews, some publishers still don't understand that is a big alienator of your audience"

I'm not aware of anyone who publishes bad reviews when required. Publishers would apparently rather alienate their readers than their advertisers.

[mfdu]

for my money, if the valve is part of a pre-stage then that would possibly mean there is protection from phantom.
yes my only ribbon (a shinybox 46) has an output trannie in it, but phantom will still kill it. so there's a possible benefit to the royer.

also, there's the issue of output level. if the tube stage raises the output, then the console pre won't have to work as hard, possibly reducing noise.
my ribbon requires 65dB of gain on a voice with decent projection.
for ambient use, i then need to push on +10 with the channel fader as well - this raises the noise floor, funnily enough. and now i'm at maximum available analogue gain.
if the tube stage brings the mic more into line with the output level of a dynamic, then that'd be handy.

ignoring the actuallities like "how does it sound" of course. . . i bet it's different to my shinybox.

chris.

[Kris]

"also, there's the issue of output level. if the tube stage raises the output, then the console pre won't have to work as hard, possibly reducing noise."

forgive my ignorance but i would have thought it would make no difference where the gain came from. Gain is gain, be it from the tube or from the desk. Either way, you boost gain somewhere you're gonna get more noise floor.
[/i]

[mfdu]

yeah yeah

what i mean is this - console gain at max (65dB) and fader at +10 is going to be amping the self-noise of the mic, and any introduced noise in the line by 65dB +10 (and any additional gain out of a compressor or whatever.

compare that to the required gain on a condensor or dynamic, huh? maybe 35-45dB with fader at unity.
the simple fact is you need to wind on so much gain for a ribbon that the gain amplifies and potentially introduces noise.

cool?

so what is the output sensitivity and self-noise of the royer valve ribbon compared to an SM57 (

[Linear]

forgive my ignorance but i would have thought it would make no difference where the gain came from. Gain is gain, be it from the tube or from the desk. Either way, you boost gain somewhere you're gonna get more noise floor.
[/i]

Where the gain comes from is super important. Proper gain staging is something (sadly) that many people recording these days have absolutely no idea about.

What you really want to do is apply as much gain as the next stage can comfortably handle as early up the chain as possible. It makes sense because each stage adds noise as well as amplifying existing noise, and this is particularly evident at the summing stage.

When recording to tape this is important because it has a dynamic range of around 65dB, so a puny signal going to tape will be noisy when if or when you compress it later.

I'd imagine proper gain staging is important for digital systems as well, but I don't know enough about that to comment.

Chris

[David W]

[quote="Howard Jones"]"

I'm not aware of anyone who publishes bad reviews when required. Publishers would apparently rather alienate their readers than their advertisers.[/quote]

Well put.
I used to buy 3 different mags religiously.
Havn't bought one now for over a year and find information on forums like these to be much more benificial.

[mfdu]

hi linear

sadly, with the prevalence of digital recording i think the art of gain-staging has been put to one side.

if you've boosted the noisefloor in the signal on it's way to hdd, then just eq or draw it out. that won't hurt, will it? (rhetorical question)

gain staging? just jam the faders (if they even have faders) straight up to +(max) and then crank on the gain so you're just below clipping. thats optimum signal level, innit? (again, rhetorical)

"fix it in the mix". but now in areas that would have freaked even the most laconic/lax engineer of yore.

hmph.

chris.

[rob]

gain staging....

the fundamental importance is to identify the difference between a "gain" pot and an "attenuator". Both can turn the level up and down, only the circuitry around a "gain pot" can change the signal to noise ratio.
Faders on most consoles are just attenuators, the signal to noise ratio stays the same regardless of the postion of the fader.

[rick]

why is it i always forget to log in on the days where something interesting is said on this forum


what about this for an idea

the great thing about a ribbon microphone is it is impossible to create a square (or duplicate) one with a ribbon mic they cannot clip , the up shot of that is ribbon mics sound smooth on crunchy distorted guitars !

the down side is if you hit them too loud they dont clip they tear up and thats the end of the ribbon

the transformer in a ribbon mic is essential to convert the ribbon element into an impedence strong enough to drive an audio lead without losing tone.

the cool thing about the royer 121 (the original version) was it is designed to handle loud levels without tearing up

the down side is if you want to use it to record something from a distance
you need a very good mic pre to give you 55-70 db of gain and one that is matched to the impedence of the royers transformer

so by public demand they produced a mic that had internal fet eletronics that increased the gain so you could use them to greater effect on distant miking AND matched the impedence of the ribbon perfectly so it could
run a long load without losing tone

i am not sure where all this talk of transformers being used to protect against phantom power comes in , but the thing is they dont..

phantom is not a problem in a ribbon mic unless the earth wire somehow shorts out ( like in a dodgy lead!) so people are afraid of an accidental short not a phantom power splat

its a pretty obvious move for royer to replace the fet (solid state) electronics in the ribbon mic with tube ones , and i am sure it would have been by request.

so now they have a tube powered ribbon mic that puts out such a good level any old mic pre will cope
and if the ribbon makes it sound warm, the tube makes it sound warm and the gold coatiing makes it feel warm

well marketing genius X 3
i say


i have a lot of tube devices so on this subject i am very certain, beware of ANY tube device that claims to "Add tube warmth'

excluding guitar boxes ( i have heaps of them too !) i do not use tubes for distortion charateristics, in fact my tube gear doesnt do all that 2nd harmonic garbage or warmth or whatever it is they model in plugins

in my studio
"tubes are super clean minimalistic amplifiers in little glass jars"
this is what all the classic audio gear was aspiring towards.

if i read one more comment about glorious 2nd harmonic distortion out of a vintage studio device i will be forced to .....
well sigh about the marketing genius of computer companies

[Simon B]

that almost sounds like you now like royer?

Howard I thank you for clearing alot of things up for me. I know I made a lot of naive and illinformed statements in this thread and on this phorum, but that being said that is why I ask alot more questions then answer them on threads....

[rob]

just to clarify something Rick

you said "the transformer in a ribbon mic is essential to convert the ribbon element into an impedence strong enough to drive an audio lead without losing tone. "

this is not quite correct. The ideal way to drive a long line without "losing tone" is to drive it with as low an impedance as possible. And by a long line i don't mean tens of kilometres long...that is a different ball game.

The "raw" output impedance out of a ribbon element before the transformer is added is very very low and would be ideal for driving your mic cables. But ( and this is why a transformer is added ) the level is also very very low, far too low for a mere mic-pre to bring up to a useable level. Thus the transformer gets added to step up the level and whilst it still ends up at a low level ( compared to other mic topologies ) it gets into the ball park for mic-pres to deal with.

Why not use a transformer with a higher step up ratio to give more level you ask? Well then this would raise potential problems driving the long mic lead causing tone loss and also it gets harder to make a transformer that physically small that can give a high step up ratio with out producing frequency response problems and ringing. Also your average mic-pre would end up presenting the incorrect load to this transformer for it to do it's thing.

Like most things in life ...it's a trade off.

So by adding electronics into the ribbon mic wether a fet or tube, gives the designer more options to trade off. In the case of the Royer they can give you more output level whilst still maintaining a suitable and typical output impedance.

BTW i was working a tube unit yesterday...turning a Byer tape machine audio module into a mic-pre / DI....I had lots of 2nd harmonic distortion happening...up to 5% at hot levels

[Howard Jones]

"I'd imagine proper gain staging is important for digital systems as well, but I don't know enough about that to comment"

Gain staging is as important in digital systems as analogue, although you really only have to consider a couple of steps as opposed to many in analogue chains.

This is an important subject on which I will try to contribute a post tomorrow - the silly season is upon me and time does not permit just now.

"Both can turn the level up and down, only the circuitry around a "gain pot" can change the signal to noise ratio"

This isn't correct either. Because an attenuator turns down the signal whilst the noise floor remains the same, the S/N is ergo reduced because you are reducing the dynamic range of the signal. If you turn the attenuator down so that the signal is almost cut off, the S/N ratio will be very small. At the top of the attenuator's range, the S/N ratio will be the maximum it can be for that part of the circuit.

What doesn't change for this situation is the noise which remains at the same level no matter the position of the attenuator. In an active gain stage, the situation is that the noise can be increased. So can the signal, so the S/N ratio calculation is a bit more complex. In both situations, however, the position of the knob will affect the S/N ratio.

Howard.

[rob]

yes Howard is correct about attenuators. But this is when including the amplifier that follows the attenuator's noise contribution. This is the constant noise floor. I should have clarified that i was just referring to the attenuator itself with regard to it's affect on the signal to noise of the incoming audio. Since a common implementation of an attenuator is the faders on a console the constant noise floor is largely determined by the mix buss / mix amplifers and in this situation the best signal to noise is achieved with the faders full on.

So in general terms the best signal to noise is achieved with minimum gain ( at the mic-pre ) and minimum attenuation ( fader full on )
But we all know this yeah!

And yes the noise gain of a mic-pre is not necessarily directly proportional to the signal gain of the mic-pre. This is a complex area of pre-amp design.

[mfdu]

dealing with my studiomaster series 5
(pause for everyone to stop laughing)
i certainly know that my noisefloor ramps up dramatically with the last 10db of gain - the pre just isn't in it's happiest area.

i've taken to adding a gain stage at the insert point. i am using my what? opto compressor clone which has about 30db gain itself (have used as for a dynamic mic pre in the past).

this allows me to keep the channel gain playing nicely, the fader at unity and build the smooth ribbon signal up by passing it through an OEP 1:1:6.45:6.45 trannie with a fraction of opto compression.

thats my work around which has worked on cello, double bass, voice, distant acoustic guitar. it's the only way i can build enough clean gain to use the ribbon in ambient situations.

i was looking into builing or buying (rode d-plug) an inline phantom-powered line-driver to give a flat 20db or so boost to the ribbon.
putting it after even 1m of good cable increased noise massively.

well, there you go.

chris.