Listening impressions of Marik's new ribbon mic
- Thread starter Consul
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Brent Casey
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The guitar is a Taylor 612 going through the mics to a prototype of the new JoeMeek twin Q, with the input transformers bypassed. This outputs into a little Peavey sub mixer feeding an Echo Layla. The tracks are recorded in SoundForge 7.
The first take is recorded using Mark's ribbon with the external active impedance converter. The mic I used is a solid state E-Series prototype in cardioid, which is placed closer to the guitar than the ribbon, somewhere in the neighborhood of the 12th fret.
Second take is Mark's ribbon without the impedance converter. I used a vacuum tube E-Series prototype in figure of 8, which was placed back a few feet next to Mark's mic, but maybe a foot off to one side (the neck side of the guitar) so as not to interfere with the ribbon.
On the ribbon mic tracks, a high pass filter is engaged on the Meek, since the overhead door of the warehouse was open and a breeze was coming through the building.
It was a real hoot to have Marik here. We had a good time that was in no small part due to Mark himself, his loopy mechanic, Alan Hyatt, Guinness Stout, Apex Surplus, Tony and Michael at Stephen Paul Audio and Reid Mason of PMI for driving to his house to pick up the Taylor.
Brent Casey
The first take is recorded using Mark's ribbon with the external active impedance converter. The mic I used is a solid state E-Series prototype in cardioid, which is placed closer to the guitar than the ribbon, somewhere in the neighborhood of the 12th fret.
Second take is Mark's ribbon without the impedance converter. I used a vacuum tube E-Series prototype in figure of 8, which was placed back a few feet next to Mark's mic, but maybe a foot off to one side (the neck side of the guitar) so as not to interfere with the ribbon.
On the ribbon mic tracks, a high pass filter is engaged on the Meek, since the overhead door of the warehouse was open and a breeze was coming through the building.
It was a real hoot to have Marik here. We had a good time that was in no small part due to Mark himself, his loopy mechanic, Alan Hyatt, Guinness Stout, Apex Surplus, Tony and Michael at Stephen Paul Audio and Reid Mason of PMI for driving to his house to pick up the Taylor.
Brent Casey
G
Guest
Guest
[quote author="Marik"]Finally I am back home, so as promised, here are some files from that session. As Consul and Nat have said, the ribbon mic was
Marik,
nice mic, but recordings are so much edited and unusual for
mic analysis /i.e there is no residual noise/. But one can hear some low frequency resonancy,
Your ribbon is veryvery soft loaded with Lundahl transformer.
To solve it:
acousticaly - stretch the ribbon in the clamps more.
electricaly - use mumetal ribbon transf. may be Lundahl.
possible it have lower self inductancy and you can resonancy shift to
typical ribbon 40-50 Hz
xvlk
P.S. look at my avatar, it can be usable for you. /but only if you
have bridge finished
/
Marik,
nice mic, but recordings are so much edited and unusual for
mic analysis /i.e there is no residual noise/. But one can hear some low frequency resonancy,
Your ribbon is veryvery soft loaded with Lundahl transformer.
To solve it:
acousticaly - stretch the ribbon in the clamps more.
electricaly - use mumetal ribbon transf. may be Lundahl.
possible it have lower self inductancy and you can resonancy shift to
typical ribbon 40-50 Hz
xvlk
P.S. look at my avatar, it can be usable for you. /but only if you
have bridge finished
/Marik
Well-known member
>recordings are so much edited and unusual for
mic analysis /i.e there is no residual noise/.<
I don't really understand what do you mean by that, as there was no any editing done (EQ, splices, compression, etc.) Only short fades in and fades out.
>But one can hear some low frequency resonancy,
Your ribbon is veryvery soft loaded with Lundahl transformer.<
It is interesting that you paid attention to this, as an impedance matcher
(the way it is now--needs more work :grin: ) makes the ribbon essentially unloaded with reflected impedance.
Listen once again to the second ribbon track (without impedance matcher) and you will see what I mean.
mic analysis /i.e there is no residual noise/.<
I don't really understand what do you mean by that, as there was no any editing done (EQ, splices, compression, etc.) Only short fades in and fades out.
>But one can hear some low frequency resonancy,
Your ribbon is veryvery soft loaded with Lundahl transformer.<
It is interesting that you paid attention to this, as an impedance matcher
(the way it is now--needs more work :grin: ) makes the ribbon essentially unloaded with reflected impedance.
Listen once again to the second ribbon track (without impedance matcher) and you will see what I mean.
Marik
Well-known member
[quote author="Brent Casey"]
It was a real hoot to have Marik here. We had a good time that was in no small part due to Mark himself, his loopy mechanic, Alan Hyatt, Guinness Stout, Apex Surplus, Tony and Michael at Stephen Paul Audio and Reid Mason of PMI for driving to his house to pick up the Taylor.
Brent Casey[/quote]
It was a real pleasure to meet such great guys like Brent himself (and spend wonderfull evening talking about mics and other things, having Guiness in Fire House--pity, they closed at midnight :grin: ) and Alan. Also, Tony and Michael are awsome guys. Of course, I was in awe even thinking about going to Stephen Paul's Lab.
:guinness: :guinness: :guinness:
It was a real hoot to have Marik here. We had a good time that was in no small part due to Mark himself, his loopy mechanic, Alan Hyatt, Guinness Stout, Apex Surplus, Tony and Michael at Stephen Paul Audio and Reid Mason of PMI for driving to his house to pick up the Taylor.
Brent Casey[/quote]
It was a real pleasure to meet such great guys like Brent himself (and spend wonderfull evening talking about mics and other things, having Guiness in Fire House--pity, they closed at midnight :grin: ) and Alan. Also, Tony and Michael are awsome guys. Of course, I was in awe even thinking about going to Stephen Paul's Lab.
:guinness: :guinness: :guinness:
G
Guest
Guest
[quote author="Marik"]>recordings are so much edited and unusual for
mic analysis /i.e there is no residual noise/.<
I don't really understand what do you mean by that, as there was no any editing done (EQ, splices, compression, etc.) Only short fades in and fades out.
It is for first first group of recording /on the side 1 of this posts/
there was perhaps some noise reduction.
Second group of recording is O.K.
>But one can hear some low frequency resonancy,
Your ribbon is veryvery soft loaded with Lundahl transformer.<
It is interesting that you paid attention to this, as an impedance matcher
(the way it is now--needs more work :grin: ) makes the ribbon essentially unloaded with reflected impedance.
Listen once again to the second ribbon track (without impedance matcher) and you will see what I mean.[/quote]
To load-unload ribbon in the preamp have effect on the high end
and general to the sensitivity which falls./look at your BBC monograph/ = it resistance control.
But ribbon is really loaded with ribbon matching transformer inductancy.
Ribbon sees it via gyrator as compliancy. This shifts ribbon first
resonancy up and up to the acoustic band and make ribbon mic
more LOW NOISE INSENSITIVE. Look at freq. diagrams of Bayers
and Coles commenters mic.
Some example from my recent work. I have ribbon unit under plexiglass
jar. If I had ribbon without connected input transformer and I slowly puts
the jar upon the ribbon, I can see ribbon vibrations.
If I connect transformer to the ribbon, vibrations are invisible.
xvlk
mic analysis /i.e there is no residual noise/.<
I don't really understand what do you mean by that, as there was no any editing done (EQ, splices, compression, etc.) Only short fades in and fades out.
It is for first first group of recording /on the side 1 of this posts/
there was perhaps some noise reduction.
Second group of recording is O.K.
>But one can hear some low frequency resonancy,
Your ribbon is veryvery soft loaded with Lundahl transformer.<
It is interesting that you paid attention to this, as an impedance matcher
(the way it is now--needs more work :grin: ) makes the ribbon essentially unloaded with reflected impedance.
Listen once again to the second ribbon track (without impedance matcher) and you will see what I mean.[/quote]
To load-unload ribbon in the preamp have effect on the high end
and general to the sensitivity which falls./look at your BBC monograph/ = it resistance control.
But ribbon is really loaded with ribbon matching transformer inductancy.
Ribbon sees it via gyrator as compliancy. This shifts ribbon first
resonancy up and up to the acoustic band and make ribbon mic
more LOW NOISE INSENSITIVE. Look at freq. diagrams of Bayers
and Coles commenters mic.
Some example from my recent work. I have ribbon unit under plexiglass
jar. If I had ribbon without connected input transformer and I slowly puts
the jar upon the ribbon, I can see ribbon vibrations.
If I connect transformer to the ribbon, vibrations are invisible.
xvlk
Marik
Well-known member
[quote author="xvlk"]
To load-unload ribbon in the preamp have effect on the high end
and general to the sensitivity which falls./look at your BBC monograph/ = it resistance control.
[/quote]
I am not sure if we are talking about the same thing, as the reflected impedance affects the ribbon loading in the low end. Also, the ribbon works as resistance controlled system at the frequencies below its tuning resonance (also, there air loading is important factor due to air viscosity in the gap between ribbon itself and magnets), and above is a mass controlled system.
To load-unload ribbon in the preamp have effect on the high end
and general to the sensitivity which falls./look at your BBC monograph/ = it resistance control.
[/quote]
I am not sure if we are talking about the same thing, as the reflected impedance affects the ribbon loading in the low end. Also, the ribbon works as resistance controlled system at the frequencies below its tuning resonance (also, there air loading is important factor due to air viscosity in the gap between ribbon itself and magnets), and above is a mass controlled system.
Marik-
Have you considered using a common-base amplifier for impedance conversion? Here's a link that uses a common-base amplifier as a pre-pre-amp for a moving coil phonograph cartridge (kind of the same problem as a ribbon mic, very low impedance) -
http://homepages.tcp.co.uk/~nroberts/article64b.pdf
might give you something to think about.
Have you considered using a common-base amplifier for impedance conversion? Here's a link that uses a common-base amplifier as a pre-pre-amp for a moving coil phonograph cartridge (kind of the same problem as a ribbon mic, very low impedance) -
http://homepages.tcp.co.uk/~nroberts/article64b.pdf
might give you something to think about.
G
Guest
Guest
[quote author="Marik"][quote author="xvlk"]
To load-unload ribbon in the preamp have effect on the high end
and general to the sensitivity which falls./look at your BBC monograph/ = it resistance control.
[/quote]
I am not sure if we are talking about the same thing, as the reflected impedance affects the ribbon loading in the low end. Also, the ribbon works as resistance controlled system at the frequencies below its tuning resonance (also, there air loading is important factor due to air viscosity in the gap between ribbon itself and magnets), and above is a mass controlled system.[/quote]
You are absolutely right. But only without ribbon transformer.
(velocity) Ribbon mic really have two significant high falls.
First is determinet by width of the magnet system Magnet acts
like the baffle and stops ribbon velocity in high frequencies /10 kHz/.
But ribbon mic transformer is very upward and his high resonancy is not so high. But second fall occurs at low response and is not interesting.
You can hard - resistively - damp microphone by 600 ohm resistor.
You will have efect of resistance controlled ribbon.
But if you have "600" ohm amp, with 6k imput impedancy, you can
only damp highs of the transformer.
But if you have really 200 ohm amp in common base or common grid, or
with miller resistance, your are O.K.
If you have 200 ohm amp with input transformer, you only make lower
shunt inductancy and higher resonancy of ribbon-transformer system.
It is equivallent to use mumetall in the mic, possibly amorphous transformer is transparent here.
xvlk
To load-unload ribbon in the preamp have effect on the high end
and general to the sensitivity which falls./look at your BBC monograph/ = it resistance control.
[/quote]
I am not sure if we are talking about the same thing, as the reflected impedance affects the ribbon loading in the low end. Also, the ribbon works as resistance controlled system at the frequencies below its tuning resonance (also, there air loading is important factor due to air viscosity in the gap between ribbon itself and magnets), and above is a mass controlled system.[/quote]
You are absolutely right. But only without ribbon transformer.
(velocity) Ribbon mic really have two significant high falls.
First is determinet by width of the magnet system Magnet acts
like the baffle and stops ribbon velocity in high frequencies /10 kHz/.
But ribbon mic transformer is very upward and his high resonancy is not so high. But second fall occurs at low response and is not interesting.
You can hard - resistively - damp microphone by 600 ohm resistor.
You will have efect of resistance controlled ribbon.
But if you have "600" ohm amp, with 6k imput impedancy, you can
only damp highs of the transformer.
But if you have really 200 ohm amp in common base or common grid, or
with miller resistance, your are O.K.
If you have 200 ohm amp with input transformer, you only make lower
shunt inductancy and higher resonancy of ribbon-transformer system.
It is equivallent to use mumetall in the mic, possibly amorphous transformer is transparent here.
xvlk
Marik
Well-known member
I am still unclear what do you mean, as input impedance of the preamp loads the ribbon through the transformer. All my experiments, as well as listening tests clearly show direct relationship between load impedance (mic with transformer) and low end response.
These days I will put it on bridge to see what actually is going on there.
RCA ribbons (about 2um thick and 2" long) are tuned to about 25 Hz. As far as I know, Coles 4040 tuned to about the same resonant frequency. I am still working on finding the "best" tuning resonanse frequency, as the best compromise between sensitivity, frequency response, resonant modes, and "musicality" of the sound.
These days I will put it on bridge to see what actually is going on there.
RCA ribbons (about 2um thick and 2" long) are tuned to about 25 Hz. As far as I know, Coles 4040 tuned to about the same resonant frequency. I am still working on finding the "best" tuning resonanse frequency, as the best compromise between sensitivity, frequency response, resonant modes, and "musicality" of the sound.
Marik
Well-known member
[quote author="dayvel"]Marik-
Have you considered using a common-base amplifier for impedance conversion? Here's a link that uses a common-base amplifier as a pre-pre-amp for a moving coil phonograph cartridge (kind of the same problem as a ribbon mic, very low impedance) -
http://homepages.tcp.co.uk/~nroberts/article64b.pdf
might give you something to think about.[/quote]
Dayvel,
Thanks for posting the link. In my mic CB connection would not be benefitial, as I already have a matching ribbon transformer and output impedance is actually on the higher side, so I basically match its impedance with lower input impedance of the pre, to avoid ribbon's loading.
Have you considered using a common-base amplifier for impedance conversion? Here's a link that uses a common-base amplifier as a pre-pre-amp for a moving coil phonograph cartridge (kind of the same problem as a ribbon mic, very low impedance) -
http://homepages.tcp.co.uk/~nroberts/article64b.pdf
might give you something to think about.[/quote]
Dayvel,
Thanks for posting the link. In my mic CB connection would not be benefitial, as I already have a matching ribbon transformer and output impedance is actually on the higher side, so I basically match its impedance with lower input impedance of the pre, to avoid ribbon's loading.
G
Guest
Guest
[quote author="dayvel"]Marik-
Have you considered using a common-base amplifier for impedance conversion? Here's a link that uses a common-base amplifier as a pre-pre-amp for a moving coil phonograph cartridge (kind of the same problem as a ribbon mic, very low impedance) -
http://homepages.tcp.co.uk/~nroberts/article64b.pdf
might give you something to think about.[/quote]
Hi dayvel, marik ant the others.
Your CB amp have too many devices.
I have idea to build CB ZEN. Here is it. (It is only
idea I have not tested it)
(You must copy link below to the browser)
http://mujweb.cz/www/xvlkxvlk/amp.gif
This CB amp have input impedance 1k and lower.
Some problem. You need G5 log tandem pot.
(G5 = 500 000 000 Ohms)
It is rare device. Perhaps you must do it from discretes.
(and you can have input impedancy as legend of it )
xvlk
Have you considered using a common-base amplifier for impedance conversion? Here's a link that uses a common-base amplifier as a pre-pre-amp for a moving coil phonograph cartridge (kind of the same problem as a ribbon mic, very low impedance) -
http://homepages.tcp.co.uk/~nroberts/article64b.pdf
might give you something to think about.[/quote]
Hi dayvel, marik ant the others.
Your CB amp have too many devices.
I have idea to build CB ZEN. Here is it. (It is only
idea I have not tested it)
(You must copy link below to the browser)
http://mujweb.cz/www/xvlkxvlk/amp.gif
This CB amp have input impedance 1k and lower.
Some problem. You need G5 log tandem pot.
(G5 = 500 000 000 Ohms)
It is rare device. Perhaps you must do it from discretes.
(and you can have input impedancy as legend of it
)xvlk
