Budget Phantom powered Ribbon Mic?

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dickiefunk

dickiefunk

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Hi,

I'm considering picking up a budget ribbon mic and I would like one that is Phantom powered.

After looking around for a while these are the ones I came up with :-

Samson VR88
Golden Age R1 mkIII
Karma K-6
Superlux R-102

What are your thoughts on these mics? Which one would you recommend as an alternative vocal mic for a harsh bright female vocalist?
 
I wouldn't, honestly. All the phantom-powered ribbons I've tried thus far are significantly noisier than the same ribbon elements with a transformer fed into a decent preamp. Go with an unpowered ribbon and a good pre instead and you'll be a lot happier in the long run.
 
dgatwood said:
I wouldn't, honestly. All the phantom-powered ribbons I've tried thus far are significantly noisier than the same ribbon elements with a transformer fed into a decent preamp. Go with an unpowered ribbon and a good pre instead and you'll be a lot happier in the long run.
Click to expand...

Wow I'm surprised at this!!!

What phantom powered ribbon mics have you used?

Which unpowered ribbon mics did you compare these to?
 
dickiefunk said:
Wow I'm surprised at this!!!

What phantom powered ribbon mics have you used?

Which unpowered ribbon mics did you compare these to?
Click to expand...

I've compared some of the Chinese ribbons from our group buy versus their phantom counterparts from other group buys and other non-GB sources. In theory, a phantom-powered ribbon ought to be ever so slightly less noisy than a low noise preamp, simply because there's no such thing as perfect noise rejection, and cable runs add noise.

However, in practice, a microphone selling for less than the cost of a good preamp is unlikely to have amplifier circuitry of comparable quality, and the difference in quality of the gain stage matters a lot more than the difference between putting the gain stage right next to the source and putting it at the opposite end of a typical mic cable.

I'd be willing to bet the AEA ribbon is a very different story, just because they have a long history of building great ribbon mics. Most of the ribbon mics out there, however, are made by one of a couple of Chinese manufacturers, and if those companies build active ribbons like they build condenser mics, they probably all use a single circuit design (or at best, two) that isn't well matched to the capsule. :)

I'd love for MsHilarious or Marik to chime in on this thread. They're both a lot more familiar with the details of this stuff than I am.
 
The potential advantage of a phantom-powered ribbon is that the transformer can be wound to a higher ratio, which reduces the need for an extremely low-noise amplifier. This cannot be done with a passive microphone because the resulting output impedance would be too high. The amplifier can also be very high input impedance, which reduces loading. That could be done with a mic amp (at least up to the resistance of the phantom resistors), but typically is not for no good reason I can discern (I build my mic amps with high input impedance). The AEA ribbon mic amp does that.

I've never seen an inline amplifier match what a good low-noise preamp can achieve, although it is possible in theory to get close. But most are significantly noisier. Given that a cheap phantom ribbon is not likely to exceed the performance of such inline amps, and I also understand that they aren't doing anything special with the transformer, there is no reason to prefer them.

Bottom line, if the phantom ribbon you are looking at doesn't publish a self-noise spec, avoid it. If it does, consider that the self-noise of a passive ribbon into something like a DMP3 will be 20dBA or so.

I have an old Shure 315 with a selectable-impedance transformer; I've been meaning to do a high-impedance inline amp for that but it hasn't crept to the top of the list yet . . .
 
mshilarious said:
Bottom line, if the phantom ribbon you are looking at doesn't publish a self-noise spec, avoid it. If it does, consider that the self-noise of a passive ribbon into something like a DMP3 will be 20dBA or so.
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Hi,

I noticed that the Samson VR88 has a self noise of 17dB and the Golden Age R1 18dB.
 
I thought I would muse a bit about theoretical noise performance of ribbon microphones. First, I noted above that most people are probably experiencing no better than 18dBA-20dBA.

Second, read this post by Marik:

https://homerecording.com/bbs/showpost.php?p=3540500&postcount=6

Let's ignore the issues with high ratio transformers he mentioned for a minute, and take his motor + primary figure of 0.5 ohm (round figures--also note that Marik winds very low DCR transformers himself, so that figure would not apply to his products, he is talking a typical Chinese ribbon here). He derived an effective DCR of 1.5K. That has thermal noise of -123dBV, so we'd ideally want an amp 10dB quieter than that. Thermal noise of a 150 ohm resistor (which is usually taken as the quietest possible mic amp) is -133dBV, but I think the lowest figure I've seen in real life is -130dBV (the TRP is -130dBu-A, which is -132dBV-A, or probably -129dBV unweighted). Good enough.

Back to the mic for a minute, what is its self-noise without an amplifier? If we take max possible ribbon sensitivity (without an amp) as -53dBV/Pa, then that yields self-noise of 11dBA or so, but to preserve that we need the AEA TRP or similar in terms of noise performance. Even so, 14dBA is probably more realistic for a Chinese ribbon.

Instead, if we can increase the ratio of the transformer without penalty (we probably can't, but play along), then the sensitivity of the mic increases but relative noise doesn't change any (because we step up noise along with signal). Then we no longer need a super-quiet preamp, and it's easier to do with phantom power.

I don't know the limits of that technique as I don't know much about transformer design. That's a question for Marik. Clearly my old 315 runs into problems with inter-winding capacitance because the frequency response chart shows a loss of HF at the high impedance setting. Unless Shure took into account cable losses, but I don't think they would have as that is length-dependent. Of course in a phantom ribbon we don't worry about cables, that is the point.
 
sonixx, what do you think of the trion 7000, and fat head?

those seem to be more in my current budget, as much as i'd love some of the more expensive mics.
 
aaronmcoleman said:
sonixx, what do you think of the trion 7000, and fat head?

those seem to be more in my current budget, as much as i'd love some of the more expensive mics.
Click to expand...
I do not hesitate to use either. They are different though.

Fat Head is closer to a r121.

The Trion 7000 is a bit scooped.

Here's some comparisons I did a while back:

Ribbon Mic comparison using V30 speaker.

Mic is 6.5 inches out from speaker rim aimed dead center.

Mic Order:
R121
Fat Head
Trion7000
R92
++++++++++++++++++++++++++++++++++++++++
Ribbon Mics comparison using Greenback speaker.

Mic is 6.5 inches out from speaker rim aimed dead center.

Mic Order:
R92
Trion7000
Fat Head
R84
++++++++++++++++++++++++++++++++++++++++
Ribbon Mics comparison using V30 speaker.

Mic is 6.5 inches out from speaker rim aimed dead center.

Mic Order:
R92
Trion7000
Fat Head
R84
 
I use the Golden Age R1 Mk!! and love it.
I have also owned 5 Nady Ribbon mics 4 of which were passive and each of those are far superior to my two active ribbons when coupled with the Golden Age Pre 73.
Dgatwood is not wrong.
The phantom power brings the noise floor up along with all of the good stuff.
A good preamp coupled with a passive ribbon will be much nicer.
That's not to say that the active ribbons I've owned aren't nice mics. They are.
That's for Budget Ribbons mind you but that's what the OP asked about.
There are two marvelous ribbons, one active/one passive in the "For Sale" section for $650 apiece if you want to get serious about them.
 
mshilarious said:
Instead, if we can increase the ratio of the transformer without penalty (we probably can't, but play along), then the sensitivity of the mic increases but relative noise doesn't change any (because we step up noise along with signal). Then we no longer need a super-quiet preamp, and it's easier to do with phantom power.
Click to expand...

Nope! Unfortunately the noise goes up faster than gain, so the main compromise is to make a clever balance between transformer and headamp noise contribution. It is not a trivial task by any stretch to make a low noise phantom powered active ribbon system.
Generally, it is not such a big problem to make high ratio ribbon transformer, but it requires special winding techniques, hence they are more expensive.

I am yet to see any Chinese active ribbon with... say... at least remotely acceptable noise parameters.
Better stay with passive, or prepare to pay big $$$.

Best, M
 
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