Advice needed for cello CD

I've never done it myself. I guess i'll just have to try it and see...

The only reason to consider daisy-chaining in this situation was because of an impedance mis-match and the resulting reduction in level. But there will also be a rolloff of the bottom end of the Royer if you use the Sebatron, or anything else that is less than 1500 ohms.

My advice is try the Sytek. If you cannot get enough level from that then plan on making up the gain in your DAW or go to plan B with different mics.

Why they do not pubish input Z is a mystery, and if you cannot confirm that it meets the needs of the Royer then you are starting your project under less-than-ideal circumstances.

Any chance you could get a Millennia?

Rich

Found out from Mike Stoica at Sytek that the MPX-4a has an input Z of 1.2 kOhms. He said that most of the poeple asking him impedance questions are doing so because they are about to use it with an SF-12. He also said that that the SF-12 will work fine with the Sytek and he has no idea how Royer came up with the 1.5 kOhms figure.

Can anyone explain the science behind impedance matching to me or at least provide me with a link? I understand basic electrical concepts, but this I don't get.

I can't get a Millennia, but I can get a John Hardy M-1. I can't seem to find an input Z spec on that one, either. Anyone know?

The rule of thumb for ribbons is 5 x mic Z (300 ohms in the case of Royer) which equals 1.5k ohms.

Rich

Well I tried a 1.5K input Z preamp with the SF12 first and it sounded flabby on the end of the 20m cable hung from the ceiling. The Nagra V was next, 2.5K input Z and it was a bit better but not much. So I then tried the TC Gold Channel (3.8K input Z) and it was much better, tighter bass, more extended top end, then I tried a AMEK 9098 (5.5K input Z) and it was even better again. These impedance figures were measured and not read from a spec.

I attributed the improvement to less ribbon loading as these preamps did not exhibit this level of sound difference on condensers. I then started speaking with Fred Forssell about his JMP-1 and building a special preamp for the SF12 with a 10K input impedance, but then I got the SF24 and the problem went away.

Here is a useful link.
http://mixonline.com/online_extras/ribbon_mic_preamps/

Sonarerec wrote: Personally I would avoid daisy-chaining micpres. You are not likely to be pleased.

It isn't a problem to daisy chain mic pres, but you need to chain pres with the correct design. Many preamps are built with mutiple gain stages so you can get more gain and keep it clean. To be able to daisy chain preamps, you need to have a preamp that also has a DI/Hi-Z input. You don't want to plug the output of a preamp into the input of a second preamp.

I actually do this with the Vac Rac preamps as they are a bit light on the gain sometimes with some mics and program material (ie a ribbon mic and a classical guitar). I'll gang 2 pairs of pres- the output of the first pair goes into the hi-z input of the second pair. I don't have to crank either one and the recording stays quite clean and sounds good.

--Ben

David, thanks for your experiences and the link. Damn. I'm sure not going to get 5 kOhms of input impedance! I wonder what the R-122s internal effective loading is? Hmmm... perhaps I should just go with the R-122s. I was also thinking Coles, but I suppose I just get into the same headache.

I use the R122's (and the SF-24) all the time and I've never had an impedance issue with them... Fantastic microphones, and the extra gain is nice too. I've put them through a couple hundred feet of mic cable easily without a single problem.

--Ben

FWIW Royer says all their ribbons are 300 Ohms. The SF24 active eliminates the impedance problem entirely. A little pricey to not end up at line level, however (IMO). The R-122 is brighter, or so I am told. What say you, Ben?

Why not use the Sytek and be done with it? And there is always the chance you may prefer a condenser mic on the cello.

Rich

I'm betting i'll get better results with the JH than the Sytek.. I just wish I knew the impedance figure.

If you look at the freq. response plots ( if you can trust that), the SF-1 and the R-122 measure nearly identically. The back of a Royer is indeed brighter up close than the front side due to the offset ribbon design, but i've used them (R-122) a couple of times and I wouldn't call them a bright mic at all.

One thing about the R-122s... hard as hell to setup a Blumlein with the possibility of changing the placement, at least with the equipment i've got. SF-12 would be nice for that reason alone.

I would say that the 122 has a touch more extended top end, but I wouldn't call it brighter. I find it to be a bit more detailed and like the SF-24 in comparison to the SF-12, I find it to have a bit "meatier" sound in the mid-range. Just seems to be a bit more there.

--Ben

Well there I go! Bugger the SF-12 and all the impedance problems. Thank you Ben.

I must say that I still find the SF12 and SF24 a tiny bit "dull" in the top end. I want to use that word cautiously, as its only when comparing the result with condensers that it stands out, but its there. I find that I add high EQ to most things I record with the SF's to get to tonal balance right.

The thing is, the Royers have some of the best midrange of any mics I have heard, and for strings, brass and vocal stuff, especially sopranos, they are completely compelling. I have played engineers some of the string quartet and trio recordings done with SF12 and SF24 with groups like Mosaiques, Aust String Quartet, Macquarie Trio and all agree that the sound is very accurate and pleasing.

But at the top of my shopping list at present is a pair of Coles 4040, which I think will be my ideal mic. They have much greater output and very extended and pronounced top end. We used one on a child's voice and on a glockenspiel and I have never heard such a rich, feathery top, tonally accurate sound before.

I simply find condensers just too crisp for a lot of things these days, maybe my middle age is catching up with me, but I am a real ribbon fan now, the recordings are more tolerable for longer listening sessions than these over bright, crisp, brittle things I hear around the traps.

I felt the same way about my SF12 for non-choral applications when using a Precision 8 micpre. Then I tried a Millennia Media. WOW. What I was really missing was transient response, and the Millennia solved that nicely.

I think many folks' ears are tired and have digititus, hence the popularity of the MKH line, the Neumann TLM170/193/U89 and Schoeps MK2.

Rich

Yesterday was the first day of the session. We will resume tomorrow, but in the meantime, i'd like to get an evaluation of my work.

Here is a very brief and rough snippet from one of the takes:

[[url=http://[/URL]="http://www.bsu.edu/…"]Beethoven Sonata #4 for Cello and Piano[/]="http://www.bsu.edu/…"]Beethoven Sonata #4 for Cello and Piano[/]

Setup:

Cello 8' in front of piano on 6" riser.
Piano rotated slightly CCW, cello slightly CW.
Piano on full stick
Main Pair: CMC6|2, 40 cm, 10' high, 1' in front of cello
Cello Spot: 4038 blumelin, 3' from bridge at bridge height.
Piano spot: MKH-80 MS, close to edge of lid in center of piano

A lot of the cello sound comes from the spot and the piano spot is mixed just enough for clarity.

So, what do you guys think?

I'm looking for a response before Friday so that I can use whatever advice you guys have for me, but if you see it after that, i'd still be happy to hear from you.

Thanks again.

Cello Spot: 4038 blumelin, 3' from bridge at bridge height.

So this is a "stereo" spot right? Two mics?

To me the overall perspective should be slightly closer and the cello is not loud enough relative to the piano. The cello also sounds a little disconnected from the piano.

So I would move the cello back closer to the piano, say 1-2 ft, and put the 4038 pair closer and a bit higher than bridge height, pointing down. Also move the main Schoeps pair a bit closer as well. Balance the Coles higher in the mix.

The idea is to get the cello balance louder relative to the piano and to connect the two a bit more, at present they sound a bit like shags on a rock.

First thoughts only, more later perhaps.

Thank you David.