Topic: Easiest Way to get SP-TFB-2 Binaurals into an Mbox?

[bilco]

I am brand new here, just discovered the site in the last few days.  I am not interested in stealth recording, but I am interested in recording a high quality live stereo CD of singer/songwriter acoustic based music, something like a  bluegrass group in my living room, with no amplification at all.  Just voices and acoustic instruments in a semi circle.  The recordings will probably all be made in my living room, nice high vaulted ceiling, anywhere from 2-4 musicians at a time.

I have just discovered the binaural in ear mic technique and I am amazed at how it sounds compared to the HRTF, ORTF, M/S and X/Y samples.  I will try to play back some of the binaural clips I have found on a pair speakers later on.  They would have to sound pretty bad to outweigh how great they sound through headphones.  I have done some recording with X/Y using a pair of Shure SM81s into my Mbox or into an RNP into the line inputs of the Mbox, but most of my recording has been by overdubbing a track at a time into Pro Tools LE, which is time consuming and never sounds as good or anywhere near as realistic mixed as what I am hearing in the binaural recordings.  Time to make some spontaneous recordings with friends the old fashioned way, live and head on.

I have spent the last 2 days reading posts here about the different flash recorders and Binaural and HRTF mics that are available.

I am going to go ahead and get the SP-TFB-2 mics to start off with.  I could buy a flash recorder like the H2 or the R09, but I already have all of this home recording gear sitting around.  I hate to keep buying more preamps, so I am hoping there is some way to incorporate what I already have.

I have some questions that I have not been able to resolve in my searches here:

*These mics seem to want 9 volts of power; all of my preamps are 48 volt for the condensors needing phantom power.  I am guessing 48 volts would fry these mics, even if I could figure out how to adapt the 1/8" minijack to XLR.  The Mbox and RNP both take a mic level input.  The Mbox also takes a -10 line level input and the RNP takes a +4 line level input.  Am I going to have to break down and buy something like the Church 9100 preamp in order to get these mics to a line level to go into my preamps in the Mbox or RNP?  If I do that, I am going to be adding more stages to the gain stage.

*If I get a flash recorder, it would be so much simpler if I could avoid the battery box/external preamp route and just plug the mic straight into the flash recorder.  The H2 seems to have a noisy preamp AND problems taking a full line level in.  I have looked at the comparisons at Wingfield and Transom, but I still not sure.  I do not need a tuner or 4 tracks of recording or a metronome or any of the other bells and whistles.  I want the cleanest quietest preamp in a flash recorder that also provides enough power for the SP-TFB-2 mics when they are recording a small group of acoustic musicians about 5 feet from the mics at the most.  I would like to spend <$400 if possible.  If a used DAT or Minidisc system would be quieter, then I would be willing to look at that too.  Does anyone have any suggestions?

*Long term possibility - Does anyone have experience with either the T.H.E. BS-3D Binaural Sphere, MBHO's MBNM, Neumann KU100, Jecklin Disk or Schneider Sphere?  These would take a long time for me to save up for and some of them I just couldn't ver justify at all.   There was one other sphere I came across yesterday and now I can't find it.  I think it was about $400 and was a small plastic sphere with small omnis attached.

*One other possibility - If any of you live in Austin, Texas, I would consider paying someone to come record what would amount to a house concert CD recording session.  That way I don't have to teach my wife how to wear the binaurals and not move her head or swallow during a take!!

Any advice anyone can offer would be greatly appreciated and again, if anyone lives in Austin and can do actual Binaural recording, I would pay you to come record.

Thanks,
bilco

[Gutbucket]

The SP-TFB-2's are a good inexpensive way to experiment and learn what works well and what doesn't.  They are a simple back electret capsule that needs 'plug-in power' of around 3-12 volts to operate and will work fine for sources that aren't too loud.  You can use your existing computer interface box but you'll need a 'battery box' that provides 9vdc power between the mics and the input to the interface.  Battery boxes are simple inexpensive things compared to preamps.  You can build one if your so inclined (do a search for how) or buy one with the mics for not much more. Sound Professionals probably sells the mics with one as a package.  Most small flash recorders, old Mini-disks, etc provide plug-in power so you don't need the battery box with them. 

Those mics are designed to go inside your outer ear with the little clear flexible plastic holders, to do true 'binaural recording'.  It's basically two small omnidirectional mic capsules and you can use them anyway you would two omni mics, within the limits of their short hard-wired cable length (meaning you can't separate them by a large distance).  Binaural recordings sound very 'you are there' on headphones, especially if recorded using your own ears.  Headphone playback for other's ears may not match as well.  Most people prefer other mic configurations for playback over speakers.  You can use those mics spaced apart on a stick/dowel/rabbit ear antenna, etc. to make spaced omni recordings (experiment with the spacing), on either side of a jeckin disc (lots of threads here on how to build one) or a sphere (tape them to a dense 'Nerf' or a bowling ball), or make HRTF style recordings which is similar to binaural without the effect of your outer ears.  Many feel HRTF recordings sound almost as as binaural recordings on headphones, but are much better over speakers and more universal for people with different shaped ears than you. The choice depends on what you will do with the recordings considering your target audience and playback system.  You can learn a lot by experimenting with those inexpensive mics that will point you in the direction of future upgrades down the road.

My suggestion is to play around with different mic'ing techniques and make some test recordings to see what works for your scenario and to get the engineering side down pat.  Don't do that with the aim of saving or recording the music.  Once you figure out something that works for you, set up the gear, walk away for awhile to change hats from 'engineer' to 'talent' then come back, hit record, forget about the recording and make some musical magic.

Have fun.

[edited for typo's]

[bilco]

Thanks Gutbucket.  I will order them tonight.  I'll probably get the H2 also, even though it doesn't seem to do to well with external mic or line level input.

bilco

[bilco]

I am going to ask this question again just to make sure......  Is it somehow possible to somehow get these SP-TFB-2 Binaural mics plugged into an external mic preamp that is setup to take XLR mic inputs or +4 line inputs and provides 48 volts of phantom if needed?

I want to record using the true, in ear binaural technique, but I want to use my FMR RNP as the preamp going into my Pro Tools LE setup.

If there is somewhere else I should post this, please let me know.

Thanks again,
bilco

[Gutbucket]

SP-TFB-2 (stereo TRS 3.5mm male output) > (stereo TRS 3.5mm female input) Battery box providing 9v plug in power (stereo TRS 3.5mm female output is typical) > (stereo TRS 3.5mm male input) cable (individual L & R  TS mono 6.3mm male outputs, one L, one R) > (6.3mm unbalanced female input) RNP > however you connect the RNP to your computer interface...

Note:
3.5mm = 1/8"
6.3mm = 1/4"

TRS = tip, ring, sleeve
for stereo, tip = left, ring = right, sleeve = ground

TS = tip, sleeve
tip = signal, sleeve = ground

For the cable italicized above you can make a dedicated cable or use adapters.  If I was to do it with what I normally have in my gig bag, I'd use a 3.5mm stereo TRS to dual male RCA cable and use a female RCA to male 6.3mm TR adapter on each RCA connector, one L and one R. 

Do not use the 48v phantom power on the RNP.  Use the battery box for powering the mics

You could probably also wire an adapter to make an unbalanced connection to the balanced XLR mic input on the RNP, but you'll have to check the manual to see how to wire it correctly as this varies by manufacturer.

Hope that makes sense.

[bilco]

Thanks again for the reply.  I am not sure the RNP would know what to do with the 1/4" input.  It has a Neutrik input, which gets interpreted as an instrument input, like from my bass.

I did find this mic -  Sennheiser MKE-2-PC - kind of pricy, but it does have the battery box and an XLR connector for plugging into the preamp.

Maybe I am making this harder than I ought to.  I guess I could just surrender to getting a used Dat recorder or a flash recorder, although all of the flash recorders seem to have at least one shortcoming.

I need to do more reading I guess.......

Thanks again for taking the time to write the detailed response,
bilco

[Gutbucket]

The instrument input will work fine.  That's an unbalanced input and what you want.

I thought the RNP had 1/4" unbalanced inputs on the front and XLR's inputs on the back (along with insert points and the outputs) but I must be mistaken.  A 'combo' Neutrik 1/4" & XLR input jack will work the same way though.

[ambo]

SP, Microphone Madness and others offer a stereo miniplug to dual XLR transformers, which will allow minimics to be powered by 48v phantom. The transformers drop the voltage to 9v or less, allowing most minimics to be powered by preamps like RNP. Microphone Madness quoted me $60 for this cable. there may be noise issues though, with all of the balanced/unbalanced business going on. It may be easier to just get a mini recorder if stereo recording is what you're after. I use an R09 with and without various preamps. If the R09 preamp noise is an issue, then the mini mics are going to be far more of an issue, because they are very noisy for quiet sources. Most tiny capsule mics are on the noisy side.

[bilco]

I thought the RNP had 1/4" unbalanced inputs on the front and XLR's inputs on the back (along with insert points and the outputs) but I must be mistaken.  A 'combo' Neutrik 1/4" & XLR input jack will work the same way though.

You are right, I must have really been tired when I wrote that.  The Mbox has Neutrik, but the RNP is just exactly like you pointed out. 

I just won a pair of the SP-TFB-2 Binaural mics from The Sound Professionals, Inc. !!!!

Way cool, I can't wait to start experimenting and recording our band straight to 2 track with Binaural or HRTF technique.  Every sound clip I have heard of either of those 2 methods just blows away everything I have done with PT LE and overdubbing the instruments a track at a time.  It also sounds way better than the X/Y recordings I have done with my pair of SM81s.

I have spent 3 nights in a row now, googling and devouring every thread I can find about Binaural and HRTF recording.  Let's see what I can find tonight.......

Thanks again,
bilco

[bilco]

SP, Microphone Madness and others offer a stereo miniplug to dual XLR transformers, which will allow minimics to be powered by 48v phantom. The transformers drop the voltage to 9v or less, allowing most minimics to be powered by preamps like RNP. Microphone Madness quoted me $60 for this cable. there may be noise issues though, with all of the balanced/unbalanced business going on. It may be easier to just get a mini recorder if stereo recording is what you're after. I use an R09 with and without various preamps. If the R09 preamp noise is an issue, then the mini mics are going to be far more of an issue, because they are very noisy for quiet sources. Most tiny capsule mics are on the noisy side.

Thanks for the tip.  I will give them a call and talk about the potential noise.  $60 is not bad if it works well and go straight into my RNP. 

I can not believe I have been going to home recording threads and even PSW and 3dB for years and I am just now finding out about Binaural and HRTF.

Thanks again,
bilco