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Gear / Technical Help => Battery Boxes, Preamps, Mixers, ADCs, and Processors => Topic started by: djphrayz on April 02, 2012, 10:33:54 PM

Title: ca 9100 interface
Post by: djphrayz on April 02, 2012, 10:33:54 PM
I'm a newbie, and I'm putting together my first rig on a budget.  Here's the rig I'm considering:

CA-14 Cards/Omni/9100 Preamp
Tascam DR-40

I've listened to some pulls with the CA-14s and like what I hear, but I have a few questions about the 9100s interface.  I am looking at the Tascam DR-40, which has a pair of combo XLR - 1/4" TRS balanced inputs but no 1/8" input.  BTW, I took a look at the Sony PCM-M10, but I want to have the flexibility of using standard phantom powered XLRs for other applications.

I am curious if I will be able to get a clean interface from the 1/8" unbalanced 9100 preamp output to the balanced 1/4" inputs to the recorder?  If so, would I just need a Y-adapter with a single 1/8" stereo TRS to 2 unbalanced 1/4" TS plugs?  I am thinking that the 1/4" might be a bit tighter / lower profile with a 90° plug rather than the XLRs.

Any suggestions?  Thanks in advance.

-Rick
Title: Re: ca 9100 interface
Post by: TimeBandit on April 03, 2012, 02:43:45 AM
Way one ask Church to build you a preamp with these connectors so you don't have to use adaptors (not a friend of adaptors they usually get loose on a recording....)

Title: Re: ca 9100 interface
Post by: Walstib62 on April 03, 2012, 09:25:10 AM
Way one ask Church to build you a preamp with these connectors so you don't have to use adaptors (not a friend of adaptors they usually get loose on a recording....)

I don't think a new preamp is necessary at all. A 1/8" TRS to 2-1/4" TS plugs would work fine. Right angle is up to ya.

Title: Re: ca 9100 interface
Post by: djphrayz on April 03, 2012, 09:41:52 AM
I don't think a new preamp is necessary at all. A 1/8" TRS to 2-1/4" TS plugs would work fine. Right angle is up to ya.

I just wasn't sure about unbalanced to balanced connections. Thank you Walstib62! :D
Title: Re: ca 9100 interface
Post by: Walstib62 on April 03, 2012, 10:24:11 AM
I don't think a new preamp is necessary at all. A 1/8" TRS to 2-1/4" TS plugs would work fine. Right angle is up to ya.

I just wasn't sure about unbalanced to balanced connections. Thank you Walstib62! :D

Your 9100 is unbalanced. If you plug male TS plugs into the DR-40, the input signal will be unbalanced. Balanced signals  will always have 3 wires (pins) on both ends of the cable for each channel.
Title: Re: ca 9100 interface
Post by: Jonmac on April 03, 2012, 12:04:57 PM
I run line in from a mixer, into the DR-40, with unbalanced TS plugs, without a problem.

Remember though, that the DR-40 requires +4db professional levels to get a 0db recording level, not -10db like some portable recorders. I don't know what the 9100 pre-amp produces.
Title: Re: ca 9100 interface
Post by: djphrayz on April 03, 2012, 12:39:13 PM
Your 9100 is unbalanced. If you plug male TS plugs into the DR-40, the input signal will be unbalanced. Balanced signals  will always have 3 wires (pins) on both ends of the cable for each channel.

Right.  I meant unbalanced jack to balanced jack with unbalanced cable.  I was concerned about grounding the signal carrying (-) conductor at both ends.  Is it better to use a special 1/4" TRS connector with a lifted ground contact, which will allow the signal to only be grounded at the unbalanced source?  But since this cable will only be about 1 to 1-1/2 feet long, perhaps this would be ground-loop avoidance overkill?

I run line in from a mixer, into the DR-40, with unbalanced TS plugs, without a problem.

Remember though, that the DR-40 requires +4db professional levels to get a 0db recording level, not -10db like some portable recorders. I don't know what the 9100 pre-amp produces.

Jonmac, from the documentation, I see that when the EXT IN switch is in the LINE position, the input is spec'd at +4 dBu nominal to +20 dBu max.  When the EXT IN switch is set to MIC, the nominal input level is -19dBV (-16.78 dBu) and max input level is -3 dBV (-0.78 dBu)*.  I notice a gap from the -0.78 dBu to +4 dBu from max Mic In to nominal Line In.  Can this be a problem if the SPL of the event are desire this "dead spot" for optimum record levels, or is does overlap exist where no "Minimum" level is spec'd?

Can anyone tell me for certain that the CA-14 <-> 9100 combo will be fully compatible with the Tascam DR-40?

*note that converted values for apples to apples comparison came from an online calculator and may need to be verified.  (Why would they use different units in this sort of spec?!?!)
Title: Re: ca 9100 interface
Post by: djphrayz on April 04, 2012, 10:07:23 AM
major revision above.. not sure if this conforms to board etiquette, but hey... I'm a n00b, forgive me!
Title: Re: ca 9100 interface
Post by: Walstib62 on April 04, 2012, 11:12:59 AM
Get the 1/8" stereo to dual 1/4" TS cable. Run out of the CA pre to line in on the Tascam. It will work fine.  You will have to play arond with the settings, but you should be fine.
Title: Re: ca 9100 interface
Post by: Jonmac on April 04, 2012, 11:24:40 AM

[/quote]

Jonmac, from the documentation, I see that when the EXT IN switch is in the LINE position, the input is spec'd at +4 dBu nominal to +20 dBu max.  When the EXT IN switch is set to MIC, the nominal input level is -19dBV (-16.78 dBu) and max input level is -3 dBV (-0.78 dBu)*.  I notice a gap from the -0.78 dBu to +4 dBu from max Mic In to nominal Line In.  Can this be a problem if the SPL of the event are desire this "dead spot" for optimum record levels, or is does overlap exist where no "Minimum" level is spec'd?

Can anyone tell me for certain that the CA-14 <-> 9100 combo will be fully compatible with the Tascam DR-40?

*note that converted values for apples to apples comparison came from an online calculator and may need to be verified.  (Why would they use different units in this sort of spec?!?!)
[/quote]

I wouldn't recommend using the mic in setting with a pre-amp, the level will be much too high.

Don't worry if you can't achieve 0db when recording, around -12 on the meter is fine, the line in noise level is so low, you will be able to normalise to near 0db in post, without any noticeable increase in noise.

,
Title: Re: ca 9100 interface
Post by: djphrayz on April 04, 2012, 02:00:29 PM
Thanks a lot fellas.  I tend to over analyze things, especially before a purchase like this.  Hate to be trying to sell gear because I made a misinformed / poorly researched purchasing decision. 

This is off topic for this thread, but since you're here, I am wondering if I could find comparable or better quality out of an off the shelf pair of SDC or LDC mics for under $400?

Thanks again for sharing your knowledge!

-rik
Title: Re: ca 9100 interface
Post by: bryonsos on April 04, 2012, 02:16:31 PM
Thanks a lot fellas.  I tend to over analyze things, especially before a purchase like this.  Hate to be trying to sell gear because I made a misinformed / poorly researched purchasing decision. 

This is off topic for this thread, but since you're here, I am wondering if I could find comparable or better quality out of an off the shelf pair of SDC or LDC mics for under $400?

Thanks again for sharing your knowledge!

-rik

http://taperssection.com/index.php?topic=152459.0

The Audix in particular are great mics.
Title: Re: ca 9100 interface
Post by: djphrayz on April 04, 2012, 04:10:22 PM
links to any recordings?  From what I've picked up so far, seems my best all-around bet if I choose 1 set of mics would be cards.  Is that right?  I will be taping five phish shows this year from OTS, and I want to make sure that the bass isn't puny.  Of course I want decent sounds throughout the freq. range, though I know at this price point I will be compromising clarity and detail.  I listened to a Bela Fleck and the FT show pulled with the CA-14s, and they sounded decent to me.  I would just prefer something a little more off the shelf with not such a long lead time, ya dig?

Perhaps I should post a new thread in the mics section?  Help a newb out!

peace

-rik
Title: Re: ca 9100 interface
Post by: bryonsos on April 04, 2012, 04:28:51 PM
You can get card (maybe omni too) caps for the Audix, plus there are cables to run them as actives. You should be able to find scores of examples on LMA. Really nice mics, killer price and no worries dealing with paulbaptist. I bought the B3s in that listing and some 460s from him.

Edit, the Audix will need P48, but you should be able to run the ATs with a 9100. Those are real nice too.
Title: Re: ca 9100 interface
Post by: Fried Chicken Boy on April 04, 2012, 04:55:53 PM
http://taperssection.com/index.php?topic=152459.0

The Audix in particular are great mics.

Also a pair of minty (according to the post) Audio-Technica AT4031's in that same listing for a nice price.  One of the most underrated manufacturers around.  Unlike the Audix, however, they are cardioid only.  Having the changeable caps is a nice feature if you feel like picking up other patterns.
Title: Re: ca 9100 interface
Post by: paulbaptiste on April 05, 2012, 12:11:14 AM
You can get card (maybe omni too) caps for the Audix, plus there are cables to run them as actives. You should be able to find scores of examples on LMA. Really nice mics, killer price and no worries dealing with paulbaptist. I bought the B3s in that listing and some 460s from him.

Edit, the Audix will need P48, but you should be able to run the ATs with a 9100. Those are real nice too.
You can run them off battery power with the cables church make also.  A great feature having the option of p48 or battery power.  They have omni caps, card, and supercard(shotguns).  very versatile set of mics that make stellar recordings.
Title: Re: ca 9100 interface
Post by: djphrayz on April 06, 2012, 07:53:56 PM

Also a pair of minty (according to the post) Audio-Technica AT4031's in that same listing for a nice price.  One of the most underrated manufacturers around.


I feel really good about purchasing these today!  Thanks for the tip!