Syntrillium Backup Forums :: View topic - Recording telephone interviews with Cool Edit 200

Chris tallentire · Posts: 4

I would like to record interviews done over the phone, at my home. There are three elements to this:

1. I need to have my voice recording through a microphone;
2. My guest's voice has to be recorded from the phone line and into the sound card; and
3. My guest and I have to be able to hear one another.

Does anyone have any ideas on how I can achieve the above?

I know there's a simple way of wiring a telephone to the sound card, but phone companies don't like this and also my voice is input through the telephone, so it isn't broadcast quality.

Maybe there'a a clever way of using a modem for this.

Thanks to Syntrillium for a fantastic product in Cool Edit 2000, and I love the 4 track plug in. Sorry if this subject isn't really a Cool Edit issue.

Best wishes
Chris Tallentire
Environmental Reporter and Investigator

Edited by - Chris tallentire on 04/07/2001 02:19:32 AM

Dave Merkel · Posts: 29

Hi Chris:

I'll give you my feedback on the best way of doing this, albeit not a cheap method. I'd look forward to hearing from anyone else that has achieved the same results with different techniques (if possible).

The only technique I'm familiar with, that I use in my own studio, is by using a "telephone interface" (they're often referred to as a "telephone hybrid" as well). No matter what they call them, they all take the "two wire" telephone audio and convert it to "four wire" ... two wires for the caller on the phone (referred to as Receive audio), and two wires for the microphone/studio audio (referred to as Transmit audio). How each unit technically achieves that result varies greatly between each unit, thereby producing a wide variety of results.

While the older analog units are still available, you'll achieve the best results from the new digital hybrids. In my opinion, the key difference to look for when shopping for one is each unit's ability in what's called the Null circuitry. It is the Null that effectively seperates your audio from the callers audio, giving you control over each seperately on a mixer with the least amount of bleed-through.

Another feature of a telephone hybrid/interface is that most meet technical specs of local phone companies for POTS lines ... providing the correct impedence, loading, etc on the phone line(s).

The only drawback of using a hybrid/interface is that you must have a mixer that supports mix/minus ... it will prevent you from sending the "callers" audio back down the phone line, which would cause nothing but feedback. You can achieve the mix/minus with any of the Mackie mixers, to name just one of many. It's simply a matter of being able to send the audio from any given channels on your mixer to different sources.

If you choose to purchase a phone hybrid, shop carefully. Like most studio equipment, the less money you spend means the less quality you get. But you can always find the right balance.

Anyone else here have any others ideas to separate mic audio from phone line caller audio?

Good luck Chris -
Dave

Chris tallentire · Posts: 4

Hi Dave
Many thanks for your response and comments. I'm having great fun checking out all the telephone hybrid/interface possibilities.

I live an hour from my radio studio, so being able to do home phone interviews will save me so much time. Living in Australia I'll be able to stumble out of bed and do interviews with USA guests at a time that suits them! An absolute bonus!

Thanks again Dave -
Chris

Edited by - Chris tallentire on 04/07/2001 10:58:52 PM

roverradio · Posts: 14

Chris:

I've been using a rather old Gentner G2500 hybrid for years. It's an analog box (not nearly as fancy as the digital ones), but it does exactly what you need.

For a cheap method, put a mic next to a speakerphone. Then record into CoolEdit. If you run some processing on it and tweak the settings, you'd be surprised how good the quality can turn out (Dynamics Processing/Voice Compressor). I've had to do this a couple of times in a bind and it worked OK.

Rover

Jay Marble · Posts: 145

Phone Interviews:

I have not yet aquired a good phone hybrid..but I have come
up with 2 interesting ways of recording phone interviews.

If I am just going for actualities, I plug a phone line
into the in-put jack of a Marantz tape deck. I run a patch
from the Marantz's rca output to the input of my mini-disk.
Put the marantz in source mode and pause/record. Pretty
good quality, mostly because there is no tape hiss from a
marantz in source mode.

If I intend to air the interview as an interview, I do
something similar, but using my computer instead of the
mini-disk.

Instead of using the marantz's rca output, I use the
headphone jack. I run a patch from the headphone jact to
the breakout box of my Darla soundcard. Then I bring up a
stereo waveform on my cool edit. I record my voice using
my studio mic on one track. The phone feed is recorded on
the other track. Once the interview is over I silence my
voice on the phone feed track....the result is a faily
clean interview.At least my voice is recorded with good
quality..Even after I get a good phone hybrid, I will
likely continue to use a variation of this method..

djlyon · Location: Romania Posts: 369

This is how i've done it:
I used a modem, and connected the modem's speakerOut to the soundcard's lineIn jack, using a 3" jack-jack cable.
Then i open some kind of terminal window, type ATH1 to tell the modem to pick up the receiver, and from another phone i dial the number. Then i run CEP and rec through lineIn using the soundcard. When i the interview is over, i type ATH in the terminal window, and voila!
The advantage is that there's no air-connection (like microphone to handset), everything is done analogically and digitally, so no noise can enter my source. A very HQ recording.
Disadvantage: a little bit complicated.

PS: i used to have a modem on the radio production PC Smile