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Phone Hybrid

Hey guys...I am at the stage in my home VO studio where I need a telephone hybrid. Keep in mind I'm on a tight budget and I know that doesn't help much, but what can I say? I was curious if maybe anyone out there was selling some used phone equipment? I found on e-bay a surplus place that has about 7 or so used Telos Delta 100 Digital Hyrbids. Does anyone know about these? That me be what I end up getting, but wanted to check with my fellow broadcasters! Thanks guys.
 
You certainly can't go wrong with a Delta 100 if it is within you budget. This was Telos' top-of-the-line standalone hybrid until they stopped making them due to discontinued parts. These are very reliable so I wouldn't worry too much about the parts issue

Their Telos ONE is another good hybrid and would be less expensive.

Rolf Taylor
(Former Telos Employee)
 
The 100 is a good unit, but ask the seller how old the unit is and if it still has the original power supply. The power supplies on these tend to cause problems as they age and are easily updated.
 
The Telos 100 is a great box, but probably more than you need.

Let's review what a phone hybrid does. The telephone line is a single circuit, with both send and receive audio on it. The "send" audio is from your board in the studio. the "receive" audio is the caller, wherever he may be. The hybrid seperates those into two circuits, one for send, the other for receive.

The receive audio, ideally, would be ONLY the receive audio. Even though it came from a circuit that contained both send and receive, the send audio is "nulled" out, so that theoretically only the receive audio is left.

The null circuit works by balancing the audio in one place against the audio in another place. When they match perfectly, you get a perfect null. But the reality is that they never match perfectly, so the null isn't perfect, and you end up with a little bit of your send audio on the receive audio pot on the board.

When this is really bad, your mic seems to be hotter through the caller pot than the caller himself is. The function of this hybid is the main reason you constantly hear talk show hosts telling their caller to speak up. Because even the best phone hybrids can only do so much.

The biggest problem in obtaining a consistent null in a radio station is that the phone lines are part of the null circuit, and the impedance of each phone line differs from the next. While a good sounding hybrid can be built really cheaply, it has to be adjusted for the deepest null on one phone line only. The other lines may not sound so good!

Thus, the "auto nulling" phone hybrids were invented, of which the Telos 100 is one of the best ones ever made. When you pick up the line, the hybrid gives a burst of noise down the phone line and an onboard computer nulls out the hybrid to that line. It all happens in less than a second, and you get the best null on that line that you can get.

But if you only have 1 phone line, that box may be overkill. Yes, it has some built in compression and EQ. But really... the big thing you are paying for with that is the auto null feature.


If money were an issue, I would look for an old Gentner SPH 3, 4, or 5 on Ebay. Or I'd consider the Broadcast Tools TT1 for $129. http://www.bswusa.com/proditem.asp?item=TT1

Or a step up from that is the JK Audio Inline Patch for $239... http://www.bswusa.com/proditem.asp?item=INLINEPATCH

Keep in mind you will have to manually null those units to your phone line. It's a matter of sending a tone down the line and adjusting a pot for minimum bleed-through.

But it beats spending a lot of money you don't need to spend.
 
You guys ROCK! Thank you SO much for the advice so far. Below is a link to the Telos Delta 100 Hybrid on Ebay I found.

My big thing, and as said above, it isn't TOTALLY possible to get great separation, I just want caller audio coming in on my mixer and they hear me. The hybrid basic, if you will.

I was looking at the JK Audio Broadcast Host but the biggest problem I have come across reading about that is a hum issue. And for the price, it sounds like I could get the Delta 100 which sounds like an overall better unit.

Here is another issue hitting me...let's say I get the Delta 100, all is good then out of the blue, something happens. What are my repair options? Would Telos be able to do anything? I just don't want to be stuck up the stream without a paddle, if you catch my drift.

I also found a guy selling a Telos ONE which I would love to get, I don't think I will get it due it being a bid only and my budget. Hence where you guys come in!

http://cgi.ebay.com/The-Telos-100-D...QQssPageNameZRSS:B:SRCH:US:101#ht_4194wt_1165
 
The reason you need good separation is not because it makes it hard to mix, but that once the caller audio is mixed in with your mic audio the mic audio will sound "funny" (tin-ee, hollow, etc).

A passive hybrid will not be able to account for the fact that every phone call is different and the hybrid has to deal with the situation end-to-end. You want to avoid a phone "coupler" which is designed for one-way audio and therefore need not worry about cancellation.

Lots of good materials on the Telos web site in case you are curious.

One other thing to consider. If you will be buying an ISDN codec, some of these can work in a pinch as hybrids. Ironically they are not as sophisticated as an adaptive hybrid, but they may do well enough.

Rolf Taylor
 
For stations using digital phone systems, sometimes the economical option is a hybrid that works using the handset portion of the phone. Gentner used to have a product for this, but no more. JK Audio has one, and it isn't bad.
 
See and I would totally go with a JK Audio Digital Hybrid...the Broadcast Host I believe. My only deal is I read a lot about a hum issue. Right now I have a Behringer mixer that I would be using. It's a nice mixer as far as it doing what I need it to do. No hum or hiss....I just want good clean caller audio for a nice crosstalk, which again brings me to the Telos Delta! LoL.

I read earlier that the power supply is the most common issue. They should still be able to replace that regardless of the parts still being manufactured, right? I would imagine it would be similar if not the same as the Telos 1X6?
 
The power supplies are now provided by an outside vendor. You can get them from Telos or direct. They're easy to swap out. Each Telos product requires a different supply. Get the right one. Make sure the 5 volt rail is running 5.1. Anything you send back to Telos comes back ready to go.
 
OK cool...so overall you think it's a good buy? How much would Telos charge to put in a new power supply? or is it easy for say, someone like me to do it?
 
Eight screws on the top, four in the supply shield. Unplug the two connectors and pull the old one out. Reconnect the new one just like you took the old one out. Check the 5 volt rail for 5.1 volts and button up. Be sure you know how to use a volt meter and don't get across the input AC. There's one pot on the board that adjusts the 5 volt rail. There's only one and that's all it does.
 
OK, sounds pretty simple...but again, that is worst case that the power supply goes out. Or do you recommend replacing it anyway? I just don't want to spend the cash on a unit that may not work for a while!
 
You need to talk to whomever has it for sale and see what kind of answers and vibe you get. It may be in perfect shape and it may need some attention. Ask for it to be tested. Maybe you could even call in on it and see how it performs. The link you posted to the 100 looks pretty good. These one box units are pretty reliable.
 
$305 would be a good deal on a used Telos One. I would grab this because it is a real steal - If I recall correctly this used to go for $1800 list price!
 
I just bought one! I will keep everyone posted on how it turns out. I think a good decision swayer was that i learned from Telos that they still repair the units SO that is a peace of mind...just not fond of the hourly rate!
 
Just wanted to mention that I have installed several Gentner or ClearOne AP10 digital hybrid units in the past. Usually if you luck out you can find these on Ebay for very low $$. It's a single rack unit, the only thing funky is the audio connector is not an XLR but one of those 3 pin horizontal connectors that some audio distribution amps might use. Other than that they usually work fine and work just by pushing one button to connect. They also have a remote function whereby you can remote the on/off functions via a D connector on the back. Do a search on AP10 and you'll find specs, pics, etc.

Here's a pdf file with pics & details on it: http://www.workingbouvier.com/802-150-201-Rev2.0_AP10DS.pdf
 
ontheair247 said:
Just wanted to mention that I have installed several Gentner or ClearOne AP10 digital hybrid units in the past. Usually if you luck out you can find these on Ebay for very low $$. It's a single rack unit, the only thing funky is the audio connector is not an XLR but one of those 3 pin horizontal connectors that some audio distribution amps might use. Other than that they usually work fine and work just by pushing one button to connect. They also have a remote function whereby you can remote the on/off functions via a D connector on the back. Do a search on AP10 and you'll find specs, pics, etc.

Here's a pdf file with pics & details on it: http://www.workingbouvier.com/802-150-201-Rev2.0_AP10DS.pdf

I SO almost bought one but the connectors put me off! I wasn't sure if that "worked" like a hybrid because I know since Clear One bought or acquired Gentner, I wasn't sure how much they modified their stuff. Do they make connectors that can lead to XLR or TRS?
 
You can either use these connectors directly or make an adapter yourself or even install XLR connectors chassis mounted if you feel like modifying it. The connectors are similar to th eones used on audio distribution amps with the 3 terminal push on with screws that compress the wires.

And yes it does work as a hybrid.
 
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