DB25 "audio" cables verses db25 serial port cable

[Audionaut]

Hey guys,
Is there any really big difference between DB25 cables made for high end audio and "better" DB25 serial port cables. I'm putting together a control room with Switchcraft 9625 patchbays that have 12 DB25 connectors in the back. I went with these PBs since the Dangerous music monitor ST and SPL Mix Dream summing bus that I'm installing have DB25 I/Os in back.
Now for the good part:
My buddy in NYC is currently running the same setup and saved a bundle by interfacing everything with what he referred to as "off the shelf printer cables" from radio shack.
I'm assuming that there may be issues with shielding or RF over distance and maybe different impedance ratings etc. But need these cables 6' or shorter.
The cash breakdown is as follows:

6' Tripp Lite or Belden Gold plated DB25 M/M Line through cables: $2.40 EACH
Digidesign "digisnake" DB25 - DB25 $150.00 EACH
1.5meter Monster Cable DB25 to db 25 $199.95 EACH

I need about 14 snakes to interface all of my gear, so do I spend $50 on the cheap stuff or nearly $2800.00 on the good stuff? Is there a difference and is it worth it?
Thanks for your input.

[themaidsroom]

i think there are at least a few other options in between....get a quote from redco
for the shortest cables that will have adequete service loop....



be well


- jack

[Audionaut]

Thanks. I've seen lots of cables priced between $3 and $250, that's exactly why I'm posting on Geekslutz. I'm looking for a geekier answer. Anyone ever A/B'd DB25's or seen any REAL specs that go beyond "...but this is Monster Cable" or "this was made for pro audio." I already know what the sales guy at Guitar center would say... who really knows their cables?

[vince @ speck]

Originally Posted by Audionaut

Hey guys,
Is there any really big difference between DB25 cables made for high end audio and "better" DB25 serial port cables. I'm putting together a control room with Switchcraft 9625 patchbays that have 12 DB25 connectors in the back. I went with these PBs since the Dangerous music monitor ST and SPL Mix Dream summing bus that I'm installing have DB25 I/Os in back.
Now for the good part:
My buddy in NYC is currently running the same setup and saved a bundle by interfacing everything with what he referred to as "off the shelf printer cables" from radio shack.
I'm assuming that there may be issues with shielding or RF over distance and maybe different impedance ratings etc. But need these cables 6' or shorter.
The cash breakdown is as follows:

6' Tripp Lite or Belden Gold plated DB25 M/M Line through cables: $2.40 EACH
Digidesign "digisnake" DB25 - DB25 $150.00 EACH
1.5meter Monster Cable DB25 to db 25 $199.95 EACH

I need about 14 snakes to interface all of my gear, so do I spend $50 on the cheap stuff or nearly $2800.00 on the good stuff? Is there a difference and is it worth it?
Thanks for your input.

An off-the-shelf DB25 "serial cable" is nothing more than 25 unshielded wires bundled together. Unsuitable for professional audio interface.

The DB25 "audio cable" has (8) 3-conductor shielded cables suitable for audio interface. Many DB25 audio cables now use 110ohm AES/EBU cable.

Is your friend really using printer cables for audio interface?

[tINY]

For short runs in a controlled environment, you might get away with the printer cables. Your cross-talk will be higher.

For that many connections, it'd be worth buying a crimping tool, connectors and bulk 8-pair snake cable.



-tINY

[Audionaut]

YEah, it looks like we're going to do exactly that, get a bunch or 8channel mogami and crimp on our own DB25's. I still have to pick up at least one cheap serial cable to compare!!!
thumbsup

[tINY]

I don't know what format all these DB25 connectors are, but do yourself a favor and just get the 110Ω low capacitance cable and be ready for digital. It works fine for analog signals too.




-tINY

[Jon Kraft]

I would make your own cables. In fact, I did the same thing. Gepco makes nice 110ohm snake cable. It is VERY nice to work with.

26 gauge is crucial. Those DB25 are pretty tight. I actually soldered mine, though. The crimp option sounds nice.

Jon

[jacko]

I just investigated £60 worth DB25-DB25 audio cable from Direct Cable Systems. Surprisingly it is a bunch of wires with one common shield. DB25-XLR has shielded pair, but this obviously makes sense, as XLR endings have to be separetly shielded.

The DB25-DB25 is based on 7-2-25C cable worth £1 per 1 meter and metal DB25 connectors worth probably another £4.

Check this one out:
Amazon.co.uk: Belkin Pro Series IEEE 1284 Parallel Switchbox DB25 Male to Male Cable 1.8m: Electronics & Photo: BELKIN

It has separetly shielded pairs and it is £3 only...

[David Kulka]

Originally Posted by tINY

I don't know what format all these DB25 connectors are, but do yourself a favor and just get the 110Ω low capacitance cable and be ready for digital. It works fine for analog signals too.

-tINY

But be aware that digital DB25 cables use a different pinout, so to use you'd need to rewire both ends of your snakes to use them for digital signals.

[jacko]

Originally Posted by David Kulka

But be aware that digital DB25 cables use a different pinout, so to use you'd need to rewire both ends of your snakes to use them for digital signals.

I thought Pro Tools uses TDIF standard for analogue connections? Doesn't it?

[Matt Syson]

Hi
Twisted 'correct' pairs with an overal screen would be fine from say PT outputs and anything with balanced outs. There are BBC studios wired with miles of this stuff (for line level signals) so it can't be too bad. For short runs you hardly need the twisted pairs but it will help slightly.
Copper thickness in the 'super cheap' printer cables can be very thin so go for better grades.
Matt S

[David Kulka]

Originally Posted by jacko

I thought Pro Tools uses TDIF standard for analogue connections? Doesn't it?

Confusion reigns! 110 ohm digital (AES) cable had been mentioned, and I was saying that digital DB25 cables use a different pinout than analog DB25.

TDIF, the Tascam digital interface, is a third connector standard that is not compatible with standard analog or AES digital DB25 cables.

[MsM]

Originally Posted by Matt Syson

Hi
Twisted 'correct' pairs with an overal screen would be fine from say PT outputs and anything with balanced outs. There are BBC studios wired with miles of this stuff (for line level signals) so it can't be too bad. For short runs you hardly need the twisted pairs but it will help slightly.
Copper thickness in the 'super cheap' printer cables can be very thin so go for better grades.
Matt S

I've been wondering if it might make sense to 'standardize' on Cat5E FTP (foil shielded) cable for general fixed installation line level audio usage (4 pairs), and for AES/EBU digital. Runs would be less than 50m. Seems to be fairly reasonably priced vs. audio multichannel, but I've been curious about crosstalk for audio. I guess the above quote would apply for this kind of cable too?

[Matt Syson]

Hi
I would suggest at least trying some Cat5 or 6 shielded. The original post was about 25Dsubs so 4 pairs is not enough (to look sensible) but for other runs, balanced, at a similar level should be fine, just don't tell anyone otherwise those who have forked out serious money for 'fancy' cable will be well miffed.
The twists on Cat cable are there to reduce crosstalk between send / receive channels and will do the same for audio. If you look I believe the twist rate is different between pairs.
Give it a go, and if it fails it was cheap and you can tie up the plants in the garden or whatever when you pull it out.
You could almost think as 'future proof' in that eventually when everything has network connections your cables will already be there.
Matt S

[Firechild]

Waking up an old thread...

I will connect a Digidesign Control 24 with 192 I/O with DB25 in both ends.
Is there a proof to not use very cheap printer cables?
I need a 7.5 meter long cable.

[Matt Syson]

Hi
No one seems to have commented one way or the other since the thread was 'alive'.
For the length you say I would at least try it as long as both ends are 'balanced' (in and out).
If you can perceive any crosstalk, which would most likely be at 20KHz you can then decide if it was worth the punt.
Matt S

[Firechild]

Ok, I skipped the idea with printer cables.

I used another trick...it works, the sound is coming through anyway...

I had two snakes left with DB25 to AES/EBU.
I just connected the XLR´s together and from two cables I have now one cable with DB25 in both ends...

The only downside was that the routing was twisted but it is easily fixed in pT I/O meny.

Output 1-2 from Control24 comes into 5-6 into 192.
3-4 to 7-8
5-6 to 1-2
7-8 to 3-4.

Will there be issues with the sound quality using AES/EBU cables for +4 balanced analog audio?

[Matt Syson]

Hi
No!
You could use 8 pieces of 2 core 'bell wire' (with a few twists in it) across the floor and if it is balanced at both ends you probably wouldn't notice any problems.
Matt S

[krikorola]

Hello, i have a similar question.
I want to separate one of the Dsub output of my SSL alpha link into two Dsub with a Y cable. I could make the cable, but it is a painfull work and i found that DB25 'Y' Cable - 1 Male to 2 Females 18in
Do you think this can work? the wire is straight, i don't know if it is shielded though.
the idea is to use on to go into my summing amp and one into a patch, this way i can use it for different project, including outboard effects or no.
thks

[Matt Syson]

Hi
That should be fine but check the male / female status of the connectors depending on exactly what you are trying to achieve. As the signals are 'line level' and low impedance there should be no problems even if they were not shielded.
Strictly speaking the wires will not be twisted into the 'pairs' used by the Tascam pinout but again it is only short so will not cause a problem.
Matt S

[krikorola]

Originally Posted by Matt Syson

Hi
That should be fine but check the male / female status of the connectors depending on exactly what you are trying to achieve. As the signals are 'line level' and low impedance there should be no problems even if they were not shielded.
Strictly speaking the wires will not be twisted into the 'pairs' used by the Tascam pinout but again it is only short so will not cause a problem.
Matt S

thanks i'm gonna go for it!

[krikorola]

Originally Posted by Matt Syson

Hi
That should be fine but check the male / female status of the connectors depending on exactly what you are trying to achieve. As the signals are 'line level' and low impedance there should be no problems even if they were not shielded.
Strictly speaking the wires will not be twisted into the 'pairs' used by the Tascam pinout but again it is only short so will not cause a problem.
Matt S

The company told me they are going to modify my order, make it 6inch long, and pair opposite wires. So it is all good!

[Matt Syson]

Hi
The other REAL cheap way of doing what you want with paralled outputs is to get a couple of feet of ribbon cable (25 way of course) and suitable 'IDC' DB25 connectors which you carefully 'crimp' onto the cable. The audio pairs stay together as they should do but it is not 'twisted' so in extreme situations COULD pick up interference but for line level we would have to talking really extreme to give any problem at all. Much of the gear you buy will have this kind of setup on the inside as this is the reason this connector is popular for multichannel audio.
This sort of wire assembly is not terribly strong physically but you could be inventive with assorted hardware.
Matt S

[peeej1978]

Originally Posted by Matt Syson

Hi
The other REAL cheap way of doing what you want with paralled outputs is to get a couple of feet of ribbon cable (25 way of course) and suitable 'IDC' DB25 connectors which you carefully 'crimp' onto the cable. The audio pairs stay together as they should do but it is not 'twisted' so in extreme situations COULD pick up interference but for line level we would have to talking really extreme to give any problem at all. Much of the gear you buy will have this kind of setup on the inside as this is the reason this connector is popular for multichannel audio.
This sort of wire assembly is not terribly strong physically but you could be inventive with assorted hardware.
Matt S

Hi Matt,

I'm looking at the possibility of doing just that to connect an 8 channel mic pre to one of the 8 channel inputs on my 24 track HDD recorder. Presumably the above method only works if the PinOut of each DB25 socket is identical? Failing this, the only option would be to solder = correct? Excuse my ignorance - I've never made my own cabling.

[Bill@WelcomeHome]

Originally Posted by Matt Syson

Hi
The other REAL cheap way of doing what you want with paralled outputs is to get a couple of feet of ribbon cable (25 way of course) and suitable 'IDC' DB25 connectors which you carefully 'crimp' onto the cable. ....

back when the first DA88s came out we got three of them (which ended up being a bit different than the final shipping versions and eventually had to be replaced). We needed custom cabling for the racks and Tascam was not interested in sharing the pinout. George Petersen from Mix got it sussed out and we used ribbon cables and crimp through connectors to make our connections. Worked just fine inside of our steel racks. When he printed an article describing the pinouts, Tascam was a little miffed. Anyway, it worked with the digital signal from DA-88s.

[peeej1978]

Originally Posted by Bill@WelcomeHome

back when the first DA88s came out we got three of them (which ended up being a bit different than the final shipping versions and eventually had to be replaced). We needed custom cabling for the racks and Tascam was not interested in sharing the pinout. George Petersen from Mix got it sussed out and we used ribbon cables and crimp through connectors to make our connections. Worked just fine inside of our steel racks. When he printed an article describing the pinouts, Tascam was a little miffed. Anyway, it worked with the digital signal from DA-88s.

Presumably you were connecting like for like pinouts though? My concern is I'm connecting two different pieces of kit from different manufacturers. I shall check the Pinout diagrams for each, but IF there are subtle differences I'm assuming the Crimp method is a no go?

Also, been searching online for 25 way ribbon cable and appropriate crimp connectors - where to turn?!!

[Bill@WelcomeHome]

Originally Posted by peeej1978

Also, been searching online for 25 way ribbon cable and appropriate crimp connectors - where to turn?!!

I wasn't the guy who did the work so I don't know about sourcing pieces/parts. But swapping pins would be a different issue. There are two formats of which I am aware and they are different. Could you peal the ribbon cable apart and reorder the conductors, line them up and get them into the connector? Possibly. Meanwhile, the company that makes cables for RME (Avia? something like that...) makes an adapter to swap the pins around. Don't know what it costs but it might be worth it. For me, it was worth buying pre-made cables. I have the skills to solder or crimp, but I just wanted it done and done right and I have a pile of things to solder as it is. When you see what pre-mades cost, and you can find them used, ....