Thread: Unbalanced Interconnect length...

Some of you might know that I have upgraded from my Emotiva XPA-2 Gen 2 amp to a beautiful pair of Odyssey Audio Stratos monoblock amps.

Anyway, I've known for some time that these amps do not utilize true balanced inputs, they are just convenience XLR's tapped into the standard unbalanced RCA connectors. That said, many owners of Odyssey amps claim that unbalanced interconnects actually sound better. This is all fine and dandy except for the fact that I need a 30 ft run of cable to reach from the XP-20 to the Stratos amps.

I've never run unbalanced cables that long other than in car audio, and that was usually 17 ft to 20 ft at most, and with an AudioControl line driver up front right off of the head unit to boost the head unit's preamp voltage (usually 2v t0 4v) up to 9.5v rms (13v peak).

Considering the XP-20 has a max output of 7v (nearly 15v or so around clipping which I would never run my system that hard), I think that I should probably be fine running 30 ft of cable in the house.

My question is, what are your experiences running a good length of unbalanced interconnects in your systems? Did you find one brand or series better than the other?


Since the majority of my cables are Wireworld, I think I'd like to keep with them, and most likely upgrade some of them as well along the way.

Many thanks in advance!

I had issues with a couple of sets of unbalanced cables, one BJC, and the other Zu Audio. I had hum with amp wattage >25 watts with my very sensitive Zu Druid speakers. Same speakers with BJC Balanced cables into a balanced amp (DIY Aleph J) was silent.

As I made more DIY single ended amps, and played with my dads old MC60 mono locks, I ended up getting a transformer based XLR-RCA box from Jensen, and 1m RCA interconnect pair. Worked perfectly. Something you might consider if you end up having trouble with RCA interconnects.

I don't know why I didn't mention it in my first post, but the whole reason for asking about long unbalanced connections vs balanced is mostly due to the fact that our house has some kind of grounding issue, or at least this room does.

When we first bought the house a couple years ago and I quickly installed my system on the first day, I was running the NuPrime STA-9 amps for about a week, running a 1m balanced IC to them from my Schiit Freya+ preamp. The Freya+ utilized true balanced inputs/outputs, but the amps did not as they are like the Odyssey amps in that the balanced connectors are just wired into the RCA connectors.

Also, just like the Odyssey amps, the little NuPrime amps utilized grounded IEC connectors.

In contrast, the Emotiva amp I've been using this whole time uses true balanced inputs as well as a non-grounded IEC connector.

The Emotiva was always dead silent no matter what, but the NuPrime and Odyssey amps pick up buzz (not hum). I've always thought the buzz was coming through the ground in the house wiring, but if I disconnect the IC coming from the preamp, the Odyssey amps go dead silent, however when I did this with the NuPrime amps, they still had that buzz coming through but not as loud.

So now I'm wondering if that buzz is coming through the ground lead in the XLR cables, being that the preamp is balanced and the amp is not. This is what sparked up the whole idea of running standard SE IC's to the amps instead. Well that and the fact a lot of Odyssey owners claim that these amps sound better via standard SE IC's.

Originally Posted by nicoff

In the worse case scenario, if you cannot get rid of unwanted noise regardless what you do, I would consider moving to balanced-designed equipment.

This of course is not an option. These Stratos amps are not leaving this house.

Charles

Did you try a cheater plug on either the amps or the preamp to see if that would stop the buzz? This is not a really uncommon problem with using a balanced preamp and a SE amp. Not an ideal solution but it my give you an idea of where the problem is.

Originally Posted by Jack

Charles

Did you try a cheater plug on either the amps or the preamp to see if that would stop the buzz? This is not a really uncommon problem with using a balanced preamp and a SE amp. Not an ideal solution but it my give you an idea of where the problem is.

Hello Jack,

No, I have not tried that yet. I was looking around for the cheater plugs (I know I have a few of them), but they are M.I.A. Of course, I would only use them as a test. I certainly wouldn't leave them in the system. But yes, I know where you're coming from. I know you don't mean leaving them in.

This is also why I want to try some SE IC's. I have no doubts the XP-20 is equally excellent in both its balanced and SE outputs.

Since the amps are currently plugged (via the extension cable) into the same outlet as the source gear, the buzz is still present but much much quieter, it makes me wonder if I'm getting that noise specifically because I'm running a balanced signal to an unbalanced amplifier(s). Pretty much what you said I suppose, just in fewer words. LOL

That's been my experience with several combinations of that type. It's not always the case but more often than not. Tried a fully balanced W4S STP-SE into a Kismet a while back and had to lift the ground in that combo to eliminate a faint buzz. Also had it happen when I plugged a fully balanced DAC via XLR into a SE preamp and amp combo. Lifting the ground on the DAC solved the problem there. You may resolve it just by lifting the ground on the Pass preamp and that would be preferable. If you are plugging the preamp into some type of conditioner it will pick the ground back up there. Bones13's idea of trying the Jensen transformer may be a solution especially if you can find it on Amazon where you can try it out.

Oddly enough, it never crossed my mind to lift the ground at the preamp. That Jensen transformer seems interesting. Also, the Hosa GLT-255 ground lifter may work. But of course, all of these are just band aids and not truly addressing the issue.

Yes, it may look a bit hokey at the moment and I may not be getting the absolute best performance out of the amps right now, but at least my father's old homemade extension cable has reduced the "buzz" to where you can hardly hear it at the speaker. It's silent at the listening seat. I might as well just leave it as is for now until cooler weather gets here and my electrician friend can come over and install the dedicated lines.

Even if those devices mentioned work, I'd rather not have extra components in the signal chain if I can help it. Of course, as a last-ditch effort, I would go for on of those devices. And heck, for all I know, just running regular SE IC's from the pre to the amps could also solve the issue.


There is one other issue with this buzzing though, that for some reason I have failed to mention yet...

There's this loud buzz that comes through every once in a while no matter what outlet the amps are plugged into. It's the same volume regardless, and it sounds like something that's on a timer or something. It comes on loud (can be clearly heard down the hallway), runs for about 10 - 15 seconds, then turns off. It does this maybe once or two every two hours or so. In the late evenings, it seems to come on and stay on for several minutes, but then shuts off again.

I have no idea what it could be. When I first hooked up the stereo here on the day we moved in, I searched and searched all around the house for the source of that "timer" buzz, thinking if it could have been the irrigation timer, or the unused Fios box in the garage by the beaker box... Both unplugged now going on two years and that buzz still shows up. Maybe the water heater? I have no clue.

Ice Maker?

Originally Posted by Jack

Ice Maker?

I thought that as well, but unfortunately, no.

Originally Posted by nicoff

Well in that case, keep listening to their "buzzing" and don't make a fuss about it!
By the way, didn't Odyssey Audio the manufacturer of your Stratos go out of business?

One way or another, the buzzing will be banished, and it won't be from changing out the amps. Part one of that banishment is the fresh order of BJC LC-1 cables that I just made.

And no, Odyssey is not out of business. Quite the opposite actually. You could have answered your own question with a 3 second Google search.

Funny none of that shows up when I do a Google search for them. Doesn't mention a single thing about them closing... Because they're NOT closed. And I too use the Opera browser.

Not to mention I was literally talking with the man just a week ago on the phone.




More importantly, back on topic...

I spoke with Galen of Belden ICONOCLAST yesterday, and for the money (conserving $$$ at the moment for a couple of extra upgrades including the dedicated 20amp lines for this room), he recommended going with the Blue Jeans Cable LC-1. So last night I ordered a 30ft pair. They'll be here in a couple of days.

I'll let you guys know what happens.

There are so many variants of balanced output and input circuitry that the course of action you are on is the correct one. Hook 'em up and see what happens.

I was thinking... If this works out as planned, should I also switch my Altair G1 over to unbalanced as well?

I mean, what's the point of running only one piece of equipment balanced if everything else is unbalanced, especially when I can use a 1m or less interconnect from the streamer to the preamp?

Plus, that would just be balanced circuitry having to convert over to unbalanced in the preamp anyway. Am I right in this thinking?

Some equipment work in an actual balanced function, meaning they receive the differential signal, and have circuitry for each hot and cold input (cold not being ground). This requires 4 signal paths from input to output, plus a ground plane. One of these units will work best, with balanced interconnects, when connecting to another truly balanced device.

Many “balanced” input or output plugs are the result of an internal transformer, or silicon circuitry creating a differential output, while the actual device runs as unbalanced. Other circuits just ground the cold leg, essentially making the XLR cable an unbalanced connection.

So, if your device is actual single ended inside, either connection would be the same.

Of course, as stated above, trying different things is the best policy, and part of the learning, and fun.

Originally Posted by nicoff

True that. Some manufacturers attempt to make their unbalanced products "look' as if they were balanced designs by adding XLR connections, yet they are not truly balanced designs. It is just a marketing ploy.

First you're trying to tell everyone that Odyssey is out of business, and now suggesting they just throw XLR jacks on their equipment as a "marketing ploy".

Are you done?...

Anyway, back on topic...

The BJC LC-1's came in today, promptly got installed about an hour ago, the amps got moved back a little so the 1m Wireworld power cables would reach the front outlets, each amp turned back on one at a time, feverishly standing by the tweeters on the Maggies, and...

NOTHING! As in nothing but sweet sweet silence!

I have to be honest, I wasn't expecting that. I was expecting to still hear that buzzing, but it's totally gone.

The only downside, that loud buzzing that comes and goes like it's on a timer, still comes through, BUT... It's extremely quiet now. With nothing playing, you can just barely hear it at the listening seat.

So for me, this is an almost total win-win situation.

I want to thank everyone for all of the advice and suggestions! Now I can concentrate on the other needed upgrades. The fun never stops!





A slight invasion. LOL

Those are clearly not happy ears.

Originally Posted by brad225

Those are clearly not happy ears.

That's what my father used to call "airplane ears". LOL!

That's Mr Weasley. I was trying to get him to look at the camera (phone) and I think I accidently touched his back towards the base of his tail, which is a sensitive itchy area for him. In other words, he didn't like it.