GOOD GOD SOMEONE HELP ME!

kingdeezie · « **on:** 17 Oct 2009, 02:25 am »

So, I purchased a Response Audio Preamplifier used from someone on audiocircle to go with my Stratos Extreme SEs.

I got it in the mail, hooked it up, and it didn't work.

The horrible thing though, is that it was causing me to get shocked anytime I touched anything that was connected to the system.

I figured it had to be broken, and I sent it back to Bill at Response Audio to check it out. He checked it out, and found nothing to be wrong with the preamp.

He sent it back to me and I received it tonight.

I hook it all back up and still nothing!!

Again, I am getting shocked.

WTF right?

So, I decided to try the preamp with another amplifier.

I hook everything up to my Emotiva XPA-5, and it WORKS!!

So something has to be wrong with the Stratos amps right?

Well, no, because I then hooked the Stratos amps up to my reciever and it was working fine!

So it has to be some sort of grounding issue between the three units right??

How the hell do I fix that?

You can't kill the ground on the Stratos right?

I don't know what to do.

I can't replace EITHER of these things right now, but they don't function together...

WTH!?!?

HELP!

droht · « **Reply #1 on:** 17 Oct 2009, 04:05 am »

Road trip to Indy with the gear to see Klaus.

kingdeezie · « **Reply #2 on:** 17 Oct 2009, 04:37 am »

While that may be a sweet idea in theory, I think I live something like 10 hours from Klaus....

Plus, I don't know if I am going to be able to repeat the issue somewhere else, since it seems to be system dependent.

There must be some sort of large ground loop issue between the Stratos and the Preamp....

I tried killing the preamp ground and the amplifier ground and all it does it create this MASSIVE humming.

Is this just going to be an incompatibility issue where I have to get rid of one??

I tried calling Klaus with no success, so I am hoping maybe he reads the internet tonight...

droht · « **Reply #3 on:** 17 Oct 2009, 05:03 am »

Sorry king, thought you were in Chicago for some reason.

mjosef · « **Reply #4 on:** 17 Oct 2009, 05:06 am »

Sounds like one of the components power leads might be reversed in relation to the other...
Justa' thought.

Bill Baker · « **Reply #5 on:** 17 Oct 2009, 04:55 pm »

Quote

Sounds like one of the components power leads might be reversed in relation to the other

I have thought about this but usually AC polarity will only effect noise and should not create a compatibility issue

I have a few different power cords that I use at the test benches and systems. Some of them are built with reverse polarity as I go through and measure all components with both polarities to find what arrangement provides the quietest and best presentation. There was a write up on this procedure several years back in Stereophile. This is a no cost system tweak that can make a world of difference.

I am interested in hearing thoughts from Klaus on this as well....

Wayner · « **Reply #6 on:** 17 Oct 2009, 05:12 pm »

Take an ohm meter and touch the 2 surfaces (one probe on each spot) that you are getting shocked with an read the voltage. It will be AC. Report back on the voltage.

Wayner

Occam · « **Reply #7 on:** 17 Oct 2009, 07:14 pm »

Kingdeezie,

Do you have anything like a power conditioner or strip between your wall outlets and your components?
If so, what specifically?

Have you checked the wiring of your wall outlets for proper connections? If you don't know how to do this with a multimeter, you should do this with an outlet checker from a hadware store. It will have 3 LEDs that indicate wiring status -

-Paul

BobC · « **Reply #8 on:** 17 Oct 2009, 07:44 pm »

I assume when you've hooked it up, the receiver is totally disconnected? Like not even plugged in.

So straight stereo: source > pre > amp > speakers?

kingdeezie · « **Reply #9 on:** 18 Oct 2009, 03:43 pm »

Thanks for the replies everyone!

So, I am almost 100 percent sure that it is indeed a ground loop problem. I was researching ground loops last night in detail and I have read several times that sometimes the problem is so great that it can cause electrical shock hazards (

) and high levels of voltage traveling through the interconnects.

I assume that this voltage that is present in the interconnects is what was causing the sound issues since the musical signal is low level.

I tried every variation with pluggin these things in to each other. I tried one amp at a time, into different plugs, using different power cords, using cheater plugs, removing surge protectors, etc, etc, etc, etc....

Nothing worked to resolve the issues. After getting consistently shocked and having other things attached on the circuit, but not attached in the equipment chain shocking me, I called it quits.

I removed the Stratos amplifiers from the equation..

I put in an Emotiva amp that I was using for center channel duty....

The sound right now is pretty heavenly considering that I am without my beloved Stratos amplifiers.

This Response Audio preamp is NO joke; probably my preamp for as long as it lasts; which considering its build quality should be decades. Its so natural and smooth, while at the same time being very dynamic and tactile.

I only wish I could get my Stratos back into the chain....

What does anyone think about an Isolation Transformer like a Jensen?

john1970 · « **Reply #10 on:** 18 Oct 2009, 04:13 pm »

I have never used an Isolation Transformer from Jensen, but I will be ordering two shortly to deal with grounding loop issues with the preamp outputs on a Marantz HT Receiver. Jensen has published several whitepapers on grounding loops:

http://www.jensen-transformers.com/apps_wp.html

Maybe they will help you troubleshoot your problem. Good luck. Just trying to help.

Cheers,

John

kingdeezie · « **Reply #11 on:** 18 Oct 2009, 06:57 pm »

I wish I could get a hold of Klaus!!

I am curious if he thinks its something he can fix, or if its just bad luck and I need to look elsewhere...

Maybe if he can fix it, I'll have him upgrade them out to kismets

It would be a shame to lose them. They beautifully built.

ddgtr · « **Reply #12 on:** 18 Oct 2009, 08:34 pm »

Quote from: john1970 on 18 Oct 2009, 04:13 pm

I have never used an Isolation Transformer from Jensen, but I will be ordering two shortly to deal with grounding loop issues with the preamp outputs on a Marantz HT Receiver. Jensen has published several whitepapers on grounding loops:

http://www.jensen-transformers.com/apps_wp.html

Maybe they will help you troubleshoot your problem. Good luck. Just trying to help.

Cheers,
John

I bought a Jensen IsoMax transformer to deal with a ground loop between my Velodyne sub and Pass Labs amp. For the life of me I could not get those two to be nice to each other. I EVEN drove my 15" sub, Candela preamp, Dac and the 120lbs amp over to the Pass Laboratories and they couldn't figure it out as the amp was functioning properly...

I also have a dedicated 20 amp circuit which everything is plugged into.

While each case is different, in my case the Jensen did not help. Again, it is definitely worth a try though as Jensen is a reputable company. I ended up using the Jensen anyway to go RCA to XLR.

The thing that solved my problem was introducing an active crossover (OF ALL THINGS!!) into the mix. All XLR in/outs, from Candela into crossover then out to the sub and amp separately... It freaking got rid of the slightest hum and my system is the quietest it's ever been. I also noticed no change in sound quality which for me was huge because I had dialed in my system just the way I wanted!!

king, don't give up as eventually you will figure it out. At times I thought I had everything figured out but almost always I would find something I had not thought of previously.

Plugging everything into one outlet, with or without power conditioner, trying different power conditioners, running an extension cord from a different outlet, changing cables, interconnects even if they work with other components, add one component at a time, use cheater plugs for troubleshooting purposes, use a multimeter as suggested above and so on.

Do keep us posted as we can all learn a lot from this...

Danny

Wayner · « **Reply #13 on:** 18 Oct 2009, 08:38 pm »

If your getting shocked, it's more than 4 or 5 volts found in the interconnect. This sounds like a power supply problem that has energized your chassis to the point of being unsafe, IMHO.

Wayner

kingdeezie · « **Reply #14 on:** 18 Oct 2009, 10:54 pm »

So, I talked to Klaus, and it wasn't good news to me at all.

He listed me a few options to try, but then concluded that it could likely be two things.

One, its something in my house. I don't know how this could be though. Like I said, the Stratos amplifiers have worked before with another preamp, and I have been running them over a year with no problems except for humming. Klaus suggested that I take everything to someone else's house and try it. My father is an electrician, and we have run seperate lines for my audio equipment; I would bet on it not being a house electrical system issue.

Two, Klaus wants me to send everything out to him; the amps and preamp included.

I truly appreciate the offer, but that would be a lot of hassle, and I would be out a system for weeks/months.

I have a lot of parties and gatherings coming up at my house in the next two months, and need (really really want) to have some sort of system set up.

While the Emotiva is not the greatest of amps, it works with the preamp and makes pretty good music.

I'm still thinking about what to do at this point.

Anybody looking for some upgrade Stratos Extreme SE +s for cheap?

Doublej · « **Reply #15 on:** 18 Oct 2009, 11:14 pm »

Have you tried it on the non-audio line in the house to see if you still have the problem? I would definitely try that if you can't bring your gear to a friend's house.

Also isn't there some way to check the ground spike on the line to make sure it's properly grounded?

Three, you could connect one piece of gear to the audio line and the other piece to the non audio line.

Four, you could consider getting a couple of three prong to two prong cheater plugs. You can file down the large ends so you can reverse them to see if some combo makes the problem go away. I would do this only as a diagnostic. I would not operate my equipment that way.

Lastly, you could borrow a power conditioner or UPS and see if plugging everything into it makes a difference.

kingdeezie · « **Reply #16 on:** 18 Oct 2009, 11:18 pm »

I've tried everything as stated above with absolutely NO luck.

Its some weird ground loop issue between the two units that is causing the problem...

The preamp into the Emotiva is DEAD quiet; like nothing is on.

Doublej · « **Reply #17 on:** 19 Oct 2009, 12:48 am »

Then as others have mentioned I would spend some time on the Jensen Transformers Website. They appear to have a detailed white paper on how to go about troubleshooting problems and if necessary products to address the issue.

The troubleshooting guide is located at http://www.jensen-transformers.com/an/ts_guide.pdf

It looks like for $12.50 you can get a set of test adapters to conduct further investigation.

(TA-R1 -2 RCA to RCA Test Adaptors with Troubleshooting Guide)

BobC · « **Reply #18 on:** 19 Oct 2009, 01:19 pm »

I had a ground loop problem...turned out that it was a bad thing to connect both my pre and my receiver LFE out to a sub using a y connector. Could your loop be caused by something like this?

I read your post to mean that even with just a straight through source > pre > amp > speakers, with everything else disconnected yous still get shocked. Wierd.

kingdeezie · « **Reply #19 on:** 19 Oct 2009, 01:55 pm »

Maybe I am being difficult, but I don't think audio equipment should be this complicated.

I am sure its something system specific.

I think at this point I am going to send the amps back to Klaus, have him give them a clean bill of health, and I'll likely sell them.