"popping" when moving to balanced cables on Amp


Hi all,

I'm a bit perplexed on something. I just got some balanced XLR cables with Nutrik connectors for my Anthem setup. I have an AMV-20 Anthem Preamp and an MCA-20 amplifier. The cables really made the system come even more alive!

When I turn my setup OFF, there is a HUGE POP that now comes from the speakers when the amp turns off. There was no such massive pop when I was using RCA interconnects.

Is this characteristic??????? I don't know what to do and where to begin diagnosing. I guess one could say it's the cables, but that makes no sense?!!!

I haven't had any problems with the amplifier or the pre-amp and turning the volume DOWN before turning the system off doesn't make any difference.

Help!!!! I don't want to damage my speakers.

I have Revel Performa M22's and the Anthem AVM-20 and MCA-20 as I mentioned above. I am using Audioquest Type 4 speaker cable and now I just got new Balanced XLR connectors (.5 meter) from CableSolutions.
internetmin
I would start by checking the wiring of the XLR leads with a multimeter from radio shack...perhaps you have a crossed or open wire, Did you leave the RCA conected too...perhaps you should disconnect the RCA?
I disconnected the RCA first-thing so that I only had the balanced connected. The balanced cables are brand new.

The question is what is normally the cause of this type of "popping" when you turn off an amplifier. I always recall that my audio system had some type of minor "pop" when turning it off, but this is much, much louder.
Dumb question - are you turning the power amp off first, then the pre?
" I always recall that my audio system had some type of minor pop" when turning it off, but this is much, much louder"

Well, you do have more gain using balanced connections...6db, I think?

Dave
The question is what is normally the cause of this type of "popping" when you turn off an amplifier. I always recall that my audio system had some type of minor "pop" when turning it off, but this is much, much louder.
Internetmin

Most of the time the 'popping' sound is caused by a leaky capacitor in the amp. Dave has a good reason it could be louder, the additional 6 db gain that you get from running balanced. Can you take the cables back to the dealer and try another pair? If so do it, if the pop persist then I would say your amp needs some maintenance. If the pop disappears, you had some bad cables.

Best wishes,
John
Thanks for the prompt responses!

What I'm going to try is this:

1) I have the Antem pre AVM-20 and the 2-Channel MCA-20 amp set with triggers. So when I power the AVM 20 pre down it also turns off the MCA-20. I will try turning the amp off first manually and see what that does and then the pre first, etc.

2) I did NOT re-balance my speaker setup since I put in the balanced cables. So I neglected to do that obvious part. If I recall I think I had my setup at a +2 when I did the calibration last on the fronts with the RCA connectors.

3) I got the cables direct from the manufacturer online (so no physical store for me to try out). I will contact them if #1 and #2 don't work.

4) I'm also going to contact Anthem directly re: the capacitor leak that John mentioned.

I've always assumed that "popping" was normal to some degree; however, when I was using my receiver--7.1 Marantz--I never had the degree that I've gotten since moving to separates.

So I'm wondering if there is a trick to separates that a receiver takes care of.

Thanks for the quick feedback.

Ted
Ted, that sounds like a good plan. I didn't realize that you were new to seperates. Amp is always the last thing turned on and the first thing turned off. I have seperates, and no popping at all using this sequence.
Make sure you go through the first 3 steps before looking to the leaking caps.

Let us know how you make out.

Cheers,
John
Thanks john. I just got back from a trip so assuming I can stay awake I will try it out tonight :-)
Ok, now I'm perplexed.

1) I recalibrated all my speakers and took down the L and R about 6 decibels so that they are now at "THX reference" with the balanced connections.

2) I tested a series of sequences with power on and power off and took my amp off the trigger.

3) The speaker "popping" and loud "booming" on startup and shutdown happens when the anthem AVM-20 PRE-AMP is engaged or turned off!!!

4) Turning off the unit with volume down or in mute makes no difference (no surprise)

5) I think that the VOLUME of the boom/pop is lower since I recalibrated the speakers

I'm perplexed?!?!? At this point I'm wondering if the issue is the balanced cables at all or from the Pre-amp and if from the pre-amp why that would be?!!

Any additional thoughts?
No preamp is going to be stable during power up and power down. Internally voltages are changing rapidly and operating conditions for the preamp stages are not established. I would expect some output transients.

It's not your cables. You have to ensure that your power amp is the last thing turned on and the first thing turned off. The trigger does not enforce this.
Disconnect the interconnect cables from your amp completely, leave the speaker cables hooked up. Now power your amp on and off. Is the pop still there? If so, the problem is your amp, if not, then your amp is fine, and the problem is with the preamp or interconnects.

John
ok if I power the amp up last and turn it off first then that solves all popping issues. In other words if there is power to the speakers and I turn the preamp on then that is when I get the popping.

So I would assume that is the issue.

I really want to automate the on off process with a single command. The Anthem amp has an auto-on feature that solves the on sequence but not the power down. Do you all with separates manually turn on your equipment one piece at a time or do you use triggers or what??

I have a Panamax power conditioner that does delayed startup and shutdown but I can't use it with the anthem gear. It blows the fuse because the anthem products have their own internal power conditioners that do not like any others in the chain.

Thanks a ton for all the advice. I think I'm getting closer!!!

Ted
Do you all with separates manually turn on your equipment one piece at a time or do you use triggers or what??

Ted
Internetmin

Yes, I turn all equipment on and off one piece at a time, and I have monoblock amps. :)
No triggers here, I don't trust them.

John
Your Anthem preamp does not consume very much current (about like a 70W light bulb) so you might consider just leaving it on. In my opinion, there is no particular reason to turn it off other than having all the lights off.
I run monos and they are always last on first off. My pre runs 24x7. Source components are a mixed bag. Some run 24x7, others are turned on/off for each listening session.

Power up sequence is always sources then monos. Power down is the reverse. All switching is manual.

If you must have automated turn on/turn off you need a sequencer, not a trigger. These are built into some power conditioners.

Be careful, though. You don't want anything inline with your power amp that might limit its ability to draw AC current. I prefer having the power amps go straight into the wall.

Remember, it's not high end if it's convenient!