Thumping/popping sound when changing inputs, etc...

I get a popping/thumping sound whenever I change an input or a surround mode...always from the rear right speaker........not real loud, but a little annoying. Unit is only about 2 months old....gotta do a little more research to see if I can figure it out....narrow it down...have been living with it, and surviving, so far........ but thought I would ask here too...anyone had a similar kind of noise when changing inputs or surround modes???
Just curious......

Same problem coming from my sub. See my post. Let me know if you resolve the issue. Mine is very loud, due to coming from sub output. If I disconnect sub-out it does not occur.

I have similar problem. I have a popping sound which comes from my rear right speaker when I change sources or switch to bypass. If me rear amp is turned off, the popping comes from the center channel. Any suggestions?

Interesting that two out of three of us had the right rear speaker involved......I am using a great old but reliable Fosgate 4100 Amp for my rear speakers (never did this before, so I am doubting it is the amp....right now anyway...), with the 755 handling the front three (with built in powered subwoofers) and surrounds.....I can't figure it out....asked Steve about it, and he wants to try all the obvious stuff first.....changing cables, wires, speakers, etc.....haven't gotten that far yet, but seems to be a pre amp thing...just a hunch based on......a hunch!!!!!
Well, with all of us working on this to try and figure it out I think we might actually get somewhere....I will have to try and see what happens when the rear amp is not on....just to see if my center channel starts doing the same thing.
I still love my 950/755 combo...feel like I got a Whole New System!!!! Everything is happier now....
except for that thumping/popping from the right rear.....
Hmmmmm.........

3 of 4. I noticed this immediately on setting it up. It's not loud, just noticable.

[Edit: Let me be more specific. Rt Surround. I don't have any rear speakers. Not sure what the surround mode was. I'll keep an eye on it.]


[This message has been edited by DMF (edited November 18, 2003).]

I just got back my 950 from blue dot upgrade and am noticing the the same popping on my right rear center. When the 2 channel amp(adcom 545) running the rear centers is off. the popping goes away. This was occuring durng cable channel changing and it happened when the iput signal changed from 2.0/0 digital to 3/2.1 digital or PCM. Our HDTV decoder is connected to our 950 via an optical connection. I have not verified that the same popping exists when switching sources (i.e dvd to cable or laser.) Anyone else having similar issues after their blue dot upgrade?

[This message has been edited by coto914 (edited November 25, 2003).]

[This message has been edited by coto914 (edited November 25, 2003).]

Same here. Light pop when switching inputs or surround modes. Definately the preamp.

I am hearing the same popping noise. It just started doing it. Mine is in the right front speaker. It is very distracting. It occurs when changing modes or several seconds after the stopping the source (ie dvd, cd, computer etc.)It does with both coaxial and optical connections. I have changed the wires with no change in the problem. This seems to be the preamp as the source of this problem. There is no popping/thumping noise during playback however only when stopping a source or change modes.

Well, it seems by now that this is a real problem for some, and that it is Pre-amp related. I kinda was hoping everyone had a similar problem, that it was just the way the unit worked, but many must not have such a problem with the "popping" noise. Is it the Pre-amp, or are we doing something different or wrong that others aren't? At first I thought it was because we had separate amps for the rear, or "popping" channel, but now I am not so sure.
Why just some of us and not everyone??? It is an interesting problem....small, not an end of the world type problem, but a little annoying......
hopefully we can figure this one out.....
Back to the drawing board..........

Same here in surrounds. I even get it when running the Test calibration to check all my speakers. Changing amps and cables does not correct problem.

Never had this problem on my 3 950s I owned.

I'm still having this same problem. Has anyone come up with a solution? It's giving me a headache.

I have tried various things to narrow it down........
it does seem pre-amp related, but with so few of us complaining about it I have to figure it might be something else.......
I am not one to do alot of experimenting, but I have tried switching cables, with no results....
I will have to try and switch amps....
Right now I have the 755 running the 3 front and 2 surround speakers, with a Fosgate 4100 amp (200 watts per channel, and a great amp I might add......)running the 2 rear surrounds......the right rear surround is where the problem is.........
Do most of us have separate amps running the "popping" channel???? Or 7 channel amps like the 770??? I don't believe it is the Fosgate amp, but the only way to be sure is the old switch-er-oo........what a pain!!!!
But the "popping-thumping" noise is a pain too....getting kinda irritating, and I would like to find out how to stop it!!!
We gotta keep trying to figure this one out......and, what to do about it.

My 950, and I am sure it is the 950, gives a low frequency thump when changing sources. I have an ICBM between the 950 and a 770. The 950 has all speakers set to large and the ICBM has all crossovers set at 80Hz. If the thump has frequency components above 80Hz, I have not noticed it in any of the loudspeakers as only the subs seem to respond to the thump. I suppose I could disconnect my subs and find out. I have not experimented to find which of the 950 (blue dot) channels may be contributing to the thump. It could be any one or more of the 950 channels, as the all the bass from any channel is redirected to the subs. The amplitude of the thump is not objectionable, so I have just been living with it. Has anyone contacted Outlaw and found out if this thump is to be expected, or is it a defect found only on a few 950's?

I've got it too. I have an ICBM btwn my 950 and Earthquake Cinenova Grande and Audiosource Amp3 (for back surround) amplifiers. I get the thump from by back surround speakers, nothing from the speakers connected to the Earthquakes.
950 is set-up as all Large, Sub on (all x/o set to 120, which shouldn't matter, but someone said the 950 high-pass filters the LFE at whatever the x/os are set to. I assume this isn't the case if speakers are set to Large, but whatever). ICBM x/o is rear and back surrounds: 80hz, center: 60hz, front: bypass for 2-channel or 40hz for HT.

FWIW, the thump really only became objectionable when I connected the ICBM, which forced me to combine both L&R back surrounds into one channel in the ICBM and then resplit the signal at the amp. Makes sense that the resulting thump would be roughly twice as loud. Before I barely noticed.

And, for the record, the thump happens every time the 950 engages the digital-muting. So, if there's a ~3 second silence in between tracks on a CD (and I'm listening via digital instead of analog connection), I'll get the pop. Becomes really annoying during listening sessions, so much so that I've added an external DAC to my list of upgrades. Hopefully after christmas, I'll no longer be using the 950 digital input while CD listening.

Has anyone been able to resolve this problem?

The unit I have behaves this way.

No.......no solutions yet....
I did e-mail Outlaws Service Dept...
this is the reply I received.......

"I would like to discuss the noise you have described, and offer some tips on pinpointing it's source. If the problem is only in one speaker, have you tried another speaker and cable? You would also want to try a different interconnect between the preamp and amp in the suspected channel. Are your speaker terminations tight? Have you tried different outlets? Obviously there are many other variables to this equation, so please contact me at 1-866-688-5292 between 9am and 5 pm Eastern time.
Thanks and regards,
Steve "

All very nice, basic stuff I think most of us have tried.........
I am still baffled.....and it is not going away....it sure is unusual that only a few of us seem to have this problem....if everyone complained that there was a little popping/thumping noise....that would be one thing.....but this makes me think something is wrong with the 950....but what?????
Is it worth the hassle trying to send back in????
Still debating that question......

I have had 2 units that have had this problem. I hear the pop in all the speakers. I'll talk to Outlaw on Monday and see what happens next.

I'm running an H/k 310 as pre/pro with 755 and I got the same popping sound from all 5 speakers, only when watching tv and change channels to a channel that isn't broadcast in DD.This started only recently when I up -graded my directv reciever.I've had the 755 for almost a year and have never heard this popping until the sat upgrade.

miker, your situation sounds like it is related to the new DirecTV receiver, possibly the interaction between the HK and the satellite receiver. If it is happening when the receiver switches from DD to PCM digital audio, it is possible that the HK is unmuting before it finishes re-acquiring the signal. The 755 is far enough downstream that it is not actively involved in the popping -- it's just doing what it's told and amplifying whatever signal it is fed.

As an aside, this could be an example of why Outlaw chose to leave the 950 with a bit more of a delay in acquiring digital audio signals than most of us would like to have -- it minimizes the chance of people picking up "transition noise" from changing processing modes.

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gonk -- Saloon Links | Pre/Pro Comparison Chart | 950 Review

Same problem here - popping whenever the auto-mute circuit kicks in. When it switches modes, too long b/w tracks, even when changing presets on the tuner.

It only occurs with my rear/center amp - a Chiro C-500. The fronts, driven by an Odyssey Stratos, does not thump. I switched amps and the thump follows the chiro. Previously, I've used a Denon receiver as a pre-pro, and no thumps there. It's definitely the pre.

When I purchased thr 950, I went thru the same questions with Steve of Outlaw, and almost sent it back.

I've posted this issue on the Forum pages at audiogon.com , and one person suggested it could be related to leaky d/c.

anyway, let's keep this thread alive and find out what the issue is. I love my Chiro, and am very close to selling it. Can't handle the THUMP much longer!

- Dan

Verification: Dan, you are saying that the 950 is doing something that the Chiro is sensitive to, but which the Stratos is not sensitive to? The Chiro will thump on any channel to which it is connected and the Stratos will not thump on any channel?

If so, and if we knew what the Chiro and Stratos were doing differently in their input stages, this would seem like a great clue as to the nature of the problem.

best bang - yes, it has something to do with the 950's compatibility with the Chiro. The thump does NOT occur with the Odyssey. If this enlightens any of you engineers out there as to possible causes of this extremely annoying problem, please post them.

I did track down the email address to Fred Pham, the head engineer of Chiro before it went out of business, but he did not respond to several emails.

I found some solace in reading I was not alone with this problem, that it is not unique to my situation. I find it curious that no one from Outlaw has posted any comments on this topic. Any way to let them know?

-Dan

I believe I’m having the same problem but I don’t believe it is the 950. I have Comcast cable and a Motorola HD cable box. My first box would shut itself off in the middle of programs for no reason what so ever but I never had the clicking problem when changing from DD to regular broadcast. I finally got tired of the turning itself off problem and called Comcast for a new box. Now the new box doesn’t shut itself off but I have the clicking sound you are describing when I change from certain channels (DD to regular). My first guess is that something in the electronics of the Motorola box is creating a static discharge when I change channels. Any one else running Motorola gear? If not a Comcast cable box maybe a Motorola Direct TV box? Like I said it started when I received the new box so I don’t believe it is the 950. I hope we can pin this down because it is really annoying.

Lasher

It also happend when my hughes direct tv box switches from pcm to dolby digital. this switch may be a bit louder than the other thumps I get over the Chiro channels, but I don't know if it comes out the fronts which are powered by the silent Stratos. Will test and repost.
- Dan

thump occurs when hughes direct tv box switches from pcm to dolby digital in ALL speakers, not just chiro, which means that problem is definitely not the outlaw.

anyone heard anything?

-dan

Hi,
Another possibility is if any input has a DC voltage on it, even a small one (I know...they shouldn't...but stranger things have happened), it will show up as a 'thump' when switching to/from that input.

Peter

It is DC that is causing the pop and it's exhibited by some amps and not others. It's dependent on the amplifier design. This is information I recently received from Aragon tech support. I contacted them because my Acurus amp does not pop but my Aragon does. If there is DC present, the Aragon makes a small thump when changing inputs. The Acurus is a different design and doesn't. It's not harmful to the amp.

My 950/755 combo does not have the thumping noise when changing inputs at all but I get the thumping noise from my surround speakers everytime when I initially turn on the 950/775 set and the loudness of the thumping depends on how high the volume setting.

Peter and seattleguy:

is the outlaw 950 not supposed to send dc output to the amp? In other words, is there something wrong with the Outlaw that there is DC going to the amp's inputs?

Considering you said: "I know...they shouldn't...but stranger things have happened" I wonder whether there is a problem with DC leaking from the Outlaw.

Is there way to alter a DC thumping amp to remove the thump? Or is this impractical/will lessen sound quality of amp...

Lastly, why do some amps exhibit the DC thump and others do not?

thanks for all of your info.

- Dan

I'm no expert but it sure sounds to me like there is a problem with DC leakage from the 950. From what I have learned, if an amp makes the thump there is nothing that can be done to eliminate it. As far as why some amps do it and other don't based on design, I can't answer that. That's way over my non-electrical engineer head.

Anything new in this area?

Run a 2ch Audiosource amp for surrounds, a separate powered sub, and a B&K amp for the 3 front channels.
Being to think I have a problem because I never hear anything when switching inputs/modes.

No one ever figured this one out, ey?

My newer Rotel five channel amp = no thump. Odyssey two channel amp = no thump.
Chiro c-500 five channel amp = thump.

Tried the Chiro with two other processors (the one that comes with the Acoustic Energy Aego system (bedroom system) and a denon receiver being used as a processor. These combos = no thump.

Someone has to know somoething about this! Anyone?