You are not logged in. [Log In]


Forums » General Discussion » Technical Questions » Anoying humm in my LFR1100

Page 2 of 3 < 1 2 3 >
Topic Options
Rate This Topic
#406289 - 07/21/14 08:38 PM Re: Anoying humm in my LFR1100 [Re: MatManhasgone]
Gr8_White_North Offline
connoisseur

Registered: 07/12/09
Posts: 2231
Loc: Whitehorse YT
I drop kick test all my parcels prior to shipping. Like you say, you don't know what some whiny baby is going to do to your parcel. Best to let the guy that built it figure it out, since you have done all you can on your end.


I will share a little story with you. I bought a high end Phono preamp (1g) and it hummed like a mofo, I hooked it to my Yamaha, my Denon and my 35yr old pioneer and it still hummed like a mofo. 3 different systems entirely, I sent it back and they said it was perfect, dead quiet and it was reputable brand. I bought a different brand and it hums too, though not to the same degree mind you ,go figure. I wrote most of it off to old house wiring syndrome. Also there is so much damn electronic interference in a house these days , god knows what is doing it.I managed to reduce it down to a manageable amount using a few tricks here and there.

Keep us posted, always good to know how things work out.
_________________________
DOG is GOD spelled backwards.
What others think of me is none of my business.
M80 V3 MY GLOSS Cherry

Top
#406296 - 07/22/14 09:25 AM Re: Anoying humm in my LFR1100 [Re: MatManhasgone]
Andrew Offline
Axiom Engineer
local

Registered: 12/18/01
Posts: 275
Hi Matt,

Can you describe exactly what your system consists of and how you have it hooked up to the LFRs/DSP? From what you are saying it sounds as if there is a ground loop issue in the connection of the DSP to your amplifier(s). The DSP box itself is earthed, but the signal ground is floating, so it in and of itself can not cause a ground loop. However, because all 4 outputs share a common ground, there could be a grounding issue if you are using more than one amplifier to power your pair of LFRs. In that case the loop exists between the two separate amplifiers.

Thanks,

Andrew

Top
#406303 - 07/22/14 04:39 PM Re: Anoying humm in my LFR1100 [Re: MatManhasgone]
MatManhasgone Offline
aficionado

Registered: 05/06/14
Posts: 986
Loc: Lost in the great wide yonder
I have an Anthem MCA5, so there are 5 channels inside the one unit.

I have tried 3 different pairs of RCA cables just to make sure that it isn't the cable itself that is causing the humm.

The LFR1100 speakers are connected to the front and surround amps on the back of the MCA5. (plugs 1,2,4 & 5) The remaining plug 3 is the marked as the center channel amp.

If I have just the LFR1100 speakers hooked up to the amp, and turn it on, it sounds fine. (No real decernable humm).

As soon as I run an RCA cable from the DSP (left or right out) to the input for those respective channels on the MCA5, there is a noticeable humm that you can clearly hear from 5-6 feet away. The DSP does not even need a power cable pluged into it, nor does it need to have power, or turned on for this to happen. Just the simple fact of having the DSP outputs plugged into the amp. You don't even need the pre-out even plugged in. So I have concluded that the fault must be inside the DSP.

I will admit that most of my latter testing was exclusively with the left channel, but I had noticed it with the right before I started doing cable swapping.

I have not tested it with the XLR type cables as I was told by Brent that it should work best to stick with one type of cable or the other, and my pre-out doesn't do XLR. (the amp and the DSP does have that option).

As per Brents instructions, I have packed it back in the box and was waiting for a return lable, but I can pull it back out if you want me to test more.

I can ask my neightbour around the corner if he has some spare XLR to XLR cables hanging around to test with if that would help?
_________________________
Anthem: AVM60
Axiom: ADA1000, LFR1100, VP180, QS8, EP500, M3, M3comp
AudioSource: Amp One/A

Top
#406304 - 07/22/14 05:35 PM Re: Anoying humm in my LFR1100 [Re: MatManhasgone]
CatBrat Offline
axiomite

Registered: 08/05/09
Posts: 6015
Loc: Milky Way Galaxy
Sometimes my cat thinks there's an annoying hum coming from me when I'm busy doing something.

Top
#406317 - 07/24/14 09:31 PM Re: Anoying humm in my LFR1100 [Re: MatManhasgone]
MatManhasgone Offline
aficionado

Registered: 05/06/14
Posts: 986
Loc: Lost in the great wide yonder
We have made a move forward. I managed to have a chat with Andrew, that led to another chat with Sonic Frontiers who makes made my amp. The conclusion was that I was using RCA cables and the DSP's floating ground that makes it more compatible with most amps, made it not so friendly with mine.

So the going conclusion was that when I asked here if I should go with XLR vs RCA cables, the correct answer for me was XLR. I borrowed a neighbours pair, and you can hook them up with ZERO noise from the amp and speakers with the DSP turned off and plugged in. Where before I got a pretty loud hum.

But as soon as you turn on the DSP, I have gone from a humm now to a hiss. New sound.
_________________________
Anthem: AVM60
Axiom: ADA1000, LFR1100, VP180, QS8, EP500, M3, M3comp
AudioSource: Amp One/A

Top
#406319 - 07/24/14 09:59 PM Re: Anoying humm in my LFR1100 [Re: MatManhasgone]
Gr8_White_North Offline
connoisseur

Registered: 07/12/09
Posts: 2231
Loc: Whitehorse YT
That does not seem like an acceptable resolution. Can one of the 2 companies modify their respective product.
_________________________
DOG is GOD spelled backwards.
What others think of me is none of my business.
M80 V3 MY GLOSS Cherry

Top
#406321 - 07/24/14 11:40 PM Re: Anoying humm in my LFR1100 [Re: MatManhasgone]
brwsaw Offline
connoisseur

Registered: 10/12/12
Posts: 1781
Loc: Canada
Is the hiss still with no content playing or components connected/powered?
_________________________
Thinking about co-locating my 4 powered Paradigm subs between my LRR and my LR.
A tower of power.

Top
#406322 - 07/25/14 07:03 AM Re: Anoying humm in my LFR1100 [Re: MatManhasgone]
MatManhasgone Offline
aficionado

Registered: 05/06/14
Posts: 986
Loc: Lost in the great wide yonder
the hiss is with no content playing. its no longer that 120hz humm so it's kind of like the sound you get at the beginning of a record where there was no sound playing but you heard something. hard to explain.
_________________________
Anthem: AVM60
Axiom: ADA1000, LFR1100, VP180, QS8, EP500, M3, M3comp
AudioSource: Amp One/A

Top
#406323 - 07/25/14 10:02 AM Re: Anoying humm in my LFR1100 [Re: MatManhasgone]
brwsaw Offline
connoisseur

Registered: 10/12/12
Posts: 1781
Loc: Canada
Is the volume turned down/off?
_________________________
Thinking about co-locating my 4 powered Paradigm subs between my LRR and my LR.
A tower of power.

Top
#406325 - 07/25/14 01:40 PM Re: Anoying humm in my LFR1100 [Re: MatManhasgone]
Cohesion Offline
local

Registered: 03/27/12
Posts: 282
Loc: Maple, Ontario, Canada
It sounds like you need to call Axiom support again. Perhaps there is a problem with the DSP after all!

Top
Page 2 of 3 < 1 2 3 >

Moderator:  alan, Amie, Andrew, axiomadmin, Brent, Debbie, Ian, Jc 
Forum Stats

15,238 Registered Members
15 Forums
24,017 Topics
424,290 Posts

Most users ever online:
883 @ 03/04/17 05:06 PM

Top Posters
Ken.C 18044
pmbuko 16437
SirQuack 13571
CV 11677
MarkSJohnson 11437
0 registered ()
47 Guests and
3 Spiders online.
Key: Admin, Global Mod, Mod
Newsletter Signup