Auto on/off Sub = Annoying

I

iwatkins

Guest
Hi All,

My sub powers itself off after a few minutes if it doesn't receive something from the LFE pre-out from my receiver. I understand this is normal and many subs do this.

However, when it does this it does so with an audible click. OK, this is fairly quiet, but still annoying.

Much more annoying is the fact that there seems to be a delay between when the LFE signal picks up again and when the sub starts to amplify it and make it heard/felt.

I.e. you have a quiet scene for 5 minutes, say followed by an explosion/shoot out. I miss the first few seconds of this action as the sub has shutdown. It does restart OK and you get the rolling thunder of the explosion but kind of jolts to get this halfway through the action.

Is there a simple way to force the auto circuitry to stay switched on ? For instance, if I pulled the amp off the back of the sub, would there be something easily identifiable I could remove or a wire I could cut etc.

Thanks in advance for any advice.

Whoops, sub is an Eltax Atomic 10, tis poor but does the duties for now.

Cheers

Ian
 
If you use a Y splitter and use both L & R jacks the sub will detect a lower signal than normal, that's about all you can do really. Panic Room is the sort of film where this can happen and like you say it is annoying :rolleyes:
 
Hi iwatkins
cant you leave your sub turned on 24/7 ive always left my subs on all the time except when iam on my jollys. problem solved.
Gonzo.:)
 
Apocalypse,
Yes, I've already done that, i.e. both sub pre-outs on the amp into a Y splitter (or joiner in this case) and then into the sub. Didn't really help that much. I think the problem is that the sub once it switches to standby requires quite a large LFE signal to wake up again. I.e. small rumbles are not loud enough or long enough to get the sub to wake up.

gonzo,
Yes, the sub is switched on all the time. I.e. the power switch is set to on at all times. It is just that the amp on the sub itself switches itself into standby when it doesn't recieve a large enough LFE signal after a few minutes.

Thanks for the ideas though people.

Cheers

Ian
 
So, your sub goes to sleep when there's no LFE... I suppose it doesn't have a switch to enable/disable auto off? if it doesn't, your options are a) a different sub, b) modifying the amp in the sub, unless somone who actually has one of these subs can offer a solution. Can you post a photograph of the back of the sub and of the amp internals?
 
cybersoga,
No, there isn't an "auto defeat", which is a shame.

I'll pop the amp off and take a look inside/take piccies.

A different sub is on the cards, but I'm saving to get a good one.

Cheers

Ian
 
"A different sub is on the cards, but I'm saving to get a good one."

My Kef TDM45 cost £800 and has this feature, drives me nuts.
 
This is really obvious and you've probably done it already but just in case you haven't try this to minimise the problem:

In you receiver set-up, set the channel level on the sub channel to the mazimum (+10dB or whatever).

Then turn down the volume on the sub itself to match the overall level it was at originally.

This way it shouldn't turn off quite so easily.

Charles.
 
Charles ,
Bit of lateral thinking there, I like it. You say obvious, but I hadn't actually thought of that. :smashin:

I'll actually give it a go as I have the gain on the sub at about 8 (out of 10) and the sub level on the receiver at 0db.

So, I guess if I turn the level up on the receiver to +10db (the max) and then turn the gain on the sub down to get the same volume it should work better.

I'll give it a go and report back. Thanks.

cybersoga
Took the amp off the sub and there is more to the amp than I thought. Loads of wires, couple of transformers, a few circuit boards etc. However a lot of the circuity is encased in potting compound or rubber foam so not easy to trace anything through. I won't bother taking pictures at the moment until I'm tried plan A above.

Cheers

Ian
 
Right, bit early to tell, but it does seem to have made a difference. :clap:

I'll listen to a few more DVDs first, but we may well have cracked it.

For info. I have the sub level on the receiver set to +10dB and the gain on the sub back panel down to 4.5.

Cheers

Ian
 
set speakers to small? Sub will stay on regardless of lfe channel being present.
 
Originally posted by Jeff
set speakers to small? Sub will stay on regardless of lfe channel being present.

Not with films like Panic Room, even the HGS-18 turned off during this film with the speakers set to small.................I've since turned the sub on permanently and use the remote to place it in standby when not in use.
 
set speakers to small? Sub will stay on regardless of lfe channel being present.

Won't help unless you assume there is always some bass present in those channels or you set the x-over frequency very high.
However I am with Charles, increase the level at the AV amp/receiver and in return lower at the sub - this will usually do the trick.
 
I did exactly the same thing yesterday when testing an Eltax sub. (which didn't go off at any time.)

However more to the point, when I put my regular Sony sub back, it sounded twice as good...

So the high amp out setting and low sub volume is performing better that the factory presets - but why should I be surprised at that!

And it never sleeps...
 
The on\off switch on my A10 is in fact a 3 way switch - on\off\auto, when switched to auto it goes to sleep if there is no LFE signal, but it doesnt if its switched to on
 
Hi,
Can anyone tell me how to bypass the auto-on switch so it stays on all the time...Martin Logan Dynamo 500 subwoofer?
Thanks much
 
Hi,
Can anyone tell me how to bypass the auto-on switch so it stays on all the time...Martin Logan Dynamo 500 subwoofer?
Thanks much
Welcome to the Forums!:)

Have you had a look at Post #8 above?

Your Sub is quite old, in that new Subs tend to offer On/Off/Auto as options now. I had a look at an image of the back of yours and I don't see that - it's basically on Auto all the time.

Try boosting the signal at the AV receiver end to maximum and reducing the output at the Sub end, see if that works?
 
Thanks much... But I have tried those settings to no avail. The sub status on at higher volumes... But I often lost to music at lower volumes.
I really need to somehow bypass or disable this "auto on" switch so it stays on all the time... any assistance is appreciated.
 
Corrections: "The sub stays on at higher volumes... But I often listen to music at lower volumes."
 
Corrections: "The sub stays on at higher volumes... But I often listen to music at lower volumes."
Okay, so it does work, but only at higher volumes than you listen to your music, is that right?

Can I ask whether you have your Sub for Home Cinema use or just 2-channel?

I'm sorry, I can't help you. My Sub has On/Off/Auto and comes with a remote control, so I just switch mine on and off when I need it. I don't think having Auto as a default setting is great as it takes control out of your hands, so I can see why you're frustrated.

Keep hunting around online for solutions, I'm sure something will pop up!
 
Another thing you can try, if your sub has a left and right input and you're only using one, you can use a phono splitter and double the input level to the sub, that might help.
 
Thanks. I have tried that and many other configurations and settings.
I really need a way to modify this switch for it to be a dedicated "on" as opposed to "auto-on".
 
Thanks. I have tried that and many other configurations and settings.
I really need a way to modify this switch for it to be a dedicated "on" as opposed to "auto-on".
Apart from this feature, are you otherwise happy with the ML? If so, can you live with this quirk?

If not, perhaps you might consider changing it to a Sub that does offer more than just Auto all the time?
 
Thanks for your reply.
Yes...the ML sounds awesome...when it is on.
 
Thanks for your reply.
Yes...the ML sounds awesome...when it is on.
Okay, well that's at least good!

Right, have you tried to contact ML themselves and see what they suggest? Are there any dedicated ML Forums whereby people post queries specifically about their products?
 

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