Auto-power problem

[hypertech]

I just picked up a DefTech Pro 80 sub to add to the HT I finished installing this weekend. I know an 8" is small by most of your standards, but it really rounds out the sound from my smaller speakers and has a bit of thump for the loud scenes in the movies.

Anyway, it is supposed to automatically turn itself on and off based on the signal it is getting from the receiver. It does turn itself off just fine,but the problem is it occasionally shuts itself off and hasn't yet turned itself back on.

By unplugging and replugging the RCA jack, I can trip the circuit to turn itself back on. The signal is definately there because it starts playing right away and sounds good.

So, have I hooked something up wrong, got a defective unit, or something else?

 

[MDS]

It's possible that your rca connector on the cable doesn't make a nice tight fit since the sub will turn on when you reseat it, but I would say it's something else.

Have you calibrated the sub level? What is the volume level on the sub and the volume level on the receiver's sub pre-out? If the levels are too low, it may not trigger the auto-on circuit. Just as an experiment, turn up the level on the receiver and see if it helps the situation. Most of the time you want the sub level on the receiver to >= 0 to make the auto-on work reliably.

 

[corysmith01]

MDS beat me to it. That's what I was going to suggest. I had the same problem with my sub. I'm in an apartment and can rarely turn it up...and with it fairly low, the signal was never strong enough to trip my sub. I boosted the sub level to +4 db in the receiver and then compensated by turning the sub volume down a little. Worked like a charm. No problems with it not cutting on now. Give it a shot.

 

[hypertech]

I thought I tried that, but I've tried so many things, perhaps it got missed in a blur. I'll crank it on the receiver and turn it down on the sub a bit. I've got a townhome and am waiting for the compliants I have to be careful how loud it gets as well.

 

[Votrax]

In my experience the few subs I've owned the auto feature doesn't work very effectively. There always seems to be a delay and I find it annoying to hear the relay clicking as it energizes/de-energizes, so I just leave my sub on all the time. I can't speak for all sub manufacturers as some may employ better auto on/off circuitry.

 

[RLA]

I've got a townhome and am waiting for the compliants I have to be careful how loud it gets as well.

Hello
This artical may help you
http://www.audioholics.com/techtips/setup/avhardware/AudioSetupTips.php

 

[j_garcia]

If the voltage is too low and it has a R&L input, use a Y splitter to feed both inputs. This will raise the voltage seen by the sub slightly and generally works for something like this. Some subs will go to sleep while you are watching a movie if the voltage drops too low. My previous sub, an HSU VTF-2 would do this with movies that had long passages of dialogue and little action, and splitting the signal fixed it 100%.

 

[jcPanny]

Voltage to auto on

To increase the voltage to the sub, you could turn down the gain control on the sub, and recalibrate the sub level on your receiver which will increase its output level.
The sub will be producing the same SPL levels, but it will be getting a higher voltage from the receiver to trigger the auto on feature.

 

[hypertech]

The sub has hi livel speaker inputs, RCA for L/R, and a LFE input. I'm using the LFE input connected to the sub output from my receiver.

You're thinking I might do better by splitting the subout and putting it into L/R on the sub instead of LFE?

 

[jmanlp]

Same exact problem with my velodyne vx10 was pissed cause I thought I just had a broken sub, but I just needed to up the line level and turn down the gain. bingo, same level of sound when its on and it stays on and I dont have to "replug" it to trip the circuit.