Subwoofer issue


#1

I have a subwoofer in my system that I’ve had for 20 years and it has been fault free til now . It was until I got the BHK 250 which replaced a Sugden IA4 class A integrated , the problem is as stated the sub won’t turn off anymore when used with the BHK , it was intermittently functioning ok initially but then would stay on all the time . I pulled the amp out of the sub and there’s nothing looking cooked or suspect , I did notice though a low level hum . I thought I’d get a bit more serious and cleaned connectors and switches etc pulled the lead from the amp ( high level input on the sub ) and I thought that I had it , after pulling the positive from right hand channel out of the BHK , the sub turned off . But for nought tried it again the next day no luck . Anyway cut to the climax , in the end I got the Sugden out and plugged the sub in and it functions fine , turns off after 5 minutes fires up ok etc . What’s different between the two amps , there’s no standby mode on the Sugden , turn it on it’s on turn it off it’s off . Any suggestions or thoughts . Interestingly when using the low level input on the sub everything is fine .

Regards Leigh


#2

My two Rythmik subs are connected to the extra pair of binding posts of the 250 and they turn off as normal with no signal just like using the preamp outputs. What is the sub in question. I suspect that since you are turning the Sugden completely off your sub amp which is sensitive to current is turning off as opposed to the BHK which in standby still has it’s SS section active. The only solution is probably either turning the sub off manually or turning the 250 completely off by the back switch. Actually surprised that a 20 year old sub would have a auto mode as in those days most subs still used AB amps that were also either on or off. I have an ACI Quake sub that would be almost 20 years old and it has a Class AB amp that is either on or off.


#3

The sub is a Ruark Log-Rhythm no longer made of course , they seem to be making radios of various sizes these days , of which I have one and it’s very good ( R4 ) . Besides that there’s been a bit of a development since posting and that is , as there is only so many power outlets in a room the sub was plugged into a circuit that was seperate to the rest of the system and on plugging into the dedicated circuit the sub seems to be behaving as it should , touch wood . This of course creates another problem does this mean that I have to get an electrician in to add another circuit in the STAR wiring method as there only so many double adapters I can get on the back of a P5 . What is that howling noise ? I need at least seven outlets , what does one do ? Thanks Jack


#4

I don’t have the same issue that you have, but it may be related. My REL sub, connected to an integrated amp high level outputs. When the DirectStream DAC is turned off with the amp on, I get a hum in the left channel. BTW the REL gnd is connected to the right channel. If I disconnect the REL cable, the hum stops & if I turn n the DSD the hum stops. You may be seeing some hum when your amp is turned off & that is keeping your sub turned on. Just a thought. I haven’t tried running the REL without the gnd connected.
Cheers,
Kev


#5

Hi Kev , yes you are right the hum does seem to keep the sub on and it’s in the right channel , I thought I had solved the problem but no , now it turns off most of the time but not always , curiously it’ll turn off if there’s a pause in signal , after 5 minutes or so but cannot be relied on to turn of when the power amp is off , so I’ve given up worrying about it . I do know that if I connect to an amp other than the BHK it will function as it should . I’ve tried lifting earths and using shielded cable which is probably a bit dumb given its high level , even reduced the length of the cable . At the moment I’m not using the BHK as it’s too hot 30-39C which is pretty funny given that Colorado is still in the grips of winter , I had a pic sent to me today from Fort Collins of a bottle of window cleaner left in a car o/night , frozen solid , we don’t get any really cold weather even during winter , the odd 0 C as Melbourne is on a bay , Australia ie . Enough of the weather . Thankyou for your comments .
Regards Leigh