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Just got a pair of used Rogers LS7 speakers from Saturday Audio Exchange. I'm running them on a 100 watt NAD power amp with an HK pre-amp. When I turn the volume up past 9 o'clock, the amp clicks off into what I think is some kind of safety mode -- power light goes from green to red. Obviously I don't know a lot about this stuff. The speakers have 2 pair of contacts on the back of each one for high and low. On each speaker, there are 2 firm wires bridging the two sets together on each contact (plus to plus/minus to minus). I've tried hooking the stereo wire to both the high and low contacts... same result. Guess I'll have to drive back to Belmont and suss it all out on Thursday night. Any ideas? Does Saturday Audio even take returns? I feel silly for not having them hook everything up and do a test run when I first bought 'em last week.

Got no dough... for now -- hmmm... though, you think it's probably the amp and not the speakers?

Adcam, eh? I'll remember that, thanks.

For now, though, Rogers speakers... pretty good brand?

The guy working at the shop was really into them.

Right on.

Thanks for your help, BadComrade.

Man, I was looking forward to cranking the big new record tonight.

Drag.

Hmmm... maybe there's a short in the speakers.

Thanks for checking around.

BadComrade wrote:Here's a page with the schematic for the crossovers, maybe it'll be of some use to you:

http://www.mhennessy3.f9.co.uk/rogers/ls7.htm

Hah, I'm probably going to be training with Mark Hennessy over the next few weeks.

John W. wrote:Just got a pair of used Rogers LS7 speakers from Saturday Audio Exchange. I'm running them on a 100 watt NAD power amp with an HK pre-amp. When I turn the volume up past 9 o'clock, the amp clicks off into what I think is some kind of safety mode -- power light goes from green to red. Obviously I don't know a lot about this stuff. The speakers have 2 pair of contacts on the back of each one for high and low. On each speaker, there are 2 firm wires bridging the two sets together on each contact (plus to plus/minus to minus). I've tried hooking the stereo wire to both the high and low contacts... same result.

I'm assuming you've just got one run of speaker cable & you're not bi-wiring. If you're using bare wires to connect, double check at the speaker & amp end that you've got no pesky strands of wire shorting the connection out. I wouldn't have thought an 8 ohm load would have been a problem for any NAD amp, so like you say there could be some sort of problem with the speakers.

I've had a couple of NAD amps over the years & I can't fault my current NAD integrated.

Rogers speakers are excellent. Very accurate and tonally pretty neutral. They are british, which, for me, means they are good speakers. The Rogers LS3/5A is one of the best small near field monitors ever. The LS-7 must be a bigger version with a bigger woofer.

check the connections as suggested for stray wire strands. did the speakers work fine on another amp? Check the bridged connections on the back of the speakers.

it sounds like something is shorting. if the NAD worked fine with other speakers, I would suspect the speakers. NAD is pretty solid stuff. There must be some sort of short or a bad component inside one of the speakers. You should def. get them fixed. They will sound great.

I have a(n) NAD preamp with an Adcom power amp, which has given me years of trouble free service.

Ben Adrian

If you can't find an easy solution, I'd recommend posting / searching over at pinkfishmedia.net and or world-designs.co.uk about this. There's a whole network of people who've done major rebuilds and even scratch builds based on vintage LS3/5a // BBC // Linn Kan designs. There will definitely be someone who will know the internals of this speaker well and be able to tell you what to look for. Ditto the NAD comments - it's unlikely to be an amp fault. Those things just run and run.