Al, that is very interesting. I think the amp is balanced,and I do connect the subwoofer (REL) as suggested. I will experiment with removing the sub...hopefully this will solve the heat issue. In order to connect the sub, do you know what is the correct way to do this? Thanks. |
Al, thanks for the excellent response. I am hoping that the amp is not damaged by the prior hook-up procedure ( which was approved by my REL dealer!). The main issue is going to be finding a hook-up for the ground wire from the subwoofer to a point on the amp. There are no screws on the chassis that I think will allow for this. I also use the single ended RCA's as the inputs. I will have to experiment a little. Thanks again. |
Hi Al, I have looked at the back of the amp, all of the screws are recessed and seem to have a specific job regarding the amp structure. ( I am concerned that loosening any of them could be problematical as to what they are connected to inside the casing). I will see if Cardas does offer this kind of adapter...hopefully,it would solve the problem. I am also planning on contacting the factory as the amp still runs hot ( I am concerned I have damaged a resistor, as you have stated). ( Although the sound seems to be ok). I will also ask them what is the hook-up protocol given the balanced aspect to the sub. This is so crazy, and I am kind of annoyed at the dealer who failed to alert me to this issue.
Thanks. |
Thanks guys, I am not comfortable with wiring up XLR connectors. So, my next option is to ask the factory how the heck one is supposed to use this subwoofer with their 'balanced' amp. I have never used the amp in the balanced mode, my preamp is single ended. Frankly, I have never seen a need to go balanced in my home. As a former pro musician, we would run cables that were lengthy to our gear....across full stages etc., these cables were 40-60' in length. The cables were not that well insulated and I can see how running balanced was beneficial. In the home environment, where I am running cables that are what...1.5meters typically ( and VERY well shielded) I just don't get it. The extra expense and hassle for balanced..why??
Now with this issue, I really don't get it!
Main question is have I damaged my amp due to the subwoofer hook-up. It seems so based on the heat it is now giving off.Ugh.
Al, one more question...could I connect the ground wire from the sub to my preamp, with the other two connections going to the amp? The preamp has a ground connector for a turntable, which I use for that purpose; could I hook up the sub ground there too? |
Hi Jim,
I disconnected the sub last night and the amp still runs hot. Sound seems to be ok, but I am now concerned that continuing to run the amp may do some damage.
Thanks. |
Hi Al, I will try your suggestion with my multimeter.
What is a little odd, is that the amp still sounds pretty good. Last night I played it for about 1 1/2 hours ( without the sub connected) and it seemed fine, except for the heat issue. No hums, no out of the ordinary noises, nothing to indicate an ongoing problem. Anyhow, like you say, I think a trip to the factory for diagnosis and repair is warranted.
Many thanks again. |
Well, I measured the impedance as you suggest, Al. The subwoofer measures appx. 100 ohms...while the amp is all over the place..too weird!
Both channels seem to fluctuate..what the heck? |
Thanks Al, That's great. I am actually re-thinking your idea about the XLR plug. I can indeed buy one cheap from Parts Connection and it would be easy enough to connect the ground wire to it. One question, is the xlr ground active when I am using the single ended inputs to the amp? There is a xlr switch on the amp that has to be activated in order to utilize the xlr inputs, which would not be in place since I use the RCA's.
OTOH, as you mentioned, I still believe the amp has an issue, so it will need a service. Luckily, while it is gone, I have my tube amp...an ARC D70Mk2 to fall back on. This amp is absolutely superb...I was listening to it last night; I won't be missing the ss Rowland that much while it is away, LOL. |
So, after taking the reading as you suggested Al, i read 0.4 ohms on the right channel xlr input and a fluctuating reading on the left channel xlr input. When I took the measurement between the AC safety ground and the xlr, the right channel was also 0.4 ohms and the left fluctuated all over. I switched the xlr/rca switch on the amp and the results seemed to be the same.
Thanks again. |
Al, the reading at the two RCA's is 0.4 ohms, same as at the two xlr's.
I took the caution of replacing the battery in the meter today ( even though apparently the old one was ok), which seemed to slightly solidify the readings, so I re-took the reading at the left xlr and rca ground, it fluctuated a little but I suspect the true reading is also 0.4 ohms. Seemed to float around there. |
Thanks again Al. As soon as the amp comes back from the factory, I will connect the sub as suggested. Appreciate all the help. |
