Hi guys
Rel subs have a high level connection via the left + & - and the right + only at the speaker connections on the power amp. They also allow you to have this high level connection and a low level connection hooked up at the same time.
How do I do a high level hook up - REL Strata 5 to a pre/power amp when the pre amp is phase reversing? Practical experience tells me that reversing the positive wires to negative and the singe negative wire to positive will short the power amp. Is this correct (it sounds like it, and I have been told by the amp repair guy that I had been shorting the speaker output somehow).
Now for the long story just to confirm that I am ignorant of all things electrical, even though I thought I understood the basics enough to hook up a hifi.
Originally I hooked up the sub high level connection as per the users manual, then simply pressed the 180 phase reverse button so that my sub and mains where in the same phase.
I should mention that the main speakers are hooked up with the + & - reversed to compensate for the phase reversing pre amp, otherwise they sounded out of phase. This was in accordance with the manufacturer’s recommendation (Conrad Johnson PV14 pre)
Now it gets complicated :-). This is an integrated home theatre and 2 channel system. In two channel mode I only use the pre/power amp (receiver is off) and sub via the high level connection. For movies in 5.1 I use a receiver and the subs low level input and the high level input is also connected. The front two channels run from the receivers pre-outs to the pre-amp which is in "theatre bypass" mode. The pre-amp runs at unity gain, making it almost invisible (but still reversing the phase). This is fine for the main 2 speakers as they are hooked up with the + &- reversed. Unfortunately when connected as per the users manual the sub gets high level input phase reversed and a low level input from the receiver not reversed.
I thought I had the solution by reversing the subs high level connections at the power amp just as I had done with the main speakers (swapping positive for negative), but I think I got that wrong anyway, heaven knows what I actually did. The result was a system that apparently worked, I would listen to two channel (fine), I would watch a movie (also fine), then switch back to two channel to hear instant distortion and other bad sounds so I shut down the system ASAP.
After experimenting to isolate the fault I concluded that I had stuffed the power amp and took it in for repair. I was told I had shorted the power amp at the speaker connections and the output section of the amp had to be fixed. I was also told not to use the high level input as it changes the ohm rating and degrades the sound, however I like the sub in 2 channel filling in the bottom below 38hz on my B&W 804s, that’s why I purchase a Rel in the first place.
After the repair I hooked up only the speakers as before (+ - reversed) and all worked well.
Later I tried to hook up the sub to instant distortion so I quickly unhooked it – this isolated the short to the sub. I tried the high level cable not connected to the sub – that was fine. I plugged in the high level at the sub and turned on the 2 channel power amp(sub still off) - instant distortion. I then hooked up the sub with the wiring as recommended and all was fine, but I now have the high low input at different phases again.
Rel recommend using high and low connections and it has suited my needs to have both connected – “plug in and forget”. It seems to me that I cannot do this as the high and low signals would be in different phases.
Is my only solution to unplug the high level at the back of the sub for movies so that the sub only gets the low level signal. For two channel I plug it back in again and reverse the phase to compensate for the pre. In 2 channel mode there is no low level signal as the receiver is off.
What about the cables from the pre to the power amp. Surely it would not just be a matter of having them modified to reverse the phase before it gets to the power amp – this does not seem right as if it was that simple Conrad Johnson would do that in the pre-amp. They say that they do not correct the phase in the pre as the additional circuitry degrades the sound.
I hope this makes some sense to somebody.
Thanks in advance for your help.
Robert
PS- maybe all this does not matter if set the receiver crossover to small main speakers - that way the high level connection is not getting anything below 80 hz anyway. The crossover on the rel would eliminate anything above its setting of 38 hz - resulting on no out of phase high level signal getting through. Any thoughts?
Rel subs have a high level connection via the left + & - and the right + only at the speaker connections on the power amp. They also allow you to have this high level connection and a low level connection hooked up at the same time.
How do I do a high level hook up - REL Strata 5 to a pre/power amp when the pre amp is phase reversing? Practical experience tells me that reversing the positive wires to negative and the singe negative wire to positive will short the power amp. Is this correct (it sounds like it, and I have been told by the amp repair guy that I had been shorting the speaker output somehow).
Now for the long story just to confirm that I am ignorant of all things electrical, even though I thought I understood the basics enough to hook up a hifi.
Originally I hooked up the sub high level connection as per the users manual, then simply pressed the 180 phase reverse button so that my sub and mains where in the same phase.
I should mention that the main speakers are hooked up with the + & - reversed to compensate for the phase reversing pre amp, otherwise they sounded out of phase. This was in accordance with the manufacturer’s recommendation (Conrad Johnson PV14 pre)
Now it gets complicated :-). This is an integrated home theatre and 2 channel system. In two channel mode I only use the pre/power amp (receiver is off) and sub via the high level connection. For movies in 5.1 I use a receiver and the subs low level input and the high level input is also connected. The front two channels run from the receivers pre-outs to the pre-amp which is in "theatre bypass" mode. The pre-amp runs at unity gain, making it almost invisible (but still reversing the phase). This is fine for the main 2 speakers as they are hooked up with the + &- reversed. Unfortunately when connected as per the users manual the sub gets high level input phase reversed and a low level input from the receiver not reversed.
I thought I had the solution by reversing the subs high level connections at the power amp just as I had done with the main speakers (swapping positive for negative), but I think I got that wrong anyway, heaven knows what I actually did. The result was a system that apparently worked, I would listen to two channel (fine), I would watch a movie (also fine), then switch back to two channel to hear instant distortion and other bad sounds so I shut down the system ASAP.
After experimenting to isolate the fault I concluded that I had stuffed the power amp and took it in for repair. I was told I had shorted the power amp at the speaker connections and the output section of the amp had to be fixed. I was also told not to use the high level input as it changes the ohm rating and degrades the sound, however I like the sub in 2 channel filling in the bottom below 38hz on my B&W 804s, that’s why I purchase a Rel in the first place.
After the repair I hooked up only the speakers as before (+ - reversed) and all worked well.
Later I tried to hook up the sub to instant distortion so I quickly unhooked it – this isolated the short to the sub. I tried the high level cable not connected to the sub – that was fine. I plugged in the high level at the sub and turned on the 2 channel power amp(sub still off) - instant distortion. I then hooked up the sub with the wiring as recommended and all was fine, but I now have the high low input at different phases again.
Rel recommend using high and low connections and it has suited my needs to have both connected – “plug in and forget”. It seems to me that I cannot do this as the high and low signals would be in different phases.
Is my only solution to unplug the high level at the back of the sub for movies so that the sub only gets the low level signal. For two channel I plug it back in again and reverse the phase to compensate for the pre. In 2 channel mode there is no low level signal as the receiver is off.
What about the cables from the pre to the power amp. Surely it would not just be a matter of having them modified to reverse the phase before it gets to the power amp – this does not seem right as if it was that simple Conrad Johnson would do that in the pre-amp. They say that they do not correct the phase in the pre as the additional circuitry degrades the sound.
I hope this makes some sense to somebody.
Thanks in advance for your help.
Robert
PS- maybe all this does not matter if set the receiver crossover to small main speakers - that way the high level connection is not getting anything below 80 hz anyway. The crossover on the rel would eliminate anything above its setting of 38 hz - resulting on no out of phase high level signal getting through. Any thoughts?
