ARC LS 25 Mk 11 Bypass


I'd like to get better "2 channel" performance out of my HT system (Bel Canto Evo 6 amp and PrePro processor, Theta CD transport). When I was at my local stereo store the salesperson recommended that I simply purchase the LS 25 Mk II. He told me that it has a "bypass" feature that will allow me to use the LS for 2 channel music and the PrePro for HT and multichannel applications...without having to move cords everytime I want to move between music and HT. I've tried to find literature on line that would explain how the wiring would work, but I've been unsuccessful. Has anyone out there done this with the LS 25 or some other preamp? If so, did you find the 2 channel sound to be substantially better than simply running it through the processor?
Thanks everyone.
riccap
I have and it does make quite a difference. Another issue to think of though is whether you actually want to mix HT and a music system. I have, and regret it every day. Screws up the imaging to a good extent, but worst it changes the dynamics of the room as the sound room becomes a media/play room for the whole family. I truly believe that the sound room should be a refuge. My 14 year old daughter is in there with her friends whenever my son is not. My 20 year old son has every known video game console in there and a satellite TV receiver with a hard drive. Add to all this the hard drive from the computer, also in the room, and you have to wonder why we all try for a great s/n ratio and quiet tubes with no rush and the like with all the whirring sounds around.

I started a second system, but that is another story and I have soon found out that whenever someone is in the basement sound room (despite all the sound abatement installed when building it)enough sound leaks out to make listening in the living room immediately above it a PITA.

So, word to the wise...
I did this exact application with a ARCLS25MK2 about 3 years ago. I used a Theta Casablanca home theater processor, and fed the left front channel and the right front channel outputs (via XLR cables) from the CB into the "By-Pass" inputs of the LS25MK2. I then, obviuosly, connected my CD player direct to the ARC preamp, and from the LS25 out to my monoblock amps, and finally to 2 front speakers. On the remote for the LS25, there is a button that i recall read "Pass Through", as in to pass an incomming signal (from your HT Processor) through and out the preamp. You hit that button and it switches inputs on the back of the pramap to the Home Theater By Pass Input and simply routes that input out the main outputs of the preamp with out touching its volume. You HT Processor still has complete control over volume.

If Music is your main concern, I am going to go out on a limb and make the statement that with out question, if you have a good cd player (high end DAC's), you will always get better sound running it through an analog 2ch preamp versus running it into ANY home theater processor, regardless of cost. I also really like the ARC LS25MK2, but there is 1 potentially big drawback if you really care about home theater. When running home theater through a 2 channel analog preamp, most preamps, including the ARC ls25mk2, will be processing to some minor degree the signal and thus degrade it. With the ARC LS25, home theater front right and left DID sound worse running throught the ARC. Not horrible, but just not as good as running from the processor directly to the amps. I easily lived with it because my only critical concern was 2 channel, but you can easily hear the difference between running the processor direct vs. running it throught the LS25MK2. On the other hand, my 2 channel setup sounded marvelous comming off the LS25.

FWIW, 12 months ago i replaced the ARC with a VTL7.5, and ran it in the same hometheater by pass mode. With the VTL, I could not distinguish a difference in home theater. I guess for 13K, it had better darn work well!!!!!
you would connect the pre-amp left and right outputs of your HT processor to the "Processor" input on LS-25(either single-ended or XLR). After that's done, there is a front panel toggle switch on the 25 to activate the processor loop. I wouldn't worry about degrading HT performance. Just use same good cables you were originally using with your HT processor and that'll do.