2 REL Strata Subs and Mono amps

Zormi, I would like to know what your main speakers are, because I believe you have a totally different problem to Jdolgin, and it hasn't been addressed: you have an active crossover in your system (Krell Phantom's crossover board option) and RELs aren't designed for this; they are supposed to 'augment' the main speakers from below their natural roll-off frequency, without the use of a crossover like the Phantom's. If this is the case (unless you already purchased the subwoofers), you don't need REL Gibraltars as there are many good and less expensive alternatives, some of them with room correction built-in. On top of that, if your main speakers are full-range floorstanders, you don't need the Phantom crossover to use the RELs; if they aren't full-range and depending on their bass response, you can go either way.

Thanks for all of your input.
My issue deals with the specific nature of my Audio Research VM220 Mono Bloc
amplifiers. They accept BOTH balanced and single ended inputs with a toggle switch selecting the appropriate configuration. So....I'm not clear if this specific amplifier uses a differential circuit when running balanced. Also am I safe using the black speaker binding post if running single ended? Overall, a confusing mess. It's not clear if the chasis screws can provide a safe ground connection.
Of course I called Audio Research a number of times and have not gotten a call back. This is a similar experience other Audio Research owners have had since their sale.

Can any one help?

Thanks

Jdolgin, I do not have a circuit diagram with me and won't have it till I'm back at work on Tuesday. The problem is...I believe, both the 0 and 4 ohm taps are both chassis and speaker ground. Some ARC amps come off of chassis ground by 10 ohms. That may or may not solve your problem. I don't remember if the balanced input ground is wired the same way. I can contact the factory for you on Tuesday and ask them. Happy New Year!

Hifigeek,
Many thanks.
It's just so frustrating to get no tech support from AR after so many years as an owner of MANY of their products, and, having had such good customer service over the years.

I guess nothing stays the same.
Other than audiophiles supporting one another.

Happy New Year to you as well.
All the best.

J Dolgin

Very nice, guys, I learned a lot from you last 24h...

Al, I think I was told everything I needed in this particular situation that I simply did not know. Tnx once again. I am gonna write to Krell these days...

Vladimir, my main speakers right now is a pair of B&W 805S, but this is a temporary solution rather than long-term choice. When budget allows, I will probably go with higher class speaker - Focal Utopia Diablo, for instance (use to own Utopia Micro Be - fabulous speaker), maybe Dynaudio Confidence C1, but - addressing to your question - whatever I choose, it will be a standmount, almost for sure (room size issue). Certain possibilities to try Magnepan 3.7 pannels, which deeply impressed me, but I am sceptical due to room size (15x15).