Your suggestions would be greatly appreciated

Lipper,

Connect the front left and right rca outputs of your processor to the 'surround' left and right rca inputs on your new tube preamp with ht pass thru. There will be a 'ht passthru' switch on the front of the preamp. When this switch is engaged, it will play your front left and right main surround channels from your processor. When it's not engaged, the preamp will play whatever the input selector knob/control is set to.

Let us know if you use a subwoofer for both 2-channel and home theater. If you do, I'll need to give you further setup instructions for this to work properly.
Also, you need to make sure that the 'input impedance' of your power amp is about 10 times greater than the 'output impedance' of the tube preamp you choose. This ensures your amp has enough voltage gain to do its job. If you let us know the make and model of your amp, we can let you know what output impedance to look for in your new (or used) preamp.

I think you made the right decision. I was stuggling with this, too, until I employed this solution. It has been working very well.
Hope this helped,
Tim

Tim - thank you so much for your assistance - incredibly helpful I assure you!!

I do use my powered sub for home theater and 2 channel. As previously stated, in order to use it now for 2 channel listening I must set the Oppo speaker configuration in the player to small for the 2 main channels. This to me is ridiculous as my Reimer Tetons can reach as 14 Hz. I use the sub as my room is large and sometimes can use the low end push to suit my tastes. Especially when the sub is not boomy at all.

The Adcom amps are a 2 channel 5500 and a 3 channel 5503 modified by Stan Warren back in the day ('90s).

Again, my sincere gratitude for your help. Suggestions on which tube pre and processor to look at? Looking at around $5000 for both and would be buying here at Audiogon. Keep in mind that I would want the sub to be able to be utilized all the time including in 2 channel direct pass.

Thank you all!!

Lipper

Lipper,

The Adcom 5300 has an input impedance of 49,900 ohms. So, you need to look for a tube preamp with an output impedance of 4,900 ohms or less.

For the subwoofer connection, you'll need an rca y-adapter (2 female rca connectors feeding to one female rca connector). Run a single male-to-male rca cable from the subwoofer/LFE output on your processor to one of the female rca inputs on the y-adapter(the side of the y-adapter with dual female connections). Run another single male-to-male rca cable from the extra audio out on your tube preamp to the other female rca connection on the y-adapter(the side of the y-adapter with dual female connections). Lastly. run a singl male-to-male rca cable from the single female rca side of the y-adapter to the rca input on your subwoofer.
This set-up will feed the sub/LFE signal to your sub when using your processor for ht and it will send the signal from your new preamp to your sub when listening to 2-channel music through the preamp. You may need to adjust the sub's high pass filter to find a 'happy medium' cutoff frequency that works well for both ht and music. Or, you could change the sub cutoff frequency depending upon which you're listening to. I usually set my sub to about 35hz, which works well for music and ht for me. Since your left and right front channel speakers are very low frequency capable, you may also want to set your laft and right mains to 'large' on your processor settings to direct the full frequency range to your front speakers. 'Large' is the setting on my Parasound processor that sends a full range signal but your Audio Refinement Pre2 DSP may be called something else.

To summarize, I think a tube preamp with 'ht passthru', with an output impedance of 4,900 ohms or less and with an extra audio output for your sub should be a very good fit for your system. I know that the tube preamp I use (VTL 2.5tl) does meet all these criteria. However, I think there are probably several others that would work just as well and would sound as good or possibly better. I'd suggest seeing if a local dealer would let you try a couple out in your system.

I'm not exactly sure why you want to buy a new processor since the one you have is a very nice unit. The only reasons I can think of are either you don't like the sound of yours or you want to use one of the newer codecs.

But, if you have extra funds burning a hole in your pocket, I would suggest you consider replacing your Adcom amps with some newer class D ones (Wyred4 Sound, D-sonic, ClassD Audio, Channel Island Audio, etc.) This would give you a bigger bang for your buck, sound quality wise, as long as you're satisfied with your current surround sound capabilities.

If you're set on a new processor, You may want to check out the new Emotiva processor that has gotten very good reviews.

Good luck,
Tim

Lipper,

Just realized I listed your amp as an Adcom 5300 when it's actually a 5500. Sorry, but the good news is that both have the same input impedance: 49,900 ohms.

Thanks,
Tim

I agree that the VTL 2.5 that Noble100 recommends and owns is an excellent choice. Its very underrated.