Mac 402 & Audio Research LS25MKl ?

Seems to me that you have a heck of a good system. you didn,t described your room or your room treatment. But having that nice pieces of gear and not having attention as to the best in room acoustics would be a waste. I would have an acoustical expert or company like rives take a look at what can be done. BTW; While I have heard at a friends system the ls25 mk2 and its a very good sounding pre its disadvantage its that you are stock with the 6h30 tubes and no 6922 tube rolling if you go into that direction. Good luck on your descicion.

only thing i can suggest send your ls25 to ARC have it upgraded to mkII ..you will notice an improvement ,your mac 402 is a top notch amp ..

Chiming in a little late here, but, I second Gmorris as I'm running the same tubes in my LS25 MKI, much better than the stock Sovteks. Other than the type 2 EH tubes from upscale, I haven't rolled any others. I don't know anything about the MAC 402, but if it's a truly balanced amp and your not using XLR cables between pre and amp, you should try it. Switching my system from SE to XLR, specifically between pre and my amps (JC1's) catapulted my system to another level entirely.

I am using the 6H23 NOS Type 2 from Upscale Audio in my LS25 MKI with excellent results.

Make sure your system isn't "new to you" before you go changing things. It will make your future changes a lot more sensible.

Hey Dave, The cables you've mentioned are fine! I also feel that prior to any other changes, Tube Rolling may be the next place to begin experimenting with your new pre. Maybe some other fellow Audio Research LS25MKl users will come to your aid in sharing some of their tube rolling discoveries?

I just sold my A.R.LS25 great preamp, may I suggest tube rolling. Your mac is fine. Other suggestions are good balanced cables.

I believe your going to have to spend a whole lot more to improve the Mac 402 - I would give your current system plenty of time to settle in, really get to know it and then work on a change if you want something different - just my opinion.

Cmo,
I have the MBL 1531 CD Player. I also use the Reimyo ALS-777 AC Line Power Conditioner. All my power cords, Interconnects and speaker cables are Harmonix.
I do plan on adding Analog in the very near future.
I have 2 dedicated lines and a dedicated room approx. 24 foot x 30 foot with a drop ceiling.
Thanks,
Dave

If you have a good amp, preamp, and speakers (and you do), the next place to look at is your front end......... what's going on there. More info..........