Audio Research Reference 5SE reliability

I drive my MC601s with the 5SE, no problems. The 601s are 20K and I believe the 452 is as well. I have always been an ARC tube amp customer, but I was so impressed with the 601s I traded in my VT200 for them. Never been a Mac fan or a "hater", but these are really very fine amplifiers.

Djcxxx, your MC601's input impedance of 20K ohms is the maximum load recommended by ARC. If you are running anything else off the other Ref 5 outputs (e.g., a sub woofer), the combined impedance load that the Ref 5 sees will likely drop below 20K ohms. It might be worthwhile to have a call with Kal at ARC to learn if he thinks the 20K ohm load is ok.

Bifwynee, my Ref 5SE output goes to Bryston 10B-SUB, then to McIntosh MC452 (driving Focal Utopia 3 Diablo) and JL Audio Fathom f113.

I contacted Ron C of McIntosh through email and he confirmed ARC preamps work well with McIntosh amps. But no success contacting ARC technical support yet due to time zone (I am in Malaysia) as no ARC email contact is available.

After adding the Cooler Master 12V PC chassis fans (1200rpm and they are really quiet) at the left side of Ref 5SE, no more over heating issue.

Anwar, check the input impedance of your sub. I suspect that the combined impedance load on your Ref 5 SE is less than 20K ohms. If so, you are overloading the Ref 5 and potentially degrading its already excelleant performance. Try Kal again. If you can't reach him, try Chris Ossanna.

Remember, the formula for combined impedance is:

CI= (Input device 1 - ohms x Input device 2 - ohms)/(Input device 1 - ohms + Input device 2 - ohms). So, if you do the math, if both devices have an input impedance of 20K ohms, combined impedance is 10K ohms . . . oopps.

Btw, are you symetrically loading the Ref 5's Main 1 and Main 2 outputs? That is are both Mains balanced or SE, or are you asymetrically mixing and matching the Mains: one balanced and the other SE. If the later, not a good thing to do.

That's why I worked with Tom Tutay in Florida. A great guy and very well respected in the audio hobby. If you do have an issue, check my threads for his number.

Good luck and let us know how you make out.

Bruce

To add my 2c to Bifwynne's post and unless JL Audio has changed it, the JL Audio subwoofers impedance is an extremely low 1k Ohms.