Red Dragon's new S500 Class D Amp

I purchased an S500 a few weeks ago, but haven't put too many miles on it yet. I am building a second system (music only, 2ch) that isn't ready yet, but I inserted the S500 into my main HT/music hybrid system for a couple of weeks of music listening.

Here are the associated components:
Primare SP31.7 processor (in analog "bypass" mode)
Yamaha CDR-HD1300 (a very early hard disk based music server, used as a transport)
Wyred-4-Sound DAC2
Totem Mite-T loudspeakers

The Red Dragon S500 temporarily replaced a Sherbourn 5/1500A (5 Class A/B monoblocks in a single chassis design). I think the S500 sounds great. It is dynamic, very quiet, and a remarkably wide soundstage. A common criticism of Class-D amps, particularly earlier ones, is that they are bright and "brittle" but the S500 is neither of these things. Compared to the Sherbourn, it is quicker and more musical, but a little less "authoritative" sounding (the Sherbourn is a bit dark). I think the S500 is a more neutral amp than the Sherbourn. The lower gain (26db vs about 30db for the Sherbourn) meant my pre/pro had to work a bit harder. It runs very cool, something I was looking for since my 2nd system's room will not tolerate a Class A/AB space heater, and it amazes me that such a small amp could produce so much clean power and sound so good doing so. Overall I am very impressed with the S500 so far.

-Dean

I haven't heard the PASCAL amp module making class D power but I have never loved the sound of the usual class D suspects. I have to say this one looks intriguing and I like it when an amp doubles down into 4 Ohm (like good ole class A). The 12Lb heft also ads credibility. The one reviewer didn't exactly go overboard with compliments, so we will have to see if the small size amp big power output is a winner or just another almost. Class D does do a great job with power hungry subs, again, lets see if it can go up the sound spectrum.
It is going to take an awful lot to take tube amps from me so perhaps I am not the best judge.

OR if the amps are compatible I would bi-amp them horizontally, but the gain of the Adcom is 27dB while the gain of the S500 is 26dB. Also, S500 has higher output at 4ohms and 2ohms than the Adcom....

The 1dB difference in gain might not be an issue at all. It's a difference no doubt but it might not show up in the playback. You could use the S500 to drive the highs & mid & your Adcom to drive the bass since the Adcom has a heftier sound.

Your comment of "Also, S500 has higher output at 4ohms and 2ohms than the Adcom" has me confused.
You realize that's not the output impedance of the S500 amp? It's the ability of the amp to drive an 8ohm & 4ohm speaker load with a minimum speaker load of 2 ohms. You might already know this & just mis-wrote the above line but i thought I'd clarify. Thanks.

Since my last post on this I acquired a pair of Infinity Kappa 9's. The Kappa 9's require lots of current from amps capable of delivering high current into very low impedance as it has an impedance curve that drops below 1 ohms resistance at two frequencies and stays near or below 3 ohms much of the curve.

My Kappa 8's also are low impedance speakers but not as hard to drive as the K9's. My Adcom does an ok job with the K8's but the K9's are too much speaker for it alone. Both speakers are reported to do much better bi-amped and this is my eventual target configuration for both.

At some point I will purchase a high current class A amp for the K9’s to use bi-amped on the high end. The S500 may fit into this plan as I could use it on the low end bi-amped on either the k8 or k9, which ever sounds best. Or the Adcom’s on the low end and s500 up top. I plan on keeping both K8's and K9's long term.

The S500 is rated at 250w/8ohms, 500w/4ohms, 750w/2.7ohms and is reported as "stable" at 2ohms. Those are specs you normally don't see unless you are looking at a Class A amp. But specs are one thing and real life sound is another.

My AdCom is rated at 250w/8ohms, 350w/4ohms with no measurements reported below 4ohms.

I know you are probably thinking “why doesn’t this guy just order an S500 and try it for the 45 day trail” and that is what I will likely do but I don’t take returning amps lightly and wanted to hear some feedback if my direction / plans seem sound?

1extreme

"I know you are probably thinking “why doesn’t this guy just order an S500 and try it for the 45 day trail” and that is what I will likely do but I don’t take returning amps lightly and wanted to hear some feedback if my direction / plans seem sound?"

I commend you on doing your homework first and respecting the manufacturer's needs as well as your own. Good luck.