Bought an Audio Research Amp

I feel like i should preface this with a basic rundown of my system up til now:



Amp: Legacy High Current Amplifier (rebadged CODA Stage 3.2)

Dac: SMSL M400

Transports: Auralic Aries Femto/Sony DVP-S7000

Speakers: LSA-10 Signature

Subwoofer: Recapped Velodyne Servo-1200


Anyhow, as the story goes, I recently acquired an old Yamaha RX-770 on the cheap, figured maybe I’d gift it to a friend. When I inserted it into my system to test it, I was shocked by how good it sounded. It sounded really close to my separates. Worse yet, the Yamaha actually made much better bass through my speakers (sub was off). It was louder, faster, and better controlled sounding. This was extremely distressing. 

I thought maybe this was due to the age of my CODA, but the yamaha is actually about ten years older, so that didn’t make sense. The best I could come up with was just a poor match for my preamp. I can’t recall the figures off the top of my head, but i did some math when I bought the amp to ascertain if matching them was appropriate, in terms of both input sensitivity and impedance, and recall that both were  toward the bare minimum.

Having read numerous times that the increase in synergy is substantial between ARC components, I started casually shopping online for an ARC amp. I briefly entertained a VT100 MKIII which seemed a good deal, but the price of retubing it currently is around $1000, and i just don’t think right now is the time for me to jump into tube amplification with the soaring prices of tubes.

A 300.2 caught my eye, but I couldn’t find any information online that convinced me that a Tripath class-d design of ten years ago would better a solid class a/b design, and I can’t really afford to buy an amp just to find out.

Fortunately, I came across a craigslist ad a week ago for a D400 located only an hour away from me, at a price that was a fair bit lower than similar models had sold for recently (as per Hifishark). Awesome. 

I spoke with the gentleman who had listed the amp, and it turned out that he was the proprietor of a stereo service center, and was selling it for a longtime customer who had been using it, along with 2 D200’s and a D300, to power an eloborate horn speaker setup, but who had, due to the onset of Alzheimer’s, become unable to manage the complexity of his own system. This is, I have to say, extremely tragic. The store’s owner told me the amp was in great shape, had been well cared for, and due to being used in a high efficiency setup, had never been run hard.

Needless to say I was extremely excited at the prospect of owning a D400. Wasn’t able to uncover much in the way of reviews, but I was able to find that it shared circuit-design lineage with the extremely well-regarded d240 MKII, as well as reports from other users who’d paired it with an LS25 and reported extremely positive results.

So I made an appointment to bring my preamp down and auidition the amp. When I arrived, the store owner was extremely friendly, more than happy to take the time to talk audio with me,  show me his personal system (Threshold/Altec VoTT), and all the amazing gear he had on hand, even though I showed up shortly before his usual closing time. 

And the Amp? I really wasn’t prepared for how colossally huge it was… it really is a monolith, just beastly.As far as the sound goes, well, let’s just say that by the time I’d been listening to it for 5m, I already knew i was going to buy it!

Once i got it home (nearly destroyed my back getting it out of the trunk), and into my system, it sounded even better! Compared to the CODA, highs were more sharply focused, I gained more of a sense of instruments existing in specific “space”, and the bass/mid bass had tightened up considerably while also increasing considerably in terms of volume and impact. Overall, I’d say the sound is   less on the warm side than the CODA, which I think is better for my speakers  which have a pretty laid back character.

I will, say that the amp runs pretty hot, even at Idle. I don’t know if it’s biased pretty hard into class a, or what. Also, it does does take 2-3 hours of warm up before it sounds at it’s best. I’ve taken to power it up the night before if I’m intending to do a lot of listening the following day.

Really, I couldn’t be more ecstatic; I really feel like I took a big step toward being  “there” with my system. Of course that just leads me to thinking about what I need to start agonizing over upgrading next, ha ha!

Big shout out to Kevin at The Stereo Workshop in Eugene, OR for being such a gracious host and giving me such a fair shake.


@rfnoise -At 200W a channel, you have A LOT of choices. Given your tastes in music I would agree with the poster who said Sonus Faber. I'd also add Totem and the Spendor A or D series. Each speaker has terrific PRaT which is something your ARC combo excels at.

Let us know what you decide upon. It's always fun participating in these threads.

PS-Ignore people telling you that if your equipment breaks, you will have difficulty getting it repaired. There are many options for ARC repair services, IF you need them.

Happy listening!



I’m finding that I tend to prefer a more cool/neutral sound; whatt I’ve read about the Sonus Faber sound tends to use words like “warm” “dark”and “lush”.  Has that been your experience? 


Well that’s disconcerting… it was my understanding that ARC stands behind their heritage products regardless of age. I mentioned that the person who brokered the sale was a tech; he said that when his customer brought it in he opened it up for a bench test, and everything checked out within spec, so hopefully I won’t be ending up with a boat anchor anytime soon. I did ask him if I should be worried about the age of the electrolytics in the amp, and he told me that the “full recap craze” (his words) was a fairly recent development, and that he didn’t believe in replacing something unless it was failing/out of spec. 

It’s interesting that there isn’t a solid state amp in their current lineup. Correct me if I’m wrong, but as far as I was able to ascertain, their last solid state power amps were the DS series, which was over ten years ago.

I have an arc pre I love. I don’t think I’m getting enough transparency of instrumentation from my Pass Labs 25 watts per channel. Would the D400MKll be the answer? It’s easily available at good prices. I have always read as well arc works best with arc and I can't afford the new tube models and worry about used tube units. Would any other Arc solid states be another option?

Me too fell in the audio research trap 3 years ago,  there's no coming back..

After some mods I now have 6n1p on input and 6n6p out in my ls25 mk1 ..

Some day I might have the means to get my self the ear 912 pre , and that may be the end but for now I would not change s thing 

Cheers to a great pre 😁


As a real rookie in this stuff, I don’t really feel qualified to offer advice. At the risk of making an absolute fool of myself, I’ll conjecture that it’s a vague possibility that your Pass Labs may share some distant design lineage with my CODA, as it was built by ex-Threshold alumni. As I stated above, the gains I’ve made by moving to the D400 have been phenomenal. As far as my research has been able to ascertain, in terms of solid state, the D240, 100.2, and D400 are the amps to look at from ARC. I went with the D400 BC even though it’s probably overkill for my current speakers, I find a certain security in having an amp that could handle any speaker I might throw at it down the line.



who did the mods on your pre? Mine is the MKii, with 2 6h30’s, so no tube rolling for me.