Bought an Audio Research Amp


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

 

Pre: ARC LS25 MKII

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

@riaa_award_collectors_on_facebook 

Any idea which parts are considered unobtanium, and how prone they are to failure? Or any sort of preventative maintenance that could extend the life of my amp?

@ghdprentice 

Thanks, that is indeed informative. Some recent reading indicated that the Concertino is well suited to a smaller room. In any case, it looks like my option is try a bunch of speakers til I find what I’m looking for, which means judicious spending on the pre-owned market, so I don’t get killed on depreciation in the event of a necessary resale. Guess I’ll have my work cut out for me.

Post removed 

OP,

Yes… excellent. That is correct, listen to a bunch of speakers. For me, I went listening to lots of different speakers… then one grabbed me…. emotionally. This was my first set of high end speakers… I was listening to them… they brought tears to my eyes… I bought them. They had AMT (Air Motion Transducers) for the treble and midrange. They got that right..

 

Your speakers need to connect with you emotionally. It is good to be an analytical… for a while when auditioning speakers. But after you get that unnecessary part out of the way… stop listening to the speakers and listen to the music… when the music becomes compelling… you establish an emotional connection… buy those.

@rfnoise 

I did the mod my self , needed to change the voltage regulators for the heaters to higher ampere .

as for rolling 6h30 tubes, you could try 6n6p . It's a drop in replacement but with lower current draw .

@rfnoise I have been in love with ARC for abut 4.5 years now.  I took a long journey from an LS3B with the Classic 120 mono blocks and a PH5 phono stage to get to the previous generation of their REF lineup.  I tried out several different line stages and phono stages along the way, but my amp experience was limited to the GSi75 integrated, REF 150 and now the REF75SE.  I had one quick opportunity to hear a D200 that I had purchased for a friend in person and had set up before shipping.  It was a very strong amp and definitely was superior to my backup amp, a B&K REF 200.2 S2.  When the time is right, I would encourage you to try one of their tube amps.  All 4 I have auditioned sounded amazing.  I still have the Classic 120s which I have compared to all the others and still put up a good fight against them all.  I was just ready to move on from that look and the space they took.  I always loved the silver REF look and am quite happy and fortunate to have that lineup now.  FYI, this is straight off the ARC website regarding their limited service. You can find it in their FAQs, models no longer serviceable.

The Audio Research products listed below are NOT serviceable because parts are no longer available.
• Some D-Series amplifiers
o D52/B
o D60
o D100/A/B
o D110/B
o D111
o D120
o D130
o D240
o D350/B
o D400
• HD220
• SD135
• CD2
o SP4
o SP5
o SP7
o 150.2
o 300.2
o 150M