McCormack Advanced Rectifer Circuitry

I'm on the list to have my DNA-125 Platinum upgraded with the new ARC (both 1 and 2.) :D

Has anyone here already had this done to their McCormack amp? If so, what's your impression?

The more I read and think about this upgrade, the less I think about spending money on other things. So thanks in advance for saving me money in a bizarre sort of way!

Can you provide any more info about this? Now's the first I've heard of it, and the SMc website's link for it is inactive at this time. (Same for the DNA-500 mods -- the link placeholder's been there for a while, but is still not active.)
I am also curious about the ARC upgrades, but for the DNA-0.5 or DNA-1.0.

Here are the details I received in an email from Kris at SMCaudio about upgrading a DNA-0.5. Not sure if the ARC-1 and ARC-2 are included in the price of the DNA-125 Platinum upgrade.

The ARC-2 replaces the original IXYS soft recovery diode option on the outputs. Cost is $500.00 and is available on all McCormack amps except the HT-1 & HT-3.

The ARC-1 is a variation of the ARC-2, but is installed on the main AC power supply. Cost is $285 and is available only on the DNA-125 and DNA-225.
When yours is scheduled?
My DNA-125 at SMC shop right now for a Platinum + ARC2.
I'll let you know when I get it back (4-5 weeks).
BTW, I've heard DNA-225 with ARC2. Although it still has less than 100 hours brake-in time, it's really something, but I'll let the owner of DNA-225 speak for his amp.
It's hard for me to tell what impact the ARC2 mod had on the performance of my amp, since I had everything done at the same time. I had it scheduled for Gold originally, but while the amp was there I figured I'd do couple more things. I talked to Kris and Steve about getting a Plitron, but Steve suggested that I try the ARC2 instead, since the DNA-225 already has enough power to drive my(or pretty much any) set of speakers.
Although the amp is not fully broken in yet(less than 100 hours playing time), as Nyran94 noted above, it is sounding very good. Way better than stock. And it seems to get better as it plays more, so.....
I wish I could be more helpful with opinions just about the ARC upgrade, but, don't know.

You tell us when you get it back!!! :)

Kris anticipated mid to late September, although it could get pushed back depending on how long the current jobs take.

Kris did say the ARC-2 was a more significant upgrade than the ARC-1, but I figured I'd avoid future shipping and labor costs by having both done at the same time.
Where can I read about this upgrade, as you say you've done? Do you mean in the AG forums? Thanks
Zaikesman, the best way to find out is to ask Steve.
Call or e-mail him, so you get a written response. This way you can read it over and over again, until curiousity takes over and you send your amp in for this
LOL, Aud!! :D
Hey, my amp is getting better and better......

Howard, I changed the AC Mains fuse in my amp to Hi-Fi Tuning fuse. Very nice tweak!!! Definitely worth the $25(despite that it sounds crazy to pay this much for a fuse).

I want to try these fuses in my CD player next.

Zaikesman, I still haven't opened my ARC CD3MkII to see if there are fuses, but I plan on doing it this weekend.
Hi Guys -

As has been pointed-out by several posters, I am woefully behind in updating the information on my website. I do apologize for that, but will plead extenuating circumstances - I've got way too much work to do! Anyway, I promise I will try to get the website more up-to-date soon, and in the meantime you are welcome to call with your questions.

The "ARC" (Advanced Rectification Circuit) upgrade is a fairly new option, as I just finished the development early in the year. I don't want to give away too much , but it is a new approach to doing the DC smoothing following rectification (or a new twist on an old idea). It makes a very nice improvement in overall performance, PRAT, and individualization through the midbass and lower midrange. There are 2 variations: ARC-1 and ARC-2 (used at different points in the power supply system). The ARC-2 can be installed in any of the amps I currently upgrade, and the ARC-1 is applicable to the DNA-125 & 225 only. Cost (as part of an upgrade) is $250 for the ARC-1 and $500 for the ARC-2.

And finally, since Zaikesman asked about the DNA-500, I have (reluctantly) decided to drop this one from the upgrade list. It is simply too costly in terms of time, and I have been devoting most of my time (what little I've got left!) to finishing my new preamplifier (and it's getting close!).

Call me if you've got questions.

Best regards,

Steve McCormack

I remember reading here a couple years ago that folks were anticipating your new preamp design - can't wait to hear how it turns out!
Anybody with updates to report on this topic? I recently purchased a pair of used DNA-125 Platinum Monos and should receive them tomorrow. These were modified close to three years ago, so they predated the ARC options. Before deciding whether to send them back to SMC for any further work, I'll be comparing them against my stock DNA-500, which should prove interesting. (I also used to own a stock 125 stereo, which I compared against the 500 too, so I'm familiar with the sound of the starting point in this face-off. In that case, unsurprisingly, there was no comparison.)
Had the ARC-2 upgrade done to my Platinum DNA225 this past summer. Most noticeable effect has been additional clarity and information in the top end. Hope this helps.