New (to me) amp: McCormack DNA-125

Clipdat

My new amplifier arrived earlier this week so I figured I would take some unboxing photos! Looks to be in very good condition! Rubber feet have gotten sticky over the years and appeared to have some schmutz stuck to them. Inside looks clean with minimal dust, caps look good and don't appear to be bulging or leaking.

It shipped double boxed and with large foam pieces. Very messy with the little bits everywhere that I had to vaccum up but well protected in transit! It came with the original manual and power cord (beefy 14awg) as well as the original invoice which I thought was interesting.

Have not hooked it up yet, but I will keep updating this thread as I get my ears on it and share my impressions.

F1nut

Sweeeeeeet

hochpt21

Beautiful

halo

Gorgeous amp Drew! Nice score!

Nightfall

F1nut wrote: »

Sweeeeeeet

You licked that amp?

lightman1

Skeet!

F1nut

Nightfall wrote: »

F1nut wrote: »

Sweeeeeeet

You licked that amp?

No, i rubbed my dingus on it.

Clipdat

It must be some kind of Club Polk record, 4 posts before the thread derailed and turned phallic?

Viking64

And "skeet" was ejaculative.

Nightfall

Clipdat wrote: »

It must be some kind of Club Polk record, 4 posts before the thread derailed and turned phallic?

ding·us
ˈdiNGɡəs/
nounNorth AmericanSouth Africaninformal
noun: dingus; plural noun: dinguses; noun: dinges; plural noun: dingeses

used to refer to something whose name the speaker cannot remember, is unsure of, or is humorously or euphemistically omitting.
"here's a doohickey—and there's the dingus"

Bold the text in question. Technically it could mean anything, he just can't remember the name of it.

MrBuhl

Congrats man! Better get the sack guard ready - don't want them getting blown clear off!

Viking64

Nightfall wrote: »

Technically it could mean anything, he just can't remember the name of it.

Frank Sinatra didn't remember to wash his dingus.

daddyjt

Congrats - I picked up a DNA225 to try out several months ago, and it hasn’t left my system yet.

Enjoy!

tonyb

Haven't hooked it up yet ?? Lets go brotha....giddy-up, let that baby break in a bit and give us your impressions.

gmcman

Very nice. Enjoy.

Just added a DNA-1 myself and I'm enjoying it immensly.

tonyb

I also might mention, Steve McCormack himself has said his amps respond very well to upgraded power cords. Something all you owners should consider at some point.

Clipdat

I finally got everything hooked up, boy was that a royal pain in the @ss that I will spare you the details of. Let's just say that I'm going to be sore tomorrow. Look how little clearance there is between my lame MDF "rack" and the heatsink fins. Also yes I know you shouldn't stack components, but I had to stack the CD players to make this work. Yes I'm a weirdo who has three CD player sources.

Anyway. in an effort to not change out too many components at once, I decided to use my Tascam XS-8 DJ mixer/preamp instead of the Schiit Saga for right now. I already am very familiar with the sonic signature of this piece of equipment, so I know it doesn't really color the sound at all. It's an all analog design, no DSP or other digital circuitry to muck up the sound.

Tried it out with a few CDs via the Marantz and at lower/moderate listening levels, I'm not noticing a whole ton of difference versus the NAD C 316BEE integrated that I just had hooked up previously. It sounds very similar, with perhaps a slightly more defined and cohesive stereo image.

It's possible that it's going to need several hours of run in time to really settle in. If you look back at the photos I posted, the original power cord is still in it's factory coil. Either the original owner used an aftermarket cable or this amp has barley ever been used period. If that is the case, then we're probably looking at 50+ hours before this thing is performing up to it's potential.

Clipdat

Oh, a few quirks that I forgot to mention in my post.

It makes a thump sound through the speakers when you turn it on, and also slightly dims the lights.

Also, if you put your ear up to the tweeter with no signal, you can hear a very slight hum/buzz.

Also if you kneel down next to the amp itself you can hear a slight hum/buzz, presumably coming from it's power transformer.

The NAD integrated was literally silent, FWIW - from both the speakers and the unit itself.

Not showstoppers by any means since when music is playing you can't hear it. Just figured I'd mention it.

tonyb

Sounds more like a ground loop issue, or bad cable in the mix.

gmcman

I don't know if the CD6004 has variable volume output through the analog, but was thinking you could bypass the preamp and re-evaluate.

I would start removing components until the noise has been isolated.

I'm going to go out on a limb here....i haven't heard that XS8, but I wanna say it's a safe bet the XS8 is going to change the sonic signature of the DNA in a big way, which is why you feel the Integrated is similar.

11tsteve

There should be no noise. Also, my DNA .5 had a very soft thump, but the dimming of lights would concern me. Do they stay dimmed?

pitdogg2

Chances are the lights are on the same circuit. The in rush of current could make the lights dim if that was the case. The tweeter buzz/hum is not uncommon in many amps. If you must get right up on it the hear it it's a non issue. If you can be in the seated position and it is noticeable that could another story.

11tsteve

my point is the amp current should not be enough to dim lights unless the circuit is not a good one. Then the amp should not be on that circuit.
The amp draws about the same as a 75W light bulb at idle. Even on power up, it should not be enough to dim lights on a healthy circuit.

Nightfall

Why is the mixer in there?

Clipdat

The sound through the speakers is nowhere near the traditional "60hz hum" ground loop sound. I've dealt with this before on my PC audio setup, so I am familiar with it. It's just the faintest background hum sound, heard along with the slight white noise "hiss" that you hear when you put your ear directly next to the tweeter. It's a non-issue in the sense that it cannot be heard when music is playing.

I only mentioned it because it was something technically different than I had with the NAD, which was 100% black, no hiss, no noise coming through the speaker at all.

The faint (transformer?) hum coming from the unit itself is a separate quirk. It can be heard as you get within a few feet of the amp. Again, it doesn't seem like a showstopper in the sense that you can't really hear it while music is playing and you're in the listening position.

tonyb wrote: »

Sounds more like a ground loop issue, or bad cable in the mix.

gmcman wrote: »

I would start removing components until the noise has been isolated.

pitdogg2 wrote: »

The tweeter buzz/hum is not uncommon in many amps. If you must get right up on it the hear it it's a non issue. If you can be in the seated position and it is noticeable that could another story.

The lights just dim slightly in the half second or so while you turn the power switch to the on position and the the speakers make a thump sound. They doesn't stay dimmed. I believe it's like you described, just the sudden rush of current that it's demanding at startup.

I would not be surprised at all if the circuit was not "healthy", as this house/apartment was built in 1904, and it's a rental.

11tsteve wrote: »

There should be no noise. Also, my DNA .5 had a very soft thump, but the dimming of lights would concern me. Do they stay dimmed?

pitdogg2 wrote: »

Chances are the lights are on the same circuit. The in rush of current could make the lights dim if that was the case.

11tsteve wrote: »

my point is the amp current should not be enough to dim lights unless the circuit is not a good one. Then the amp should not be on that circuit.
The amp draws about the same as a 75W light bulb at idle. Even on power up, it should not be enough to dim lights on a healthy circuit.

The CD6004 only has a fixed output, not variable.

Regarding the Tascam, do you mean that it's build quality would be equivalent to the preamp section in the NAD, which is why I'm not noticing a sonic difference?

I'm not saying it's impossible, but I don't see how this particular mixer/preamp could be changing the sonic character of the amplifier in a "big way". This is an all analog solid state design that should not be influencing the sound that's passing through it.

The specs are respectable, in my opinion:

THD LINE/CD <0.08%
Signal to noise Ratio LINE/CD >95dBV

I have the Schiit Saga ready to put into the mix, but I was trying to fairly evaluate the sound signature of the amplifier itself before adding/changing too many components.

I listened to music through the system today for a about 8 hours and honestly it sounds very very similar to the NAD. I was just expecting there to be a dramatic difference, and I'm not hearing it.

Don't get me wrong, it sounds good (so did the NAD), and I have no complaints at all. Just was expecting a clearly audible difference when moving to an amplifier of this caliber.

gmcman wrote: »

I don't know if the CD6004 has variable volume output through the analog, but was thinking you could bypass the preamp and re-evaluate.

I'm going to go out on a limb here....i haven't heard that XS8, but I wanna say it's a safe bet the XS8 is going to change the sonic signature of the DNA in a big way, which is why you feel the Integrated is similar.

Quoting the OP for you:

Clipdat wrote: »

Anyway. in an effort to not change out too many components at once, I decided to use my Tascam XS-8 DJ mixer/preamp instead of the Schiit Saga for right now. I already am very familiar with the sonic signature of this piece of equipment, so I know it doesn't really color the sound at all. It's an all analog design, no DSP or other digital circuitry to muck up the sound.

Nightfall wrote: »

Why is the mixer in there?

11tsteve

Different ears, I suppose. I went from a Conrad-Johnson to my McCormack, and the difference was noticeable, much more so after I had the upgrades done.
And even before the upgrades, it was a dead quiet amp.
I have an NAD 2150 I just had rebuilt with that transformer hum, and frankly it drives me nuts. The tech insists he didn't hear it when he had the amp. I would like to know what the issue is and how to fix it.

gmcman

Clipdat wrote: »

Regarding the Tascam, do you mean that it's build quality would be equivalent to the preamp section in the NAD, which is why I'm not noticing a sonic difference?

I don't know anything about the build quality of the Tascam. I have to assume for the sake of this discussion, that a DJ mixer is not a fair comparison to a NAD integrated preamp.

Clipdat wrote: »

I'm not saying it's impossible, but I don't see how this particular mixer/preamp could be changing the sonic character of the amplifier in a "big way". This is an all analog solid state design that should not be influencing the sound that's passing through it

In theory, I see your point. But again, for the sake of this discussion, just because it's an "all analog" design...that doesn't necessarily mean it's doing the best job of trying to maintain sonic purity as it passes through it.

I personally don't feel that taking the clean sound from your Marantz, through a DJ mixer is going to aid you in assessing the SQ of your McCormack amp.

tonyb

Agreed ^^^

From what I can tell, is that somewhere in your system is a bottleneck. The Nad and the McCormack are two different sounds. If you can't hear a difference, something in the mix is holding things up.

That can be a variety of things. You could have an impedance mismatch going on, a poor quality cable in the mix. That DJ mixer certainly isn't helpful.

Regarding the noise issue, something isn't right if the amp has a hum to it. These amps run quiet, and don't produce transformer hum or hiss in the tweeters. Either something is screwy with the circuit it's plugged into, or the amp itself.

A good non current limiting power conditioner could help as your in an apartment and limited to what you can do. You could also change the wall socket to a hospital grade at least, if that's possible.

kharp1

I tend to agree with Tony here, there is considerable difference between the NAD sound and McCormack. No offense to anyone, but, sone people don't hear differences and you may be one of those people. I wish I was at times.

I had a DNA-125 until recently and it's still in the Polk family. It had been modded with some cap upgrades and I experienced none of the issues you described. There is a possibility it could need some maintenance.

As for the Tascam and specs...specs aren't all they're cracked up to be. An all analog design can still use inferior quality components and thereby degrade a signal. Not all resistors and capacitors are the same. A $500 Dueland won't sound like a $10 capacitor.

Hum could be related to a couple of things...transformer going bad, though I doubt it. I think, THINK, the McCormack uses a pretty good torroid, so I'd start looking elsewhere first, like grounding issues. Take the ground lug off the amp cord first and see if that eliminates all, or part, of the hum.

I'd just leave the McCormack on all the time, it'll draw practically nothing while idle and won't build up heat.

MrBuhl

Have to agree with others here, I have two McCormack's (one is 11Steve's formerly) and both are silent running - so that's very curious to me. I did have to do some swapping to eliminate a ground hum at one point, but I'm inclined to think something else is going on here unfortunately. It (the McCormack sound) was a very noticeable difference from my Audire, B&K, and Harman Kardon, though, I have never compared directly to an NAD so YMMV.

tonyb

Where did you buy the amp from ?