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[BobM]

I will also throw my modded McCormack DNA .5 "near-Rev A" (which is now called the "Gold" package) SS amp onto the list to see if I can generate any interest.

This amp started it's life as a DNA .5 deluxe, and has had most of the upgrades standard in the McCormack "Silver" upgrade and a significant number of the "Gold" mods as well:

- SMc circuit revision with high performance NP Muse Capacitors
- standard upgrade of the driver board
- standard upgrade of the output boards (includes wiring and a select group of high performance components)
- Cardas RCA jacks GRFA
- Cardas Binding Posts, model CCGR-S or CCBP-S
- Soft Recover Diode Bridge Package
- Rebiasing (per Steve's express instructions)
- Full upgrade of the output board components to Nichicon Gold caps, with KZ and Relcap bypass

The amp was voiced with the help of Bob Crump (God rest his soul), who also voiced the Parasound JC-1 amp for John Curl. The Nichicon Gold caps are used throughout both the DNA .5 and the JC-1. Bob Crump used RelCap RT caps and Nichicon KZ caps as bypasses on the JC-1 instead of BlackGates, because of the propensity of BlackGates to lose their forming/break-in if not constantly played. I also followed Bob's voicing trick to good effect on this amp.

It is smooth and extended with a wonderful presence, free of grit and grain. It gets to the soul of the music. 100W into 8 ohms, 200 into 4 ohms and 500 into 2 ohms - this amp can drive most speaker loads with sufficient power and finesse.

Many ravers have heard this amp in my system and can give you their impression as well. I'm parting with this because I upgraded to the DNA 500, and I have to say that the family sound is very much present in both of these amps. In fact, I'm not sure I got a whole lot of "improvement" in the sound going from the .5 to the 500 - it is that good!

I would be asking $1000 on Audiogon, but am willing to let it go here to a fellow AN'er for $900 plus shipping and PayPal fees a Rev B just sold on Audiogon for $875). Original box and materials. PM for pictures (until I can take some and post them here).

Thanks for looking,
Bob

[Triode Pete]

I will also throw my modded McCormack DNA .5 "near-Rev A" (which is now called the "Gold" package) SS amp onto the list to see if I can generate any interest.

This amp started it's life as a DNA .5 deluxe, and has had most of the upgrades standard in the McCormack "Silver" upgrade and a significant number of the "Gold" mods as well:

- SMc circuit revision with high performance NP Muse Capacitors
- standard upgrade of the driver board
- standard upgrade of the output boards (includes wiring and a select group of high performance components)
- Cardas RCA jacks GRFA
- Cardas Binding Posts, model CCGR-S or CCBP-S
- Soft Recover Diode Bridge Package
- Rebiasing (per Steve's express instructions)
- Full upgrade of the output board components to Nichicon Gold caps, with KZ and Relcap bypass

The amp was voiced with the help of Bob Crump (God rest his soul), who also voiced the Parasound JC-1 amp for John Curl. The Nichicon Gold caps are used throughout both the DNA .5 and the JC-1. Bob Crump used RelCap RT caps and Nichicon KZ caps as bypasses on the JC-1 instead of BlackGates, because of the propensity of BlackGates to lose their forming/break-in if not constantly played. I also followed Bob's voicing trick to good effect on this amp.

It is smooth and extended with a wonderful presence, free of grit and grain. It gets to the soul of the music. 100W into 8 ohms, 200 into 4 ohms and 500 into 2 ohms - this amp can drive most speaker loads with sufficient power and finesse.

Many ravers have heard this amp in my system and can give you their impression as well. I'm parting with this because I upgraded to the DNA 500, and I have to say that the family sound is very much present in both of these amps. In fact, I'm not sure I got a whole lot of "improvement" in the sound going from the .5 to the 500 - it is that good!

I would be asking $1000 on Audiogon, but am willing to let it go here to a fellow AN'er for $900 plus shipping and PayPal fees a Rev B just sold on Audiogon for $875). Original box and materials. PM for pictures (until I can take some and post them here).

Thanks for looking,
Bob

For what it's worth, I've heard Bob's DNA .5 amp numerous times & it's very special... this is coming from a very finicky tube guy (really only like triodes, especially the lower powered ones). Bob's amp does not have the negative anomalies that most SS amps have... Bob's closest audiophool friends (me included) advised him not to spend megabucks on a DNA 500 and keep his DNA .5 amp and buy some cool speakers instead (like MBL's)!

Bob ignored us! This is an excellent amp (from a guy who generally doesn't like Solid Sand amps). A great price, too!

Pete

[BobM]

Here are some pictures. As you can see there is also some chassis and component damping applied. Some of the internal wiring has also been updated (ground plane) with a silver/copper hybrid wire over the standard fare that was in there originally. It should also be noted that I was able to obtain Nichicon KG Gold Tunes capacitors, which are the finest caps Nichicon makes. Even Steve McCormack was not able to use these in his mods because they have to come direct from the manufacturer and are not readily available.

Front View


Back View


Insides


Output Board

[shep]

Sweet machine. Wish I was over there and buying. This would be on top of the list.

[djdube525]

Slight thread jack... what's the caulk like substance at the base of the caps? Some sort of dampening material? I haven't seen that before. Of course that's not saying a whole heck of a lot. 

Dave

[BobM]

It's a rope caulking compund reasily available at Home Depot, called Moretite. It doesn't dry up and it doesn't melt at temperatures generated within an audio component (although I wouldn't put this directly on a tube). The theory is that caps need to be firmly attached to the circuit board to reduce resonances. This caulk around the base helps to do that without actually gluing the cap down (which is not reversible).

Does it provide an audible improvement? Who knows, but it definitely doesn't hurt at all. It may not look pretty but it is extremely effective at doing this job. It is also used in the cabinet corners for the same reason.

[djdube525]

Thanks Bob! Certainly cheap enough to try it out! 

[mdconnelly]

Bob,

Was the use of Moretite part of the Steve McCormack rev mods or your own?    I may just have to give this a try on my DNA-500.   Like you say, can't hurt! 

[Carlman]

I used a dab of hot glue under caps when I mounted them to the board for that purpose also..
Probably good to put the moretite under the cap if you're installing them.
-C

[shep]

I don't suppose it works on 220v? (help me I'm feeeling an inflamation of my Nervosa!) Hot glue will come off but it can be a battle. I just had  thought about this though; I wonder if the paste used to mount transistors would not work even better? Mcormack does keep a rather low profile. You never hear about them.

[BobM]

The Moretite is not a McCormack mod. Glue is a little too permanent for me. I've had to pull glued caps off of some boards in the past and it really sucked.

Sorry, this amp runs on US voltage.

[BobM]

SOLD - thanks for looking