Pass amp vs McCormack with Silver/Gold upgrades...

OK, I'm trying again. My purchases in the past have benefited and been guided from help here, and I hope my first SS amp purchase might benefit similarly. I've read a lot and my interest has focused on two amps (thought the Blue Circles are intriguing).

For the cost of buying a DNA-1 or .5 and getting $1000 to $2000 of upgrades, I can buy a pair of used Pass Aleph amps (more or less) such as the ones on Ebay right now. I have not heard either, but am going on lots and lots of reading.

Is anybody able to contrast the sound I might get with these two options? Or make an educated guess? Uneducated guess? Toss a coin?

Any comments would be sincerely appreciated.

Hey Jim, good luck, I hope that someone can answer your question. I looked on Ebay and I didn't see any pair of Pass amps listed, are they gone? All I see is a XA 30.5, which is a stero amp for $3680.

I'm curious as to how you've narrowed it down to these two brands. I'm not knocking them, Pass and McCormack are both good amps. I'm just curious as to what you are trying to accomplish. What speakers are you driving? How big is the room? How much power do you think you need? Why brands like Rowland, Classe, Coda, Clayton and others seem to be off your list.

Again, good luck in your quest.

Thanks John. I posted a long reply but it doesn't seem to have succeeded. In short, I read many comparisons in forums of X vs Y. These two amps seem to rarely be the less preferred in such discussions.

I have ProAc One SCs, with a Marantz 8B and CJ PV-5. I want more clarity. I have listened to my ProAcs against many other speakers at dealers and their systems were much better than mine. The ProAcs are capable of much more clarity. I thought I'd try a SS amp and new preamp. 11x12 room.

Thanks for asking.

Interesting. ProAc's are very nice speakers and your amp and preamp are legendary products. I would think the CJ is more of your problem than the amp though. CJ are known to be very musical and warm, but so are ProAc speakers and your Marantz amp. I think you have found out that too much of a good thing is not good. CJ is generally known to be warmer than the Marantz amp though. I think you'd be better off changing preamps first, but that's just my humble opinion.

I'd look for a VAC or ARC preamp. Both of those brands are much more revealing than a CJ, with perhaps the ARC being the most transparent. I have warm speakers too (Soliloquy 6.3i's) and I'm very happy with my Coda Model 11 amp and VAC Auricle preamp. I had a CJ Premier LS 16 mk II for a while, but found it to be too warm when combined with warm speakers.

Just be careful if you get a Pass or McCormack amp, as they have relatively low input impedences, which means they don't mate well with many tube preamps.

John, thanks very much. Can you educate me a bit about the impedance matching issue with mating preamps with amps?

Your system sounds really nice. I do agree the PV-5 is probably the weak link limiting clarity in my system. Uncle Stu (don't see him here but he is on that other place) has offered to turn my PV-5 into a PV-11 for a fair price. I also have been reading up on ARC, and I think an SP6, SP8, SP14, or LS5 would be great to try but as I'm pinching pennies for a land purchase they are way above my budget...they all seem to be $2K or so. Another option is one of those

I can pick up a SS amp to try a lot cheaper, even a McCormack. I'm also curious about how the bass will sound compared to my 8B. I may pick up a B&K ST-140 as a start; they are very cheap.

I may start a thread on the impedance thing, I should understand this before investing too much...

Thanks much,

There seems to be a general rule of thumb here on the boards that a 10:1 ratio of amp to preamp is sufficient. That means that a preamp with a output impedence of 600 ohms should be fine with any amp with an input impedence of 6Kohm or higher. I don't really agree with this, I tend to think that ARC's requirements of 25 or 30:1 as a minimum is a better estimate. Meaning a preamp with an output impedence of 600 ohms should not be mated with a amp that has a input impedence of under 18K ohms. Generally the higher the ratio the better. For example, my preamp has a 600 ohm output impedence and my amp has a 50K input impedence. When you have an impedence mismatch you tend to hear it as rolled off bass and highs.

If I remember correctly, the McCormack and Pass amp have input impedence's in the 10K-20K range, which is relatively low for a power amp. Many tube amps have an input impedence of 100K-200K ohms. Tube preamps have higher output impedences than their solid state brethren. Many solid state preamps have output impedence under 100 ohms. So the danger is when you match a SS amp with a relatively low input impedence with a tube preamp with a high output impedence. I don't know what the output impedence of your CJ preamp is.

IMHO, going from a PV-5 to a PV-11 will not accomplish much, it's still a warm sounding CJ product. You seem to be looking in around the same price range that I am now in, as I paid $1125 each for my Coda Model 11 and my VAC Auricle. I have owned much more expensive gear, but these units can hang with just about any gear. The VAC is a full function preamp, so I don't need an additional phono stage. Also, I like the Coda Model 11 a lot, because after living with tube amps for a few years, I find that Class A solid state makes it the easiest to transition back to solid state gear. The best SS amps I've ever owned, Coda, Clayton Audio and Threshold, were all pure Class A designs.

Another thought is to try a used VAC Avatar Super integrated amp. Those amps are fabulous, you should be able to get one for under $3K and it will be very hard to beat for that $$$. Your speakers are a bit low on the sensitivity side, but are 8 ohm loads and you have a relatively small room, so 80 wpc of tube power should be plenty. The VAC preamp section is much faster and more transparent than a CJ preamp.

Hi John. Just to try something SS without really opening my wallet I just picked up a like-new B&K ST-140 (105w version 2). I know these are a bit weak in the bass and high end, but it will be an easily recovered data point. I waffled between that and an Aragon 2004 MkII also on Ebay but my wallet won.

The only info I can find on the CJ PV-5 output impedance is 200 ohms. The ST-140 input impedance is 24Kohms (Aragon 2004 is 22Kohms). What do you think? I have never had a SS amp aside from receivers in college.

I looked in Audiogon for an Auricle and Coda, Clayton Audio and Threshold amps. There is a Threshold (above my budget) but none of the others. The Avatar sounds very attractive...there is one but it's 4400, a bit special it seems. Moot though as the 3K is out of reach right now.

Many thanks for the thoughts. I think the first thing right now is see what SS sounds like, keeping in mind I'm at the low, low end. I understand some cap changes can alleviate the wooshy bass and rolled highs in the ST-140 and at this price point I would not be afraid to try it myself.

As mentioned I probably need to be working on the preamp instead of the amp so I'll be keeping my eye out. Should you ever decide on an upgrade on the pre, let me know. I'm curious how the Auricle sounds relative to an ARC, CJ, or Audible Illusions...

Just looked up the input impedence on the DNA-1, 100Kohms!

Really? 100K? I always thought that McCormack's were around 10K and Pass around 20K. If your CJ is 200 ohms, you shouldn't have a problem, even with 10K. However, I think you are looking for something with more resolution than CJ.

I've heard the B&K's, but never owned one. I did own a Aragon 4004 mk II many moons ago, it was a nice amp for the $$$. When considering preamps, CJ and Cary are at one end the the tonal spectrum, the rich, warm vibrant end. ARC and VAC are on the other end of the tonal spectrum, the transparent, high resolution end. Audible Illusions is more in the middle, but leans towards the transparent end.

With the 24K inpedence input you should be alright with any preamp with an output impedence under 1Kohm.

What kind of cables are you using? If you're using warm cables like Cardas with warm preamp like CJ and warm speakers like ProAc, that also could be a mitigating factor. Let me know what you think once you get the B&K hooked up.

I hate to be Debbie Downer here, but there is little comparison btwn a B&K and a stock DNA, let alone a modified one.
John, will do. Thanks for the comments on preamp characters, that was incredibly useful. I should give you a percentage of the money you just saved me.

Cables? Well, um... I went to the local car/home hifi place, and asked for the best car audio cable they had; I think I got 30 feet for $30. You see I am just setting my system back up after years in storage, and am also the proverbial underpaid academic. So I need to take it a step at a time, but indeed, cables have been much on my mind as I focus on improving clarity. I am eager to find out what impact that will have. Would you have any recommendation, given you know my situation somewhat?

Swampwalker, I would love to read a long exposition on the sonic distinctions between the ST-140 and a DNA so please feel free if you feel like it. I did search for all I could find on that without very informative results.

Certainly you are right though, and I did make a bid on the DNA .5 Deluxe but didn't get it. Which highlights one big difference between the ST-140 and DNA: the price. My offer was 3x what I got the ST-140 for and I still didn't win!

Do you think the B&K will not tell me anything useful about how SS will sound compared to my 8B, that will apply for the DNA as well?

I do plan to get a DNA but am unfortunately not a doctor, nor a lawyer, so it will be a while...the problem with college is you choose a path when you are too young to realize how important money is going to be once you can't call up your parents in an emergency....:-)

07-11-12: River251
...the problem with college is you choose a path when you are too young to realize how important money is going to be once you can't call up your parents in an emergency....:-)

Haha, ain't that the truth. I have 3 sons, 2 are out of college and working now, though neither is making as much $$$ as we all expected. The youngest is due to graduate next May. Hopefully the economy will pick up down the road. I worry about my kids's looking pretty bleak.

Swampwalker does have a point, but I understand that you are just curious as to how a solid state amp may sound in your system. I have a feeling that the B&K will be a disappointment, as it is far from the best SS and going back to SS after tubes is not easy to begin with.

As far as speaker cables go, ones that are relatively inexpensive but are lots better than the standard drab are Clearview Helix from Mapleshade. I've only actually used the Double Helix, which I felt beat cables that cost 2-3 times their price, but the Helix will save you even more $$$. You can save even more if you can find a used pair. They don't come up often, but I see them every once in a while.


John I'm amazed there may be a speaker cable for that price range. Would you call these on the bright side?

I fully expect the B&K will not replace my 8B. But I have been intrigued for some time. It's costing me $27 in shipping, and I am sure I can pretty much get my $200 back on Ebay, as it looks new. It's a data point. I'll learn.

Without any upgrades to the stock DNA-1, I would most definately go with the Aleph's as they will sound more refined and sweeter.

The economy is still dragging along and I believe since the price of gasoline has dropped, this may be the booster shot the economy needs. But them wallstreet bankers are still determine to destroy any headway made. JP Morgan/Chase just lost 4.4 billion on a bad deal but did fire the executives responsible. Boy that definately makes me feel better.
River251: There is a DNA 0.5 here on A'Gon right now with upgrades by Steve McCormack, asking $649, which looks like a whole lot of amp value for the $. Jmcrogan2 is indeed correct that the 10:1 impedance "rule of thumb" should be taken with a large grain of salt, and in many instances should be much higher. When I paired the CJ Act 2 Series (500 Ohm output impedance) with McIntosh MC452 (22 KOhm input), there was a loss of air, high frequency detail and bass roll off, such that neither of these great components showed its true colors.
Phd, thanks very much. Don't let's get started on the economy...

John, thanks much, I've spent some time this morning reading threads on the Mapleshade wires and will get both speaker cables and interconnects to try when I can.

I wouldn't say that the Mapleshade are bright, but they do lean toward the transparent side of neutral. I have heard brighter cables though.

Jmcgrogan2 said-
I have a feeling that the B&K will be a disappointment, as it is far from the best SS and going back to SS after tubes is not easy to begin with.
Yeah, that was where I was going. I'd call them entry level high end while the DNAs, esp. the 0.5, were high end bargains. OTOH, @ $27, what's not to like??? As far as cables go, lots of 'goners like Paul Speltz Anti-cables @ $10/ft.
Sorry River251, it was not my intention to redirect this thread but jmcgrogan2 mentioned the economy previously and got me going.

I could not find the DNA 0.5 with upgrades only the deluxe model. It has probably already been sold as items are automatically deleted upon a final sale. It is also important to find out when the upgrades were performed as Steve McCormack added star grounding which lowers the noise floor thus allowing the most intricate details to come through.
Thanks all. Actually Swampwalker I called Paul to see if he would make me some 6" adapters to go from the tiny screw posts on my vintage amps to some bananas, and buy some jumpers, and he called back this morning. Before I got off the phone he sold me 48 ft of wire and 8 bananas (plugs, I mean) and he threw in some solder so it looks like I am going to try the antiwires before I try the mapleshades. I have no discipline.

Phd that's the .5 I was talking about. I offered him 500, he countered with 600. It was just too close to what I can get a 1 for, since I'm going to eventually get Steve's silver or gold upgrade. Not to repeat myself but I think Chris said after the upgrades the .5 vs 1 advantage will be diminished and it will be good to have the power for unknown future speakers. Besides I should not have even entertained spending that right now. My aim is more clarity and I think people who have suggested focusing on the preamp right now are right, so these funds should be going that way.

Didn't mean not to talk about the economy, you can talk about it all you want, I was just refusing to participate. If you think I'm bad going on and on about hifi....besides I get more than enough economy keeping up with the market in fear for my 403B.

I know it has been discussed before as to the Mccormack DNA .5 versus the DNA 1 but honestly after owning both I thought they sonically sounded the same accept I would give the DNA 1 the final nod because of its power and like Chris said, you will not have to worry about upgrading to a higher power amp in the event you make a speaker change.
Hi Guys, well I've spent a few days with the B&K ST-140. Thought I'd put it in a new thread though, as some person might be interested but might not find it in this McCormack thread.

To wrap the McCormack topic though, I won't be buying one, as I'll explain in the new thread.

Thanks to all of you for your input and help. Sure makes this hobby more tractable.