VAC Sig Ren MK2a Headscratcher

Hi Dev-

Still stock fuses. Actually, it was thinking about the 450's that led me to my present plan! The DNA-500 I already own and is 500w of Class A into 8 ohms, 900w at 4. As you know, the first 50+w of the 300.1's is also class A. The VR-7se's thrive on lots of power and with only the 300's, are barely breaking a sweat. Time to see what they can REALLY DO!!

In effect, I will have MORE POWER THAN YOU, all class A, without killing my budget on the 450's. It should take away a lot of that "450 envy" you keep reminding me I have.. :-) (sorry - couldn't resist.. :-))

My preamp does not have the 6/12v switch, so I am limited to tubes of the 6dj8 line. I can't reveal my tube source yet until I get a backup pair - I'm sure you understand.. :-). I'm also sure there are better tubes for this application than what I got - its all about personal preference, what you are willing to spend, how much research you do, and what sound you are looking for. You really won't know until you start experimenting. I really wanted to try the 8416's, but was not able to due to the lack of the above switch. I just got very lucky in that I really like the first pair of 6v I tried in my system.

As you know, it is very easy to go nuts trying different tubes, fuses, etc. At this point, I am going to focus on the bigger picture of incorporating the DNA-500. As my friend Art mentioned this am, I may also need a buffer or in-line attenuator if the power of the DNA overwhelms the VACs. I will deal with that if it becomes an issue. The DNA is probably 1 of the best SS amps I could try to mate with the VACs, so I am glad I didn't sell it when it came out of my system several years ago.

I'm pretty sure I can reduce the cable quality, as long as silver prevails, in the chain from VAC pre to DNA to bass modules. I'm not sure I would hear the difference between $200. cables and $2500. cables for this bass-type chain. Thoughts?

I see what you are doing but no solid state amp that I have tried to date provides the sonic characteristics of what these tube amps can.

I have had Boulder 2050's, Karan 1200,s, MBL 9008's and 9011's, Bryston 28 Squared just to name a few all with the same speakers.

Using these amps with my speakers ya there was bass but know way sounded like it does as with my VAC 450's, not in the same universe. I'm not just saying that because I own them, it's a fact.

F.Y.I. Amount of power isn't everything, it's "The QUALITY" that matters :-)

I think my speakers might possibly be a little less efficient when it comes to this area than your also and when I tried a pair of 300.1 on my speakers just didn't do it.

Heck by the time you deside to buy a pair they will be $100K Ha! Ha!, they are now @ $80K and Kevin continues to get orders so you know he will continue to raise the price.

My pre-amp doesn't have that switch either so our pre's must be the same besides except mine has the built-in phono added.

I just ordered a pair from Sam who had listed on Gon saying;

Siemens and Halske grey plates 7308 E188CC NIB/NOS best of the best!

These grey plates tubes are the best Simens made E188CC/7308 tubes. According to the date code engraved on the metal plates inside the glass, these two tubes were made in 1967 with the same G7/1C date code. They scored 92/104 and 102/92---almost 100% matched! For Simens 7308/E188CC tubes, these are good as you can get.

So we will find out soon enough.

Cables; that's a whole story on it's own.

Fp, are you sure about the DNA-500 being 500 w/ch in Class A? If we are talking about the amp made by McCormack I believe it is an Class AB design although I don't know how many watts are in Class A? A buddy of mine owned one a while ago and I don't remember him advising it was all Class A power. If you are speaking of another manufacturer then never mind....

Dev- The DNA-500 is the sweetest,most tube-like solid state amp I have ever heard, at any price. I used it in my prior system and am very familiar with how it sounds, especially in the bass area. It is very high quality sound and the rave reviews it received were accurate, IMHO. What I don't know is how it will sound with the VACs, but I suspect it will sound much better than it currently does, as the VR7se's crave power, especially in the less efficient lower bass cabinets, which is what the DNA will be feeding. Ran this past Albert VS last night and he also thought it was a great idea, being familiar with my VACs as well as the McCormack.

Congrats on the tubes - let me know how you like them.

Rgd - I was TOLD by a friend who has had several McCormack amps that mine was all class A. I have a hunch it goes from A to AB at some point, but don't have the manual to confirm where that is. From my standpoint, having heard it extensively several years back, everything I heard sounded like A. In retrospect, I probably should have left out the sound rating comment, since I am *personally* not sure, so as not to unintentionally mislead anyone. Sorry if I caused any confusion by the McCormack "all Class A" comment.

Steve McCormack as quoted in this review:

The DNA-500 is a Class A/B amplifier that's biased fairly rich. Because I don't have to use extremely high voltages, it runs only warm at idle and I don't need a huge amount of heat sink surface area. If it were pure Class A, I would have had to use a huge heatsink to dissipate all that continuous heat. The heat sink in the DNA-500 is actually quite generous and can handle extreme operating conditions, including very low-impedance speaker loads.

As Steve explains elsewhere in the review, the need for extremely high voltages is avoided by incorporating two amplifier circuits, bridged together, for each signal channel (left and right).

Enjoy!

-- Al