60 watt Rogue Tubes for Vandersteen 3A Signatures

I don't think 60 wpc is going to get you sufficient decibel levels for anything much more than moderate listening levels. At "live" volume levels, I think the amp will run out of steam.

I'd opt for Rogue M-150 or M-180 monoblocks for these speakers.

03-14-10: Narrod
60 watts of tubes will do ok except for the bass unless that amp has a good amount of current. Otherwise, it will be uncontrolled, flabby and without any real slam.

I disagree. From my experience and research, bass control and tonal balance is primarily a function of the speaker's impedance curve. With a 6 ohm nominal and 4 ohm minimum specification, I think bass quality from a push-pull tube amp with 4 ohm taps will be a non-issue. An OTL or SET amp will be another issue, however.

The issue with these 87dB speakers and a 60wpc amplifier of any topology, is overall volume and available headroom for dynamic peaks.

03-14-10: Narrod
Tvad, OK. I'm just sharing my experience with the speakers and lots of different amps. That's what I heard.

Narrod, from your experience with the speakers, what amps sounded best and what amps didn't work as well.

Can you be specific about models and power specs?

Thanks.

From the Vandersteen 3A Signature website:

RECOMMENDED AMPLIFICATION
100 to 200 watts per channel into 8 ohms.
The amplifier must be stable into a 4 ohm load.

If the manufacturer recommends a minimum of 100wpc, then I'd give that serious consideration.

According to Stereophile's measurements of the speaker in question, the impedance drops to 2.8 Ohms and the sensitivity was measured at 85 dB/W/M.
Unsound (System | Threads | Answers)

That's significantly different than Vandersteen's stated specifications.

6 ohm nominal with a 2.8 ohm minimum does not make for a tube friendly speaker, IMO. I'd stay away from tubes for this speaker based on these measurements.

With the exception of the Jadis Defy 7 I never heard a tube amp bring out the strengths of the 3A better than quality solidstate.

Wendell
Narrod (Threads | Answers)

Thanks for that info, Wendell. SS has certainly been the recommended topology for as long as I can recall. When I saw the manufacturer's specs of 6 ohm nominal/4 ohm minimum, I thought perhaps they were candidates for tube amplification. Admittedly, I got lazy and didn't read the Stereophile measurements section...something I'm always hitting home to others...so I'm guilty of some hypocrisy here.

03-15-10: Unsound
I should say that I have heard the bigger Vandersteen's being run with Audio Research tube amps, and they sounded absolutely sublime.

Are these the Vandersteen models with powered subwoofers, like the 5A? If so, that makes a significant difference since the tube amp isn't responsible for powering the difficult low impedances in the bass frequencies. In this case, there are many folks using tube amps, including Atma-Sphere.