Tube amp for Magnepan 3.5 with autoformers.

I drive my 3.6's with an Audio Research VT200 (200 w/ch) tube amp with the autoformers so the amp sees an 8 ohm load. I like how it sounds, the autoformers took a while to break in but are well worth it. When I use my D400 MKII I do not use the autoformers, the amp is solid state and will deliver more power (400s/ch)into 4 ohms than the VT200 will. The tubes sound the best.
There is a VT200 on Audiogon for $2995 with new tubes, a pretty good deal. Good luck.

Steve McCormick reports that using his amps with the ZEROs to drive 4 ohm speakers sounds better than driving the speaker directly, despite the fact that his amplifiers are easily capable of driving 4 ohms.

I interviewed several solid state amplifier manufacturers at CES this year, all of which made amps that are considered 'high current' and easily double power into 4 ohms. There was a consensus amongst them; transistor amplifiers will sound better into 16 ohms than they will into 4, apparently due to the effects of current through the output devices, which is deleterious to the sonic performance **even though the amp easily makes the power**.

This is a powerful argument for using the ZEROs with any transistor amplifier as this precisely what it does: loads the amp at 16 ohms.

You will loose power this way with a transistor amp- a 100 watt amplifier will suddenly be putting out 50 watts, but it will be a better-sounding 50 watts.

The effect of using tubes with the ZERO is different- in many cases you do get better sound, but in some cases you also get more power and wider bandwidth, especially in the bass. Most transformer-coupled tube amps suffer a loss of power and low frequency bandwidth when running on the 4 ohm taps; the ZERO is a way around this.

I'm using a Mac tube amp with 1.6's and nordost cables and am very pleased. I crank it up on occasion and no issues with the sound or the amp.

Guys, just a thought:
the 3.5s are bi-wireable, thus, bi-ampable... wouldn't 2 tube amps (of the same kind/type) work some magic?

2 tube amps of different kinds/types would need some cross-over, but 2 of the same would not as a preamp with 2 outputs would do just fine.

what do you think?

i hope this is not OT :-|

Thanks
.e.

Thanks for all the input. I spent a couple of hours with my buddy finding the best speaker placement and that improved the sound. After finding the right location we put the spikes on the MYE stands and that also provided better focus. I like the sound of the 9200 but would still like some tubes in the mix, so I may stick with a SS amp and go with a tube pre. I do not listen extreamly loud so I wonder if a 100 watt Plinius amp would be enough power. The 9200 has 200 watts a channel but I don't belive it doubles into 4 ohms. It has enough power for my listening levels.

I've had extensive experience with 3.5R's and you need serious tube power to make them work as well as with a high quality solid state amp. Unfortunately, high power tube amps don't come cheap. We're talking a mandate of 150+ watts.

The autoformers will help (expecially with OTL's) and cure a few problems. Fortunately, Maggies are a mostly resistive load, so they don't change sonically as much as other combinations. IMHO, this applies to speaker cables as well, I wouldn't throw a lot of money at speaker cables expecting great change, just subtle changes, so watch your wallet and audition as necessary.

To be honest, I'd consider sticking with the Plinius line with a dedicated amp and using a tube preamp to help get the sonics timbrally more correct. I was told a long time ago by a dealer that if you have Maggies, you need tubes somewhere in the system. I would have to agree based on my own experience. Another great match seemed to be big Pass amps. Bryston mono's are maybe less sexy, but seem to be a very good match as well with most maggies, especially the larger panels.

With all that said, large VTL's tube amps will sound a little sterile, but have great control. Big OTL's will ruthlessly reveal upstream problems, but strike a nice balance and sound very natural. Big ARC tube amps like VT-200's set up as monos will be all right, but may grenade with a tube arc-over so they're a bit stressful during loud passages. LOTS of tubes per amp will sound nice and look great at night, but you will need all those tubes to make the 3.5's sound better than a good SS amp.

Also, watch your midrange fuses during loud passages, when the fuse pops, it seems to shovel more power to the ribbon tweeter which is more fragile.

Good luck,
RFG

You only need autoformers if your amps can't support a solid 4ohm load that Magnepans require.

Try some Art Audio amps,call Joe Fratus he is very
knowledgeable on this issue.His amps are really good.
I do own the Concierto paired with my Diapason.

Something like this should do well:

http://cls.audiogon.com/cgi-bin/cls.pl?ampstube&1207754442

Note: I don't know the seller.

Dave

Pal,
I’m a believer in tubes (preamp & amp) but don’t sell short your Plinius 9200!
You might find out that the sound that comes out of your 3.5’s is more desirable from the tube-like sound from your Plinius than from less expensive tube amps.
Just a thought.
Best regards…

I too have 3.5Rs. 3 weeks ago I bought Wyred 4 Sound SX 500s which I am using on my mid/bass panels. I am using a PS Audio GCA 250- Level 2 mod by Underwood on the ribbons (it is for sale). The only tubes in my rig are in the Raysonic 168. I also use an active XO to attenuate the XO points and volume of each amp. It's killer!

i gave up trying to drive my maggies 1.6 with tubes. i had Rogue m120 and it was not enough, just too blah sounding though with very sweet tone. surprisingly manley stingray worked well with a lively sound but still not very loud. i ended up selling them and now own 97db audio note speakers and set amp

something like Atmosphere otl amps would work well i imagine

btw i did try the autoformers and liked them but not enough of an improvement

cayin 100T, tube, used. You will never hear sweeter vocals and jazz.