Mono Block tube amp or Stereo Tube amplifier?


I am thinking about buying a tube amplifier but I am caught up in deciding on Stereo or mono block tube amplifier. Can someone point out the pros and con of each? and which do you think is better?
almandog
Mono block is the way to go. Check out the VAS line, warm sound, can drive almost all speakers and have great resale value as you move up to more powerful mons's.
The main advantage of a monoblock is that it does not share power supply and grounding circuits with the other channel. This can result in better bass, lower distortion (greater transparency), less crosstalk (more imaging information).

I run long interconnects and I have a balanced line system, so the interconnects are inexpensive (and 25 feet long). OTOH I keep my speaker cables as short as possible, as that allows a tube amp more definition and better bass delivery; something that is a lot harder with a stereo amp.

Monoblocks rarely draw more power, nor do they make more heat if they are the same power and class of operation as an equivalent stereo amp.
Two monaural amps of a certain power are no different than a stereo amp of the same power for each channel. Basically you cut the chassis in half and duplicate the power supply, perhaps at a lower power level suitable for one channel.

The advantage of monoblock amps is that they can be located right next to the speakers, and for high power systems, you can pick them up without throwing your back out.

In a well designed stereo amp there is no crosstalk between channels (contrary to a common idea).

I have five monoblocks in my multichannel system.
Mono-blocks are able to deliver double the amount of current to your loudspeakers. If you have hungry speakers, like to listen at loud levels and require punchy bass, these may be the biggest reasons why you would want monos. Yes, monos offer a bit more separation of instruments than stereo units and you can use shorter speaker wires, but those advantages alone may not be worth moving to monos. In short, if you have less-than sensitive speakers, prefer a particular amp and like to rock the house - running those amps in mono is worth it.

BTW:
- No, watts are not watts. Think current delivery.
- Musicians like tubes because they sound better to their ears.
- Tubes are great for rock music provided you have enough current delivery.
Tube amps tend to produce heat and monoblocks will heat up a room faster than a stereo amp, as they generally have more output tubes (but not always).

Monoblocks mean you will need to buy twice the number of tubes. This can be an expensive difference.

Monoblocks are twice as powerful as a stereo version of the same amp, but if you can get away with lower power, you are better off, as additional output devices mean a more complex circuit and less pure sound.

Monoblocks tend to burn more electricity (because there are two of them).

Monoblock amps can be positioned much closer to the speakers, thus allowing really short (and thus cheaper) speaker cables.

Monoblock amps can be work if, like most of them, they do not autobias. My monoblock / stereo tube amps autobias, so this is not an issue for me.

Monoblocks tend to be more difficult to resell, as they cost twie as much as a comparable stereo amp (there are factors that make them easier to sell, but this was not intended to be a tutorial in economics).

About tube amps in general, it is a very expensive sport, as a tube amp that can truly control woofers in dynamic loudspeakers (as opposed to planars, electrostatics, etc.), which is what most people run, is very hard to find, and the few that can are very expensive (like $10k+ retail as an entry-level point, with $25k-$30k retail being more typical). Your speaker is very efficient, but drops below 2 Ohms in the bass and has a nasty phase angle at 20 Hz., meaning only a small handful of tube amps will work with your speakers. One relatively available and relatively affordable tube amp that can drive a 2 Ohm load is the Sonic Frontiers Power 2 stereo amp and Power 3 monos. VAC's Renaissance amps and the CAT amps can as well (the CAT's are the best I am aware of in this regard), but are more expensive.
Bojack -

I don't know if RUSH uses tubes and I certainly don't know why they use tubes. But if I had to guess I would say it is because of the way they can make them distort.

The point I tried to convey is that tubes are better able to provide the delicate nuance available to the discerning listener of acoustic music. Amplified, cacaphonic noises can be conveyed by any kind of amplification, it is true, but why waste tubes on it?

Similarly, one cannot audition any kind of equipment with electrically amplified music because there is no live standard to compare it to. It always passes through electronics and it always comes through speakers. The best you can do is compare speakers to each other.
Better seperation, less cross-talk, can be place very close to your speakers and away from the rest of your rig. Cons- two PC and access to outlets, long IC but short SC , cost more.
Small gain in performance.......but gain nevertheless. Monos don't guaranty good performance. The synergy and quality does.
Check out -Antique Sound Labs- Hurricane, 200 watts per channel in standard mode and 100 watts per channel in triode mode. They are monoblocks and should work well for your application. I have only heard them run full range and not on your speakers, but they sounded very nice in the triode mode.
Macrojack, is this why Rush uses tubes? My point is that watts is watts, and tubes do just fine with any type of music : )
Almandog in your current setup I would always look at keeping things simple therefore, a sweet midrange/treble stereo tube amp is preferred IMO. If your truly going to commit to a tube amp you really have to select an amplifer that will help bring synergy and sonics you truly want in the midrange/treble area. I agree, tube rolling will allow you to change the sonics for Legacy Audio 20/20 (nice speaker BTW).

I wonder how much you really gain with MONO amps in the midrange/treble in your current setup. Most great MONOS will cost a lot so look at price/performance ratio hence, stereo tube amp may be a better cost alternative. Tube rolling alone for my two MC275 run in mono...$800 plus to do it right.

The key here is the external crossover which has to deal with two different amplifiers and the potential gain mismatch. The independent output-level controls will have to balance the levels between the woofer and midrange/treble amplifiers.
Almandog, The Onix really is more a power amp than an integrated. I use a preamp in front of it and it sounds great.
My experience has been that the big game animals of audio usually recommend mono blocks.
Larry,

I already have a preamp and a solid state amp (McIntosh C2200 and MC402 respectively), and I see the the Onix SP3 is an integrated amp, therefore I would not need it. Can you recommend another Tube amplifier in the Onix price range?
Start with why you want tubes. Then think about how much you can spend. Personally I believe that tubes are for acoustic music. I see no reason why anyone would benefit from reproducing heavy metal at 95 db with tubes. That is SS territory. Tubes are for sensual, subtle sounds.

If you still think you want tubes, or if you now see bi-amping with SS works better for you, the rules are the same. Two chassis cost more than one. Monos enable you to shorten speaker runs. Monos, even if they share a chassis will have separate power supplies allowing for better separated channels. Then there are layout implications, bragging rights and forum topics.

Remember, though, that bi-amping is not a goal but a means to reaching one's goal. Unless you need to do it, don't bother.
I am using Legacy Audio Focus 20/20 speakers, and I have McIntosh C2200 Preamp, McIntosh MC402 amp, McIntosh CD player, and VPI Scout turntable. I am considering Bi-Amping, with tubes driving the Mid/High, and the MC402 driving the woofers. So that is where I am hang up between getting a mono block tube or stereo tube amp. I do realize that I have to use an active crossover in the Bi-amp configuration since the amps are different. Any thoughts on Mono blocks tubes versus stereo tubes amps for this application?
A great place to start in tubes is an Onix SP3. Hands down the best tube amp out there for the money. You can tube roll all the tube to change the sound til your hearts content. Also there are forum threads galore about this amp. As far as stereo or mono is concerned, I would go the stereo to start to see whether you in fact are a tube type of guy. Some people aren't.