Which tubes? My amp can except El34, 6L6, KT88, an

As stated my amp can except El34, 6L6, KT88, and 6550's. I would like to know which would give me the best sound for my system? I am running quiksilver 135 monoblocks(which require 6 of any of the previous mentioned output tubes in each amp) into Vandersteen 5's which have a built in sub and 400 watt amp for low end connected with audioquest Kilimanjaro type speaker cable. I am not familiar with the diffrent type of tubes and sonic characteristics so all help is appreciated.

Sort of like asking which flavor of ice cream you should choose? They are all good but different. I am a fan of 6550's and EL34's out of the four you mentioned. I would think that you won't get the power from the EL's that you will from the 6550's or if you do they can't last very long. I have Vandersteen's(not 5's)and run a 6550 based amp which is a great match. I would start there and use them as a baseline or benchmark to judge from. You may end up eventually running one of the others, but good Svetlana 6550c's can be had for about 1/2 the price of decent KT88's so if you don't like them you don't have as much into them.You may be able to talk with your dealer or with Quicksilver and tell them some of your preferences and they may be able to make a rome qualified recomendation. I am going by the idea that if you like the same speakers I do you may like the same tubes.What is in the amps now? I'll take coffee ice cream, thanks.
I have a pair of Vandersteen Model Five speakers with a CAD280 V12i tube amplifier with EL34 output tubes. I have it set to the triode mode for 50 watts per channel and with the Model Five built in subs there is enought power. I find the EL34 more detailed and musical in the midrange than the 6550 or KT88. Of course it is a matter of taste. If you purchase current tubes in production and not NOS you can try more than one type of tube without a significant cash outlay.
I am a fan of all four tubes you listed. My current favorite has to be the 6L6 though. Seeing how you'll need a dozen, they will probably be the cheapest of the four. They are not the best at low end, but your Vandy's amps will take care of that. The midrange is to die for. Female vocals are just awesome. Stunningly awesome. All the midrange magic of the EL34, but sweeter (to me the EL34 sounds a lot like a 6L6, only much drier). They produce a great 3D soundstage. They do pretty well with rock, hip hop and techno as well. I've had best results from Russian 6N3C (a variant of the 6L6), they are fantastic. The Svetlana 6L6 is pretty good. You might avoid the JJ Tesla 6L6, as it has a compressed sound. I liked it at first, but quickly tired of it. Too much loss of micro and macro dynamics. As Maxgain alluded to, it's very much a personal choice. Good luck and happy tube-rolling!

ps - I'll take the rocky road in a regular cone
Agree with Creeper on the 6L6s. He knows his tubes.

The 6L6 often gets over looked, because the EL34 & KT-88
get more press for their classic tube sound.

The 6L6 has better balance and a much cleaner more controled midbass, which will blend well with the solid state bass amps in your V5s.

If you amps can run them, KT-90s are also worth a listen.
Creeper and Kana, I have no problem with what you say about the sound of the 6L6, but you need to know how the powered woofers work in the Vandy 5's. The woofer amps take a speaker level signal from the main amp. They are designed this way to blend and have the same nature as the main amp. If you put in a tube that is "not the best in the low end", the low end will not be the best. I just find 6550's and EL 34's to be more linear top to bottom than the other two, and 6550's have the best bass weight and slam of the bunch. I admit that I may not be not a "classic" tube sound guy as I have been trying to rid my system of some of what I feel are limitations of the "classic" tube sound while keeping what tubes do best in my mind.

Rec's system seems very nice! I would like to hear that combo myself.I love the look of that amp too! Rec, did you have the speakers low end adjusted with that amp when they were set up?
The 5's have room compensation bass EQ built in and may be able to make up for some bass colorations of different tubes for those of you that are not as up on the 5.

Ras10, much more important than which tube you choose( as they all are good in their own way) is what you use for a X-over for the 5. Do you have the expensive model 5 x-overs? If you don't and are using the fixed value X-2's it won't matter how many different tubes you try or how much you spend on Cryo treated NOS tubes. All your signal goes through that X-over and will make or break the final result. Did you just get the amps and the speakers? Did the dealer already set up the bass EQ for you?
Maxgain, that's very interesting about how the Vandy's amps get their signal. Perhaps the 6L6 wouldn't be the best in this situation. They are cheap to experiment with though. I found the Golden Dragon KT88 to have as much bottom end as a Sovtek 6550. The Sovtek seemed a little compressed. But the Svetlana 6550 is great. Very linear. Better slam factor than the KT88.

Kana's suggestion of the KT90 is a good one too, if you can run them. Make sure you get the type 3, matched and tested. They have some quality/reliability issues, but the ones I got from Upscale Audio were very nice. They took a long, long time to burn in and settle down, perhaps 300 hours or so. But in the end, they offered a solid state like low end, and great linearity. In a Sonic Frontiers SFS-40, they outperformed a pair of bridged Adcom GFA-555's in the low end!
Creeper, the Svetlana 6550c is what I use in my amp.It was voiced with those tubes though so I leave well enough alone. I hear that in the right amp the Electro Harmonix 6550 is very good too. But it has to be the right amp! A friend tried them and a first it was great, as they burned in though the sound got real thin and nasty over the course of a few weeks. He has an ARC VT60. He asked ARC about it and they told him that they had the same results with the Electro's in the VT100. Seems to be a lot of variation in different brands, let alone different types of tubes. Makes a recomendation for someone else pretty complicated.
Maxgain, I have the Vandys low end set a 1 with the V12i. This maybe more of a room issue than an amplifier issue. I also used a Rives setup cd and a Radio Shack sound pressure meter to adjust the multiple subs settings. I like the EL34 tubes and retubed with NOS with excellent results. Good luck
I'd also love to hear Rec's Vandys.

Didn't know about V5's crossover pulling it's signal off the output of the main amp, I thought it was line level from the preamp.

I'm running KT-90 type 3 in my SF Power One SE, and they're just starting to settle down and sound as Creeper describes above.

Question for the Vandy guys: I saw a picture from a recent
audio show with a speaker Vandersteen was calling the Signature One, which was the top section of the V5s, but
there's no mention of it on their website. Is it a real
Creeper, if you wan't to do some reading about the way the powered woofer on the 5 is set up, the review in "The Absolute Sound" explains it quite well. It can be found at the Vandersteen web site. I realize after some reading myself that the Vandersteen 5 comes with the model 5, high pass filter, that goes between your amp and pre-amp.I understand that these are very transparent unlike the crappy little WX-2 supplied as a temporary filter for the 2Wq.
It is my understanding that Vandersteen is offering a upgrade to the Model Fives, there is a change in the subwoofer amplifier, crossover and the midrange driver. The upgrade is around 3800.00 depending on how recent your Fives are. This came from my local dealer after he talked to Richard Vandersteen. There may be other changes as well, I only had the chance to talk with him briefly and probably didn't get all the information.
I can say that the Electro-Harmonix 6550 outperform both the Svetlana 6550 and Svet KT-88 in both my Rogue Tempest, and in the Cary SLI-80 Signature. They sounded cleaner top to bottom. The Svet KT88 had a bit more warmfuzzy in the mids, but you definately heard the fuzzy.
Based on the Super sound of the Electro Harmonix 6550, and the stellar review of their EL-34 in Vacuum Tube Valley, I picked up a matched quad from the the tube store for less than $50...
EL 34 tubes are supposed to have less bass than their big-bottle counterparts, but I gotta say, these things sound GREAT. Note, that my Rogue is auto bias, and is made for the 6550/kt88, so the EL-34 tubes are being run much hotter than is ideal for tube life, which certainly affects sound, but if they sound this good run hard, I can only imagine what they might sound like properly biased.

If you're going to try 6550s, the Svetlanas are super cheap, sound most neutral. I prefer the ElectroHarmonix, and hadn't heard of the aforementioned compatability issues, but I digress. Svetlana KT88s are pretty good, too.
Come to think of it, Svet El34s are cheap and good, too. As I said, I prefer the EH tubes...

I can't believe, even though you didn't ask for it, that I'm the first one to suggest that the smaller tubes in your amps are much more likely to affect sound quality than the output tubes.

THis thread has pretty much covered the bases, regarding power tubes... what kind of "little tubes" does your amp use???
Kana813, I have been wondering the same thing about the Vandersteen you are talking about, I though it was called the Reference Monitor. We will have to wait and see.

Using a high pass filter before the main amp with the 5's(and with the 2Wq, which I have) gives you the true benifits of bi-amping, since the main amp has the low bass filtered out. Using the speaker signal from the amp lets the built in sub amp take on the character of your main amp so that they don't sound like two distinct and different things, and keeps the blend more seemless. That's why Rec can get away using the amps in triode for 50watts. Same reason I can use a 45 watt amp and the 2Wq with 2Ce's(which are rated at the same 87db sensitivity as the 5)to get fairly realistic levels

Rec, seems the most info that can be found on the update from the Model 5 to the 5A, is in the adds in both the latest Stereophile and TAS. The add states,"a switch-mode power-factor corrected amplifier supply, a proprietary woven-cone midrange with high-efficency magnet assembly,a new tweeter utilizing a more aerodynamic magnet structure and die cast alloy chassis, and the requsite refinements in the crossover.."
Maxgain- agree with the benefits of taking the low bass out
of the main amp. My SF P1SE sound much better(cleaner/faster) without having to deal with the bass from 50 hz down.

I think the V5s are a true classic design that will hold their value(like the other Vandys). I hope Mr.Vandersteen
brings the Signature One/Reference Monitors to market, for those of us who have smaller rooms or want to roll their bass.

Mahalo for all the info.

Aloha & an early Mele Kalikimaka.
To answer some of the questions,

I am using the vandersteen 5 crossover.

I am currently using in each mono amp 6 Tesla el 34's they came with the amp along with 1 - 12AU7 and 1 - 12FQ7 .

So as I take it the 34's are better on mids and highs but cheap and the KT88 is good bass and good mids and highs but expensive 6550 is between the two including price?

I have been reading and finding out that the Mullard NOS 12AU7 is a worthy upgrade to the sound of your amp?

What does the 12fq7 tube do and why is it such an oddball?

I have also read that the new Svetlana KT88s are really good as well as the EL34's. Are the Svetlana type tube the ones to buy for new production?

One last question, the NOS output tubes worth all that extra money I have read that some of the new production sounds quite good?

Thanks for all the reply's, I look foward to hearing your answers.

I know the NOS guys will scream bloody murder, but I think that the current crop of Svetlanas and some of the Electro Harmonix tubes are they way to go. A dozen output tubes can be expensive, NOS output tubes are down right precious. El34's will end up costing as much as KT88 since you will chew them up twice as fast and still get 1/2 the power while doing it. I still say Svetlana 6550c's are the way to start for what I feel is the least flavoured sound of the lot,or if you like a more romantic (classic tube) sound get the KT's. Check out www.thetubestore.com, they have some good info on the site and they may be able to steer you the right direction. They have some NOS small input/driver tubes like 12AU7 but I didn't see that they had any 12fq7's at all. If you give them a call, they may have feedback from other users of your amp and what works best.(did you ask Quicksilver?) The guys at the tube store are great people to do business with and have fair prices. I got driver tubes from them that one of my old amps didn't get along with and the exchanged them for me, which I thought was great! If you really want exotic NOS talk to Andy at Vintage Tube Services. Have fun!