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Tubes 101

I'm very new to tubes. Is there a sonic signature to different tubes? For instance, do Kt-88's have more highs and bass? Do 6550's have better midrange?

It seems like KT-88's, 6550's, EL-34's are the most common, or at least those are the ones that I keep seeing pop up.

I can use KT-88, 6550, KT-90, EL-34, 6L6GC, 7581A, KT66...

In terms of sound, I want it all, and why save $100-$200 on tubes when I'm already this deep in the rabbit hole?

To further complicate things, which brands are better? I'm thinking a matched quad set of Cyro'ed Gold Lion Kt-88's might look pretty sitting in my PrimaLuna Prologue 5....
128x128b_limo
lowrider57's avatar
lowrider57
5,411 posts
 
Congrats on the new Primaluna. Look at the Tube Store plus Brent Jesse provides very good info on tube types, country of origin, and how they sound.
Brent lists of all the brands and their sonic signature. ie: Telefunken...detailed, Mullard...warm, etc.

www.thetubestore.com/Tubes

http://www.audiotubes.com/

Upscale is very good for recommendations, also the Agon Archives.
swampwalker's avatar
swampwalker
5,138 posts
 
Google Joe's Tube Lore and you'll get enough detail to make your head explode!!! Welcome to the "tube side". It's where the music lives.!
xti16
1,525 posts
 
B limo No all 6550's or KT88's do not carry a specific sonic signature. Example a SED 6550 is very linear sounding where a original Tung Sol 6550 black plate is better in the bass and have a midrange to die for (similar to EL34's but better highs and lows). EAT KT88 is also extremely linear with a lot more detail than a SED 6550. The SED KT88 is a lot 'warmer' sounding than the SED 6550 with the Gold Lion KT88 re-issue somewhere in between. The original Gold Lion KT88 is also somewhat linear but a tad dry sounding. Ei KT90 type 2 is has an excellent mid range huge soundstage with great highs and very good lows.

That being said the topology of your amp also plays a part in the overall sound. The little input and driver/splitters also make a difference. Honestly you need to try them and form your own opinion. If the tubes are new give them at least 50 hrs. Some tubes take up to 300 hrs to settle down.
mapman's avatar
mapman
22,099 posts
 
TUbe #s/model merely identify a set of standard parameters that enable different ones to be used interchangeably. These alone do not assure a certain "sound", only that certain models are more likely to work best in a particular design, case by case.

Probably more often than not, two different models of the same tube #/type will deliver sonic differences. How much and to what extent it matters still depends.
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