Sovtec 6550's vs JJ KT 88's

throw_this_away · Post by **throw_this_away** » Mon Mar 13, 2006 3:17 pm

Sovtec 6550's vs JJ KT 88's?

Can anyone give me opinions on which sound better with tube amps and rics (I like mid growl)?

I use a 200W Traynor YBA200 with 4x Sovtek 6550's, and Sovtek 12AU7 and 12AX7's in the preamp.

Also, if anyone has experience with JJ preamp tubes I might also be interested in opinions. I am looking to get a backup set of tubes for my amp. From what I can gather, the KT 88's are cleaner and more hi-fi sounding than 6550's, and I am not sure that I am looking for that... as I like dirt.

edski · Post by **edski** » Mon Mar 13, 2006 3:35 pm

I've used Sovtek's in my guitar amps. Those Ruskies do know how to make a good audio tube!

I liked Svetlana's the best, and the Sovtek 12AX7 flavors are all really good. Had a set of Czeck tubes, JJ's I think, that were really sweet.

But I don't know if guitar amp experience carries over to a tube bass amp...plus I use 6L6's in my Peavey Triumph.

soundmasterg · Post by **soundmasterg** » Mon Mar 13, 2006 4:57 pm

I have a Sunn 200S that I rebuilt and modified, and I used JJ KT88's in it. I really love them, and this is the second one I've used them in. They sound very nice, and are a very strong and long lasting tube. In the past the Sovtek 6550 wasn't very good, but they improved it, so it is reliable now. I still don't like the way they sound as compared to the JJ KT88 however. The JJ KT88 has higher ratings so depending on what the voltages are in your amp, it will hold up better and last longer, and may even put out a couple watts more power. As far as the sound comparison, they aren't really cleaner or more hifi sounding than the 6550's, they are just slightly different sounding. I think you would probably like them better.

As far as their preamp tubes, JJ makes two different 12ax7 types. The ECC83S is high gain, and has a good clear sound with lots of presence and punch. Sometimes it can be dark sounding compared to other 12ax7 types depending on the circuit because of the extra gain. The new ECC803S is a lower gain tube, and has a long plate inside the tube, so it is more sensitive and has more high end response, but also tends to get microphonic easier. I really like the sound of these ones for the input tube in the amp, and then I use the ECC83S or some other brand for the other stages in the amp.

JJ makes some good quality tubes that are hard to beat. Some other good options for the power tubes would be the Winged C/SED 6550C, (I use these in my Ampeg SVT and liek them), the new russian made Tung-Sol 6550 reissue, and the EH 6550. For the preamp tubes, other options would be the EI 12ax7, EH 12ax7, Sovtek 12ax7LPS, chinese 12ax7, Groove Tubes 12ax7M, and the Winged C/SED 12ax7. You can get all of these from www.tubesandmore.com or www.newsensor.com among other places.

jnbass · Post by **jnbass** » Mon Mar 13, 2006 9:01 pm

hey them JJ have a "blue tinted" KT88 that looks really cool.

Never liked Sovteks-are they older models?

Go with the JJ's or the new Tung-Sol reissues!

throw_this_away · Post by **throw_this_away** » Tue Mar 14, 2006 2:37 am

can you mix blue and red tinted? is the glass just tinted red or blue?

I think the sovteks are new... they came with my amp when I got it new in the fall

billy_sacco · Post by **billy_sacco** » Tue Mar 14, 2006 3:18 am

Well you would probably want to buy matched tubes which most of the stores sell in sets. And you know I always heard it the other way around. I always heard 6550s were kind of soft tubes and KT88s are supposed to get crunchier. Maybe I was wrong I don't know. www.tubestore.com has reviews and most of the major tubes in stock. The Sovteks are solid tubes used for years. I would really like to try the JJs though you are tempting me.

jnbass · Post by **jnbass** » Tue Mar 14, 2006 8:37 am

6550 are know for their 'clinical' sound, at least in bass amps.

Yes it is better to use matched pairs/sets in your amp, unless you can individually bias each output tube or have a cathode bias amp.

At least thas what I think

Thas right innit?

throw_this_away · Post by **throw_this_away** » Tue Mar 14, 2006 9:56 am

yeah, the YBA200 is a self biasing amp. Cheezy, but red/blue/red/blue sounds tempting for my power section as I can get that combo at no extra cost.

billy_sacco · Post by **billy_sacco** » Tue Mar 14, 2006 9:56 am

Yeah but if your amp's volume knob doesn't go to 11 just retire.

edski · Post by **edski** » Tue Mar 14, 2006 1:00 pm

I guess the JJ's are getting some raves...

JJ KT88's in it. I really love them, and this is the second one I've used them in. They sound very nice, and are a very strong and long lasting tube.

I beat the **** out a quartet of 6L6's with my guitar for FOUR YEARS. Last year they shoulda been replaced, but hey, I was STUNNED when I put the Svetlana's back in the dates on the Svet's box...I really didn't think it was that long!

Actually I think one of the JJ's is still in...one of the Svets was busted IIRC...but the amp doesn't get used like it used to since I've been playing bass again. I'll have to put out an early X-Mas gift suggestion...

Honey, a quartet of Svetlana or JJ GL6L6 amplifier tubes would be nice. A quartet of Sovtek 12AX7's would be cool too! Then I could put another amp in the room with the cat!

jnbass · Post by **jnbass** » Tue Mar 14, 2006 8:27 pm

Telefunken 12AX7's!

kcole4001 · Post by **kcole4001** » Wed Mar 15, 2006 6:05 am

I just retubed my Peavey guitar amp with all JJ's & it sounds great. Nice & warm, 12AX7 preamp tubes & EL84 power tubes. I got them from Charlie's site, VTV. Good prices & fast service.