KT-120s in LP70S

[Puma Cat]

Originally Posted by repman

Well the KT-120's arrived yesterday , installed, warmed up and biased. I set the cd on repeat and let it play on low levels for about 4 hours as I finished my workday in my home office.

My initial impressions are it has definitely helped the bottom end in fact I had to lower the sub level because it was too much bass. It seems as if the power output has increased as I can hear louder volumes at my normal volume control settings. There is a slight high end glare that I have never heard before with any 6550 or KT-88 tube that I hope will go away as the tubes age in. My overall impressions are very favorable man are these tubes big ( physical size) I am anxious to hear them at 50-100 hours.

Puma see my earlier post I too noticed what I called a glare where things seemed a bit distorted I have about 50 hours on them now and it seems to have gone away. Good luck with yours.

Thanks, Repman...maybe it's just a typical burn-in issue....might be conceivable they alternate from good to bad to good sounding as they burn in. I think I remember the same thing about the Ediswan 6922s I bought for the LP70S when I first got it in Jan 2010. I wasn't impressed with them at all..which was disappointing as they cost me $450 at the time for three 6922s!

Anyway, months later I put them in and left them in and they came around very nicely to where they are notably superior to the stock EH 6922s.

[Coppy]

Originally Posted by Puma Cat

So, I am beginning to wonder the same thing about my KT120s that bgilberti is with his Teflon caps....night before last, when I shut off the amp after a first evening of listening to them with real music for the first time, they sounded great. Last night, after listening to variety of content, they didn't sound good after all....as if they were distorting on louder passages, notably piano, etc and with dark quality....wondering if this is tube burn-in thing, as they sound good, then bad, then good, etc. while they burn in until they start to actually sound good, or if I am indeed crazy. Anyone experience this with tube burn-in?

Nice thing is it's easy to swap out to the original 6550s to check.
_____

Stephen,

The KT120s in my LP140s are doing great, better all the time. More detail, everything. is it possible that the cryo business did something to the tubes they weren't made to withstand?

Bob

[Coppy]

Originally Posted by Puma Cat

So, I am beginning to wonder the same thing about my KT120s that bgilberti is with his Teflon caps....night before last, when I shut off the amp after a first evening of listening to them with real music for the first time, they sounded great. Last night, after listening to variety of content, they didn't sound good after all....as if they were distorting on louder passages, notably piano, etc and with dark quality....wondering if this is tube burn-in thing, as they sound good, then bad, then good, etc. while they burn in until they start to actually sound good, or if I am indeed crazy. Anyone experience this with tube burn-in?

Nice thing is it's easy to swap out to the original 6550s to check.
_____

Stephen,

The more I think about your problem... and hope it's just a burn in issue... the more I wonder about the Cryo process for tubes. Some expensive tubes claim to be Cryo'd but does that mean the parts before assembly or the whole tube afterwards. And has the tube had the cathode coating activated before Cryo?

I've heard that Cryo helps metal conductivity but I wonder two things. First, does it help all metal alloys perhaps, like heat, changing their molecular consistency, maybe not so good for tube internal metallic structures meant for hot environments. Secondly, part of the secret "magic sauce" of tube manufactures is cathode coatings. The filament of most tubes heats the cathode which is then the source of electrons streaming throughout the modulation of the grids to the plate. But it's not the cathode itself that releases the electrons but the "secret sauce" coating applied to the cathode. After the tube is made the cathode is often flashed with a high voltage shot to activate the coating. In any case, I wonder if those important coatings are meant to be Cryo'd and how they would take it after being activated.

Hope this all clears up for you quickly.


Bob

[daimo]

Hi Puma Cat,

I need to get more power for my LP70s since I just got new speakers (AE1 Mk3 SE) recently. Do you still recommend the Cyroset KT120?

Thanks in advance,

Daimo

[daimo]

Hi PC,

Do you still recommend the Cyroed KT120 for the LP70s?

Thanks and best regards,

D

[Puma Cat]

Daimo,
The KT-120s work great in the LP70S, but they will not produce more power. They do sound better, have better bass and dynamics and are more durable, but to increase power, C-J would to rewire the transformers.

[daimo]

The current sylvania 6550 I use seem to have trouble giving me bass authority ... so I wonder if the KT120 will be the solution.

thanks PC

D

[Puma Cat]

Originally Posted by daimo

The current sylvania 6550 I use seem to have trouble giving me bass authority ... so I wonder if the KT120 will be the solution.

thanks PC

D

Well, the bass with the KT-120s is definitely better than with the 6550s.

[Sunnyboy1956]

Old thread. Me new. Did the switch from 6550s to KT 88s and now KT 120s in a CJ LP 70S. No comparison the 120s way better in all parameters though sound a bit etched at times. Could be the new speakers breaking in.
Pradeep

[ronenash]

Originally Posted by Sunnyboy1956

Old thread. Me new. Did the switch from 6550s to KT 88s and now KT 120s in a CJ LP 70S. No comparison the 120s way better in all parameters though sound a bit etched at times. Could be the new speakers breaking in.
Pradeep

Which 6550 and kt88 did you use? I was thinking of trying Gold Lion KT88 in my LP125mSE.