Substitute El-34 for KT 88s and 120s

RE: Substitute El-34 for KT 88s and 120s, posted on October 20, 2014 at 18:18:49
AbeCollins Audiophile Posts: 46306 Location: USA Joined: June 22, 2001 Contributor Since: February 2, 2002	I'm not familiar with your amp but in general I might expect to hear a more harmonically rich and 'lush' sound from the EL34. Power output might also drop but may not be noticeable depending on your speakers.

RE: Substitute El-34 for KT 88s and 120s, posted on October 20, 2014 at 19:31:33
TGT Audiophile Posts: 531 Location: Kentucky Joined: December 6, 2002	My speakers are Thiel CS 3.6s.

RE: Substitute El-34 for KT 88s and 120s, posted on October 20, 2014 at 20:07:10

AbeCollins
Audiophile

Posts: 46306
Location: USA
Joined: June 22, 2001
Contributor
Since: February 2, 2002

Thiels and tubes are a match made in heaven!

My Thiel CS2.4 speakers driven by a pair of Manley Neo-Classic 250 EL4 monoblocks were outstanding but those Manleys put out a hefty 250wpc of EL34 magic. I'm not familiar with your monoblocks but if they're fairly powerful for your Thiels, I think you might be pleased with the EL34 sound.

What are you hoping to achieve with the EL34s? KT120s are also very nice. In fact, I'm enjoying my tube integrated with KT120s as we speak but through my smaller Tannoy speakers in the home office.

RE: Substitute El-34 for KT 88s and 120s, posted on October 20, 2014 at 22:10:04
Mick Wolfe Audiophile Posts: 3365 Location: AZ Joined: October 10, 1999 Contributor Since: September 4, 2000	I've heard KT 120's described as EL 34's on steroids. I've preferred the results using either KT 120's or Genalex KT88's over any EL 34 I've tried in either of my Bob Latino amps. The bass, for one, was better in both cases. As always....YMMV.

RE: Substitute El-34 for KT 88s and 120s, posted on October 21, 2014 at 08:00:33

AbeCollins
Audiophile

Posts: 46306
Location: USA
Joined: June 22, 2001
Contributor
Since: February 2, 2002

I've had EL34, KT90, and KT120 tubes in my integrated amp driving the Thiel CS2.4 speakers. The EL34s didn't cut it but that was due to insufficient power.

I need to go back to the EL34s and give them a try again since I'm driving the more efficient Tannoys but I have no issues with the KT120 sound. I love 'em and they're powerful.

I wanted to try KT150s but Rogue told me that I wouldn't get good results using them in the Cronus Magnum..... and they're rather pricey.

RE: Substitute El-34 for KT 88s and 120s, posted on October 21, 2014 at 09:42:49
BCR Audiophile Posts: 2446 Location: connecticut Joined: April 7, 2009	I've used both types with my Quicksilver amps. The KT88's have a bigger sound. It all depends on the speakers you're using. The EL34's are a little laid back in comparison. You should give them a try,they are very inexpensive compared to the 88's. BTW,I prefer the 34's with my Harbeths'.

RE: Substitute El-34 for KT 88s and 120s, posted on October 21, 2014 at 10:30:56
TGT Audiophile Posts: 531 Location: Kentucky Joined: December 6, 2002	I have no goal in mind just curiosity. I have seen some very good reviews of EL-34 based amps. Primaluna's newest integrated amp stock tube is the EL-34.

Rogue and ARC, posted on October 21, 2014 at 12:59:58
mbnx01 Audiophile Posts: 7956 Location: Eagle, Idaho Joined: October 22, 2004	Both switched over to KT120's after hearing them for awhile. That says quite a bit I think. 'A lie is halfway around the world before the truth gets its boots on'. -Mark Twain

Is the KT120 a direct swap for the KT88 ??, posted on October 21, 2014 at 15:50:57
ABliss Audiophile Posts: 1482 Joined: March 16, 2001 Contributor Since: August 3, 2002	no adjustments needed, except for rebias ? If so I may try a pair in my home brew.

RE: Substitute El-34 for KT 88s and 120s, posted on October 21, 2014 at 16:30:58

dirtyvinyl

I have the older PL Prologue2. Essentially the same but different.
Stock with KT88-nice.
With EL34-subtle decrease in both the upper hi frequencies and the lowest frequencies.

It's the mids that seem more "realistic" It's not a huge difference, but nicer to my ears.

Ended up with Genalex KT77's which offered another subtle nudge of "real"

The bass loss wasn't a deal breaker since I have an REL sub. As far as the loss in highs, it smoothed out the sometimes exaggerated highs of some music.

The triode mode of your amp may give you an idea of the drop in the high/low registers of the "EL34 sound"

Correction to my post, posted on October 21, 2014 at 17:03:12

dirtyvinyl

"I currently run KT 88s and KT 120s in my PrimaLuna Prologue Seven Monoblocks"

Oops! I misread the stats. I thought it was "Dialogue 7 amps. They have the triode/ultra linear switch.

Oh yeah, YMMV naturally.

RE: Substitute El-34 for KT 88s and 120s, posted on October 21, 2014 at 19:34:38

RGA
Reviewer

Posts: 15177
Location: Hong Kong
Joined: August 8, 2001

Generally I agree with Abe on the sound but I would suggest it depends on the amp. Years ago I directly A/B'd the Jolida 302B versus the Antique SOund Labs AQ1003DT both EL34 amps and they sounded entirely different. The Jolida was warm and thick and quite stereotypically tubey while the ASL was lean and crisp and more SS like.

I think most of these things come down to the other parts in the chain like the caps, transformers, wires, design, power supplies etc.

I suspect you could take EL34 amps from a variety of makers and they will each sound different enough that you could not likely conclude that EL34 sounds like "X" and KT 88 sounds like "Y" - The Jolida and the ASL used the same tubes and the sound was completely different. My Audio Space EL34 Mini-2SE is again different that both of those amps for around the same price.

Generally in the same company line up I have preferred the EL34 over the KT88 versions.

If your speakers are not ridiculously hard to drive I would definitely a good try an 845/211 SET in the 18+ watt range. None of the PP EL34/KT88/KT120s have been in the same class.

Further it's somewhat important not to stick with just one brand. Company A may make a nicer sounding EL34 than company B but company B may make a nicer sounding KT88 than company A.

RE: Substitute El-34 for KT 88s and 120s, posted on October 21, 2014 at 21:48:16
Daverz Audiophile Posts: 2104 Location: So. California Joined: September 24, 2002	I started out with KT90s in my Rogue M-180s before going to the KT120s, and I sometimes wonder what other power tubes would sound like.

RE: Is the KT120 a direct swap for the KT88 ??, posted on October 21, 2014 at 22:45:05
AbeCollins Audiophile Posts: 46306 Location: USA Joined: June 22, 2001 Contributor Since: February 2, 2002	I believe they are pin compatible but the KT120 might draw more filament current. The specs I saw via internet search showed KT88 nominal filament current as 1.6A. The KT120 spec I saw said 1.65A to 1.95A. If your filament transformer / supply is up to the task, it should work.

RE: Substitute El-34 for KT 88s and 120s, posted on October 23, 2014 at 09:26:12

garymuffley
Dealer

Posts: 445
Location: Maryland
Joined: March 29, 2006

The simple answer is there is no answer. You really have to try the tubes in your amp. Anyone who says that KT-120s, or KT-88s are better or worse than El-34s is deceiving themselves. Let me explain just a few factors that come into play. The plate-to-plate impedance of the output transformer strongly influences how a particular tube will work. The optimum impedance for a KT-88, KT-120 and El-34 are NOT the same. If you drop a KT-120 into an amp optimized for an El-34 and it doesn't sound as good, don't blame the KT-120. The other variable, of course, is that different makes of El-34s sound different from each other. The only way you can tell how it works in your system is the try the tubes you are considering.

RE: Substitute El-34 for KT 88s and 120s, posted on October 23, 2014 at 13:27:20
TGT Audiophile Posts: 531 Location: Kentucky Joined: December 6, 2002	My PrimaLuna amps have auto bias. Does that take care of the plate-to-plate impedance issue?

RE: Substitute El-34 for KT 88s and 120s, posted on October 24, 2014 at 06:31:43
garymuffley Dealer Posts: 445 Location: Maryland Joined: March 29, 2006	No. Auto-bias and plate-to-plate impedance of the putput transformer are two different things.

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Substitute El-34 for KT 88s and 120s

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