Dilemma: Klipsch Cornwall IV vs Tannoy Kensington SE

[OzBrit Audio]

Mike, you should get some liquid nitrogen and cryogenically treat those EH valves

Seriously when I had my Woo Audio WA7 headphone amp I had about 6 different valves for it. The best by far was a gold pinned EH that had been cryogenically treated. The sound was so rich and detailed, it left all the others behind.

 

[Mike Hanson]

Mike, you should get some liquid nitrogen and cryogenically treat those EH valves

Seriously when I had my Woo Audio WA7 headphone amp I had about 6 different valves for it. The best by far was a gold pinned EH that had been cryogenically treated. The sound was so rich and detailed, it left all the others behind.

I don't know how much stock I place in cryogenic treatments. I do recognize how it affects the crystalline nature of copper, but I'm skeptical of whether it has an impact in the audio spectrum, and if so, whether the effect is long lasting. However, it's generally a relative inexpensive option, so I sometimes click the box, just for shits and giggles.

I was very happy with the EH Gold 6922 input tubes (non-cryo), although one of the prior 6922EH (non-gold) was creating a fair bit of hiss. With the new tubes, the hiss was gone and the clarityimproved notably.

The 6SN7 driver tubes are a very generic looking tube stating 6SN7GT "Made in China", and the accompanying boxes are white with no additional markings.

Consequently, I just purchased a reasonably priced pair of lightly used 6SN7 EH tubes (non-gold). Apparently the input tubes are more impactful to the sound, but I'll see if these driver tubes boost the performance over the no-name tubes that are there now. If so, then I might go for the EH Gold at some point.

I'm really in no rush, because the system still exceeds my expectations, bringing a smile to my face every time I give it a listen.

 

[OzBrit Audio]

I don't know how much stock I place in cryogenic treatments. I do recognize how it affects the crystalline nature of copper, but I'm skeptical of whether it has an impact in the audio spectrum, and if so, whether the effect is long lasting. However, it's generally a relative inexpensive option, so I sometimes click the box, just for shits and giggles.

I was very happy with the EH Gold 6922 input tubes (non-cryo), although one of the prior 6922EH (non-gold) was creating a fair bit of hiss. With the new tubes, the hiss was gone and the clarityimproved notably.

The 6SN7 driver tubes are a very generic looking tube stating 6SN7GT "Made in China", and the accompanying boxes are white with no additional markings.

Consequently, I just purchased a reasonably priced pair of lightly used 6SN7 EH tubes (non-gold). Apparently the input tubes are more impactful to the sound, but I'll see if these driver tubes boost the performance over the no-name tubes that are there now. If so, then I might go for the EH Gold at some point.

I'm really in no rush, because the system still exceeds my expectations, bringing a smile to my face every time I give it a listen.

I only have limited experience with tubes Mike but with the WA7 the gold pinned cryogenic EH far surpassed all the other valves by quite a margin. How much the cryogenic bit played I can't really say but the other valves I tried were all decent. So I suspect quite a bit.
Woo audio produce some excellent valve gear and it was their recommended valve for this amplifier.

On a different subject and noting our earlier conversation on the SE amplifiers and power supply sensitivity. I have just done a regulated front end for the SE200 and I am really pleased by the difference this has made. The increase in richness and dynamics is very noticeable. So yes these amps are sensitive to dirty power (and my mains is a good example of this - it causes me headaches for my digital front end, all work in progress here)

 

[Mike Hanson]

Back when I was determining how to proceed, I was receiving alternating bits of advice regarding the place for tubes in my setup:

• Most here on PFM insisted that a tube power amp (or integrated) was necessary, because it would be a better match for the Cornwall than my solid state amps. Damping factor was suggested as a major contributor, but the magic of tubes would also play a large part.
• A few here and elsewhere indicated that the power amp should be fine, but that a tube preamp would add the extra richness that I wanted. One fellow insisted that a tube pre-amp would let the soundstage information through, which would then be amplified by the solid state power amp. He also insisted that it would require a very expensive preamp to do this adequately. This seemed a bit woo-woo, but I try to keep an open mind.

I recently realized that the subwoofer output on the Cary SLI-100 integrated is a full-frequency output, which could be used to drive an external power amp. This would enable me to test the integrated in the SLI-100 with its power amp stage, and also to feed the tube pre-out into the Avondale SE230.

Having little faith in my ability to objectively compare things separated too much by time, I utilized a Douk Audio "ONE Little Bear" VU3 amp/speaker switching box:

The Cary had a higher gain than the SE230, so I had to tweak the volume with each switch.

So what did I learn?

• Both amps had excellent dynamics and PRAT.
• The SE230 sounded more solid and focused, with a quieter background. This makes sense, given SS amps tend to have less distortion than tubes.
• The Cary's power amp section evinced a bit of a shimmer, possibly due to the even order harmonics that are associated with tubes. This wasn't a bad thing, but somewhat unexpected. It made upper frequencies seem more noticeable, but I wouldn't say they were "louder".
• The most remarkable thing was the difference in the soundstage: It was unexpectedly stifled with the SS amp, whereas it utterly bloomed with the tubes.
  • This invalidated the claim of the fellow who insisted that a tube pre-amp with a SS amp would be best.
  • The SE230 has no problem creating in impressive soundstage with the others speakers I've tested (Vandersteen 3A, Royd RR3, Ergo IX, etc.), so it's something to do with it and the Cornwall.

So this experiment seems to have confirmed that the Cornwall creates the most magic with a tube power amp. I cannot say whether this is due to the damping factor, or something else.

Just to be thorough, I'm going to redo this test using my Neurochrome Modulus-686 power amp. This amp doesn't have as much PRAT as the SE230, but it's much cleaner and more controlled. Perhaps it will do a better job of passing along that soundstage information from the pre to the speaker.

One combination that I cannot test is a solid state pre-amp into a tube power amp, as I don't have the necessary gear. Some integrated amps have a "Home Theatre" input, which typically goes straight to the power amp section of an integrated, but the Cary SLI-100 doesn't have that feature.

So much fun, and so incredibly intriguing!

 

[anubisgrau]

and you havent even arrived to the cables yet

 

[Tony L]

Having little faith in my ability to objectively compare things separated too much by time, I utilized a Douk Audio "ONE Little Bear" VU3 amp/speaker switching box:

Does this box provide a load to the currently deselected amp? It is very risky indeed to run a valve amp without a loudspeaker load or a resistor emulation of one, you can easily end up cooking the output transformers.

PS I don’t know the Cary, but you’ll very likely find it is a power amp with a passive preamp. Most integrated valve amps are as it is just the most logical way to make one given modern 2V line sources. As such you very likely didn’t hear a valve preamp in your experiments!

 

[Mike Hanson]

Does this box provide a load to the currently deselected amp? It is very risky indeed to run a valve amp without a loudspeaker load or a resistor emulation of one, you can easily end up cooking the output transformers.

PS I don’t know the Cary, but you’ll very likely find it is a power amp with a passive preamp. Most integrated valve amps are as it is just the most logical way to make one given modern 2V line sources. As such you very likely didn’t hear a valve preamp in your experiments!

Well that certainly muddies the waters. I'll do some digging and see what I can find out.

 

[OzBrit Audio]

Back when I was determining how to proceed, I was receiving alternating bits of advice regarding the place for tubes in my setup:

• Most here on PFM insisted that a tube power amp (or integrated) was necessary, because it would be a better match for the Cornwall than my solid state amps. Damping factor was suggested as a major contributor, but the magic of tubes would also play a large part.
• A few here and elsewhere indicated that the power amp should be fine, but that a tube preamp would add the extra richness that I wanted. One fellow insisted that a tube pre-amp would let the soundstage information through, which would then be amplified by the solid state power amp. He also insisted that it would require a very expensive preamp to do this adequately. This seemed a bit woo-woo, but I try to keep an open mind.

I recently realized that the subwoofer output on the Cary SLI-100 integrated is a full-frequency output, which could be used to drive an external power amp. This would enable me to test the integrated in the SLI-100 with its power amp stage, and also to feed the tube pre-out into the Avondale SE230.

Having little faith in my ability to objectively compare things separated too much by time, I utilized a Douk Audio "ONE Little Bear" VU3 amp/speaker switching box:

The Cary had a higher gain than the SE230, so I had to tweak the volume with each switch.

So what did I learn?

• Both amps had excellent dynamics and PRAT.
• The SE230 sounded more solid and focused, with a quieter background. This makes sense, given SS amps tend to have less distortion than tubes.
• The Cary's power amp section evinced a bit of a shimmer, possibly due to the even order harmonics that are associated with tubes. This wasn't a bad thing, but somewhat unexpected. It made upper frequencies seem more noticeable, but I wouldn't say they were "louder".
• The most remarkable thing was the difference in the soundstage: It was unexpectedly stifled with the SS amp, whereas it utterly bloomed with the tubes.
  • This invalidated the claim of the fellow who insisted that a tube pre-amp with a SS amp would be best.
  • The SE230 has no problem creating in impressive soundstage with the others speakers I've tested (Vandersteen 3A, Royd RR3, Ergo IX, etc.), so it's something to do with it and the Cornwall.

So this experiment seems to have confirmed that the Cornwall creates the most magic with a tube power amp. I cannot say whether this is due to the damping factor, or something else.

Just to be thorough, I'm going to redo this test using my Neurochrome Modulus-686 power amp. This amp doesn't have as much PRAT as the SE230, but it's much cleaner and more controlled. Perhaps it will do a better job of passing along that soundstage information from the pre to the speaker.

One combination that I cannot test is a solid state pre-amp into a tube power amp, as I don't have the necessary gear. Some integrated amps have a "Home Theatre" input, which typically goes straight to the power amp section of an integrated, but the Cary SLI-100 doesn't have that feature.

So much fun, and so incredibly intriguing!

Interesting comparison Mike

I'm assuming the pre out on your Canary has had some valve amplification so indeed it does put to bed the idea that a valve pre would get the sound your looking for.

And still more curious that the SE230 doesn't soundstage so well through the Cornwalls but fine with everything else. Do you get the same experience when you cut out the Canary just in case the Canary pre out is colouring the sound in some way. An interesting test would be to do the same comparsion with another set of speakers ?

I like the box btw. I might invest in one for doing my amplifier comparisons. Pressing a remote is certainly the best way to do an AB comparison.

 

[OzBrit Audio]

Just read Tonys comments on the pre out. Maybe no valve amplification?

 

[OzBrit Audio]

Thinking about this the best way to do the amplifier comparisons would be be to build a simple splitter ( a couple of resistors should do the trick) for your DAC out that feeds one into the SE230 and other into the Canary. Thats assuming you can control the volume out from the DAC.

Then you know both amps are getting exactly the same signal input

 

[Mike Hanson]

Thinking about this the best way to do the amplifier comparisons would be be to build a simple splitter ( a couple of resistors should do the trick) for your DAC out that feeds one into the SE230 and other into the Canary. Thats assuming you can control the volume out from the DAC.

Then you know both amps are getting exactly the same signal input

I know what the SE230 sounds like fed directly from the T+A DAC200 (which does have a volume), as well as using fixed output from the T+A into a Benchmark HPA4 pre-amp (solid state). There's a lack of richness that started down this thread's quest in the first place.

According to the Cary SLI-100 manual, each channel has:

• 6922 Input Buffer Preamp
• 6SN7 Pre-Driver/Phase Inverter
• KT150 Output Tubes (pair)

There are two comments regarding the subwoofer output:

• [There is a ] Full range right and left channel output for connecting a powered subwoofer. May also be used to connect to an additional amplifier.
• The input signal from the volume control is direct coupled (DC) to the first grid of the 6922. .... The sub-woofer output is derived from the wiper of the volume control.

To me, this doesn't clarify whether the subwoofer output is actually after the 6922, or parallel to it. I'll send a message to Cary and ask.

 

[Yank]

The subwoofer output is before the 6922.

 

[shrink]

This sounds a bit like my journey with Harbeth SHL5+

When I first got them I was using a McIntosh 2275 valve, which is a distinctly un-valve sounding amp, and the whole thing was much as you describe your Cornwall’s, a touch thin, albeit with amazing PRAT, superb imaging and some phenomenal musicality.

So I gave up on the Harbeths and went for a pair of tannoy legacy Eatons, and much as you describe I found them warm to the point of coloured. This was actually my second pair of big tannoys and the third pair I’ve heard and every time I have the same complaint, a serious suck out in the presence region, and a deeply recessed upper midband that gets better with volume, but is hugely uninvolving at low volume.

After a lot of faffing, I ended up back with another pair of Harbeth SHL5+ as thinness aside they communicate music so very well.

But with perseverance I found a combination of kit that makes them sing, and now the idea of thin is far in the past, they now sound punchy, agile, dynamic and sometimes even gutsy!

It took a Luxman L509X to do it though!

 

[Tony L]

According to the Cary SLI-100 manual, each channel has:

• 6922 Input Buffer Preamp
• 6SN7 Pre-Driver/Phase Inverter
• KT150 Output Tubes (pair)

That is standard valve power amp design; same concept as my pair of 1950s TL12 Plus mono amps (EF86 input, ECC81 phase-splitter, 2xEL84 push-pull output and a GZ34 rectifier).

I bet the Cary “preamp” is just a passive volume knob and input selector, no different in practice to the Audio Synthesis passive attenuator I use with the Leaks. The combination of really high input impedance (1mOhm in the case of the Leaks) and high first stage gain means you really don’t want or need an active preamp with modern sources.

 

[Mike Hanson]

The subwoofer output is before the 6922.

I expect you're right, and I've sent a message to Cary for confirmation.

 

[OzBrit Audio]

I know what the SE230 sounds like fed directly from the T+A DAC200 (which does have a volume), as well as using fixed output from the T+A into a Benchmark HPA4 pre-amp (solid state). There's a lack of richness that started down this thread's quest in the first place.

According to the Cary SLI-100 manual, each channel has:

• 6922 Input Buffer Preamp
• 6SN7 Pre-Driver/Phase Inverter
• KT150 Output Tubes (pair)

There are two comments regarding the subwoofer output:

• [There is a ] Full range right and left channel output for connecting a powered subwoofer. May also be used to connect to an additional amplifier.
• The input signal from the volume control is direct coupled (DC) to the first grid of the 6922. .... The sub-woofer output is derived from the wiper of the volume control.

To me, this doesn't clarify whether the subwoofer output is actually after the 6922, or parallel to it. I'll send a message to Cary and ask.

Mike I still say if you're doing amplifier comparisons using a splitter is the way to go. You can't be sure your Canary pre out isn't changing the sound signature.

For example, I had a Schiit Saga unity gain pre amp that was switchable between passive and valve mode. In both modes the pre amp had a negative impact on SW both wrt sound stage and dynamics. Only when the valve was taken out of play did the pre amp have not noticeable affect on SQ (verified by another Saga user when I posted online).

Another benefit if you down this route is you can easily AB compare any two amps, for example your 230's and Modulus 686.

 

[OzBrit Audio]

That is standard valve power amp design; same concept as my pair of 1950s TL12 Plus mono amps (EF86 input, ECC81 phase-splitter, 2xEL84 push-pull output and a GZ34 rectifier).

I bet the Cary “preamp” is just a passive volume knob and input selector, no different in practice to the Audio Synthesis passive attenuator I use with the Leaks. The combination of really high input impedance (1mOhm in the case of the Leaks) and high first stage gain means you really don’t want or need an active preamp with modern sources.

Tony

Thats a lovely looking piece of equipment.

Did you have it restored to look like that. It must be near 70 years old by now?

 

[Tony L]

Thats a lovely looking piece of equipment.

Did you have it restored to look like that. It must be near 70 years old by now?

The paint is totally original. The hard bit was finding another of similar date in similar condition, but one turned up eventually! Full restoration thread here. They are superb little amps, it took me a long time to get there, learned a lot along the way, but I’m delighted with how they turned out. I’m not sure of their exact date, but they are the first case colour and circuit variation for the TL12 Plus, so between 1957 and 1960 or so. Very rare to see a genuinely good pair of them!

 

[OzBrit Audio]

They look great Tony

Given their reputation I would love a pair myself to renovate. Would be great as a yardstick comparison for my DIY solid state builds although I expect they in many areas they would be difficult to beat.

I'm sure even in poor condition their as rare as hens teeth though

 

[Mike Hanson]

I do have

Mike I still say if you're doing amplifier comparisons using a splitter is the way to go. You can't be sure your Canary pre out isn't changing the sound signature.

For example, I had a Schiit Saga unity gain pre amp that was switchable between passive and valve mode. In both modes the pre amp had a negative impact on SW both wrt sound stage and dynamics. Only when the valve was taken out of play did the pre amp have not noticeable affect on SQ (verified by another Saga user when I posted online).

Another benefit if you down this route is you can easily AB compare any two amps, for example your 230's and Modulus 686.

I'm always comparing things, and currently building a splitter. Check out my Output Selector thread in the DIY section.