Eico HF-81 and ELNA Cerafines

[Chris Robinson]

My Wrights are back in Kent (WA) for a once-over by George Wright, so while they are gone, I put the Eico HF-81 back into duty.

I got an email from Kelly saying that Jean-Francois had been using the ELNA Cerafines (47uF/500V) and found them wonderful. He had heard a lot of positive comments about the Sprague Atoms (which I had in my -81) so he decided to try a pair. I said the sonic deterioration was quite noticable with the Spragues so he pulled them out and put the Cerafines back in.

This got me wondering if my -81 could actually sound BETTER, so I ordered a pair off of Angela.com. I received them on Friday and replaced the Atoms with them yesterday afternoon ...

After reinstalling into the system and booting up, I could hear an immediate difference, mostly in the bass. While the Spragues weren't "muddy", the ELNA's are much tighter, quicker and more accurate, pitch-wise. All of the lovely midrange and musicality is still present ... There seems to be more clarity there as well. J-F and Kelly, thanks for the heads up on this mod. It is sonically obvious.

I'm anticipating with another 50-100 hours of burn-in, the sound will only get better and smoother!

Just another data point for you Eico fans.

[NOSValves]

Interesting !! To bad they don't make the proper size multi section cans for all these amps. By the way the difference in bass response can be partially attributed to 20% higher value but its still within spec of the EZ-81 tube so why not ! Its funny because Kelly always said don't up this past 40uf because it will alter the sound of the amp in a bad way.

Craig

[Chris Robinson]

I'm thinking that the Spragues and ELNAs are a bit like apples and oranges. I liked the sound of the Spragues very much but think the ELNAs are one step better. They aren't cheap ($35/ea.) for sure.

The bass doesn't sound louder or out of balance with the rest of the music; it just sounds tighter and more refined. It's a subtle but obvious difference.

I don't know what other caps folks are using, but the mods you did to this Eico, along with the Telefunkens, really took the sound up to a very high level. It really approaches the Wright 2A3's but misses some of the articulation that the SET displays. A very nice, small integrated package, though, and particularly a nice combination with the Klipschorn.

Who would have thought?

[Deang]

Chris, I'm curious here about your description.

Is it that the Wright's are more 'articulate', which is a word I use to describe a systems ability to keep everything intact and free from congestion during complex passages -- or is it they have a higher degree of 'immediacy', in the sense of more low level detail resolving power -- like taking things normally layered deep in the music, and bringing it to the top?

The reason I ask is because based on my limited experience -- I would actually use the former to describe good push-pull, and the latter to describe SET.

[NOSValves]

Chris,

What your describing again is easily attributed to the added 20% reserve competance of the 47uf compared to 40uf ratings. This is exactly why I up the values on my personal amps even though it adds stress to the rectifiers. To do a honest comparison the same values are required to really make any assumptions.

There are many surprising intergrated amps out there. It never stops amazing me too !! You should hear the DeWald PP EL-84 I did not long ago it lacks bottom end but the mid and top are simply amazing ! Soundfield and black area around instruments galore. This amp had the worst looking output Iron I have ever seen. Looked very much like something out of a single ended console system.

Craig

[mike stehr]

Too bad Elna does not make the Cerafine PS caps anymore.

They would probably be a little less exspensive.

Sounds tempting.

[Chris Robinson]

"Is it that the Wright's are more 'articulate', which is a word I use to describe a systems ability to keep everything intact and free from congestion during complex passages --

or is it they have a higher degree of 'immediacy', in the sense of more low level detail resolving power -- like taking things normally layered deep in the music, and bringing it to the top?"

=================

Dean, I think we're on the same page here but my nomenclature is the reverse of yours. I think the Wrights in particular, or SET in general (I suppose), have, using your terminology, more "immediacy" in that they dig out motifs and passages that otherwise might not be noticed. They do this while keeping the whole complex music "package" together. I don't hear them getting "congested" during complex passages either, although I don't come anywhere near the rated power output of these flea-sized monoblocks. Some have commented that they start to "break up" as we push the volume into the 110db+ range. I rarely listen to music higher than 85-90db.

I suspect your terminology is correct but I'm new to describing amps and music. Articulation, to me, suggests the ability to "make clear" the smaller details in music, while "immediacy" suggests a presence to reproduced music that is "live" and "ubiquitous".

Words aside, both the Wrights and the Eico sound very similar to me musically now, although I think the nod for resolving ability goes to the Wrights. Let's wait until the Pantheon is in place for the final test. What comes out of an amp is only as good as what goes in ...

[mike stehr]

So 50 microfarad would the max amount of capacitance for a EZ-81/6CA4?

That's what the tube data for this particular rectifier claims.

I noticed the bass increase when I bumped up the capacitance 10 mics with the Sprague's from the stock 30 mfd.

[NOSValves]

Mike yup that is the Spec. But actually its near that when measured in stock form with the 30 MFD stock value. There is a effect that happens from all the caps south of the first stage that loads the first section. So running a full 50 on the first stage will actually be over the rated value although I think all would be well anyway.

Craig