Tír Na HiFi

Actually I've noticed that on one of the valves there is a slight discolouration inside the glass like a black oxidation. Its near the bottom on the front side of the valve but small. The valve is still on and has the same uniform orange glow that the rest of them have, no differences between all 4. I've only noticed now cos I'm viewing the amp from a different angle since the room rearrangment. A sign that the valve is blown or on the way out? For those with experiences of this type of thing before what exactly did you notice in sound when your valves were on the way out?
Bias reading is ok for all 4.

No, most likely that's OK. Does it line up with a hole in the black plates inside the valve? You may also sometimes see a blue glow - that's OK too.


The glow is from the heater filament inside - bears no relation to whether the valve is going or not (it does need to glow though!). If the bias is OK though on the meter, then all that is OK I'd say.

Could I suggest something for you to try. Could you find a piece of soft flat foam. The kind of soft foam you might see around better packed electronics, about 6mm thick. Cut a small piece about 3" square, then cut a hole in the middle a little bigger than your tweeter. Then fix that piece around the tweeter. I've seen it done a few times and it lessens off-axis diffractions from the tweeter and might just ameliorate the problem.





Obviously you want to use something to hold it on that won't marr the speaker etc etc. Maybe its not even possible with the way your tweeters are set up....


Fran

DaveF wrote: I'm not sure if 'brightness' is the correct term to use. Its not searing or painful or anything like that. If you've ever done one of those speaker tests on and AV receiver where it deliberately puts the sound out of phase, it kinda sounds like that a bit, not to that extreme obviously. Its more of a resonance in the ear. Maybe some would call it treble harshness. If anyone wants to drop in and listen feel free to do so as I'd like another opinion.

I think I know the sound you mean, and for a long time I was very sensitive to it and always blamed the hifi. However, if it's the sound I'm thinking of, I've heard it at live concerts too... :)

I would look at the toe-in angle of the speakers, Dave. My Spendors are not what you call bright speakers, but if I toe them in towards me the sound hardens. They sound best firing straight down the room. Perhaps, in your case, some small experimentation with toe-out might be required. With regards to the cables, although Nordost cables are on the lean side, they are not bright. However, it is possible that they may not be the right synergistic fit for your system. See if you can borrow some Kubala-Sosna Emotions. Also investigate the spacing between the speakers as well as the distance between the speakers and your listening position, and also the spacing between your listening position and the back wall. Finally, although this may not affect the brightness issue, I think that your Ushers should be supported by Cerabases. According to the Finite Elemente website, Ceraballs are designed to support speakers weighing up to 40 kg, whereas Cerabases are capable of supporting speakers as heavy as 500kg. I have four of them under my FE Master Reference rack and they work a charm.

I see that you have these speakers up for sale in the For Sale forum. It seems a shame to rush into a sale and to price them aggressively for a quick sale. The Ushers are very fine speakers and warrant further investigation into how exactly they interact with your room and your amp before committing to a sale. It can be very frustrating working on alleviating system setup issues when what you really want to do is sit back and enjoy the music. However, it can be time very well spent. Replacing the speakers is an easy but very expensive option (especially when you factor in the recent expense of your Air-Tight) and should be considered a last resort. Even if you have your heart set on the Kharmas, take your time with the sale of the Ushers and don't sell them on for less than their true worth.

I would have to agree with Paul's considered comments. In the heat of the moment you can be lead down a blind alley especially when it comes to hi fi matters. Slow down Dave and take a big step back; There's a lot of sense in Paul's advice......

Thanks for your comments Paul but I've pretty much already exhausted all of the options you have mentioned. Changing interconnects made no difference, I toed out the speakers: didnt really change much, Rearranged the room and speaker positions entirely: didnt change anything. Used the speakers with and without the ceraballs: didnt change anything.

When you add it all up, the problem is soley between the Airtight and Ushers. I havent changed speaker cable so its one thing to try out but I dont believe that there are much differences between speakers cables if any at all. The Nordost Super Flatline that Im using is an all copper cable so it should be fairly neutral.

As good as the Ushers are, they were never keepers for me. Something along the lines of Kharmas or similarly voiced speakers are what I want.

I must stress that the sound is far from bad. This kinda 'ear resonance' (or brightness??) only exists on some recordings but it is an issue that I cant live with nonetheless.

Ivan Cloney is back the week after next so hopefully he might have some ideas or recommendations.

It certainly sounds like you've tried pretty much everything, Dave. If you intend to re-build your system from the amplifier outwards, then it make sense to choose speakers that were voiced with that amplifier (or similar). I believe that Kharma used Air-Tight (as well as Lamm) extensively during the development of the CRM 3.2 FE, so it would appear to be the ideal match. (By the way, if you ever win the Lotto, the Tenor amps are, apparently, a match made in heaven with Kharma). The pre-owned Kharmas that Cloney Audio have been selling for the past while are absolute bargains at €6400, which is a much sweeter pill to swallow than the RRP of the CRM 3.2's replacements, the Elegance db7 (around €20K). It's vitally important, though, to hear the Kharmas in your room, driven by the Air-Tight, playing your music, before you commit to a purchase. Happy listening, Dave. Having been through some pretty significant hi-fi upgrades recently, I can understand all too well just how exciting this must be.

After a couple of months of frustration I pretty certain now that I solved the treble issue here. Turns out that there was nothing wrong with the Ushers or the Airtight, it was the sources all along, the Wadia and my TT.
I tried all sorts of cables, changing around the room etc but none of them made one bit of difference. I was convinced that it was coming from the system itself and not from any room interaction. I even brought in a pair of Kharma speakers on trial too but the problem still existed which had me concerned greatly as Kharmas are supposed to be a great match with Airtight. All my attention was focused on the Amp-Speaker interaction.

Last week Fran came along with his EL34 and 211 valve amps. The EL34 amp added a tad more warmth but the treble resonance/ringing was still there in some recordings. The only thing left to try was a different CDP as it was pretty much my last hope. Here I was with a bunch of expensive equipment and none of it was gelling like it was supposed to.

Well yesterday I borrowed a Meridian G07 CDP from another forum member and immediately I noticed a more relaxed presentation and the to my delight the treble resonance was gone completely. No detail sacrificed either and for the first in a few months, today I was able to throw recordings at it without fear of wondering what I was going to hear.

This episode has taught me more than anything on how important synergy is in the system. With my older Gamut amp, the Wadia sounded great. But with the Airtight amp, the sound was pitched up in tone and often with a nasty resonance in the treble in some recordings. With the Meridian, that balance has been readdressed. So it looks like I need a much smoother sounding player as the Kharmas and Airtight are very very revealing.

I'm going to go ahead with the Kharmas as they've been on my wish list for a very long time. I just need to sort out a final solution for the CDP and the TT.

Good news Dave....at least you have identified the problem at last and you can now go about doing something to resolve it. It will be interesting to see what you eventually end up with!

Cheers Fergus.
I'm actually really liking this Meridian player and the owner wants to buy my Ushers too but he needs to wait a while before he can do so. :-)
I thinking that a Lector CDP7 might be a perfect match for my system now. I might also have made a mistake in trading in my Opus 21 for the Wadia earlier in the year but it soundwise it seemed like the right thing at the time.