Oh! For the love of tubes!

[Big Dog RJ]

G'day maties, greetings from down unda. We're currently sitting at 3C although it feels like 1C in Melbourne. The footy finals are on and then there's the NRL Rugby league 1/4 finals going on... the Melb Storm lost to the Broncos! Badly 26 to zero damn! Massive crowd at the footy, over 90 thousand in attendance.

So then to lift the mood a bit, I powered up the audio gear for some fine tunes. The tooones were fine after about an hour until I realised a rustling/ woosh noise coming from the left channel. At first I thought must be the left CLX mids&highs panel, since that's where this particular noise was emanating from. So I gave the panel a darn good vacuum thinking maybe that silly cat fur... but to no avail. Powered up again, the noise was still there.

Then I noticed, when I powered off the left monoblock, the noise goes off! Ah! It's a tooob. Now which bloody tooob...?so the investigation commences... turned out to be that little bugger- the Input tube: Mullard M8080 / CV4058.
I had plenty of spares, so no issues, just a two minute shut down - replace and power up and all goody!

I wanted to note though that this time round, it wasn't a tube failure as such, rather an annoying noise which I guess leads to failure. Or perhaps non-listenable. Maybe this particular tooob may sound fine in another device, I don't know.
However, in my past experience wherever one of these M8080's go bad, they usually emit a sort of raspy / paper tearing / popping noises. This rustling or whooshing noise was something quite different, hence why it took me a while to diagnose. Usually I'd pick out the naughty tooob instantly!

This is the same type of Mullards M8080 tubes that are used in the PV14, PV15, Classic/se Preamp, and also in the ART series 1 monoblocks (same amplifiers that Admin has). So for owners of CJ gear that use this particular tube, just letting you know that the types of noises aren't consistent as to what I've experienced.

Other than that, everything else is tickety boo and tunes are playing mighty fine!
Cheers, RJ

[admin]

Glad it was just an input tube. Those are inexpensive to replace. I have had tubes blow, bang!, and some that slowly degraded in sound quality.

I rather have an input tube slowly go than a big failure and fuse being blown. Had slow degradation with my previous PV-12L as well as my new PV-14L (which came with a bad tube and was making a hissing sound). And then I had a KT120 blow in my ART monoblock that took the fuse with it.

These failures are never fun and sometimes anxiety provoking but part of having tube gear.

Again, glad it was just an easily replaceable input tube.

[roberto]

Hola Chicos,

Last night I had the left channel with a truly rare, peculiar, unsteady behavior of one power KT'120. It was located at the front of the amp. The LED bias started to blinking on one tube, and then I did try to adjust it with no luck...then I saw another tube just behind it, with the top getting white. This told me that this tube was getting air inside and this is the bad tube. Turned the amp immediately off and got a fresh KT'120 there. Turned the amp on, waited to have the LEDs adjusted on both tubes, and problem was solved. The tube on the white color turned all white in less than a minute once it was replaced.

The funny thing was that the left channel had less dynamics and was not singing right as the right channel...so, I went to have a look to the amp, and that was the problem. A KT120 blown.

It is such a pleasure to listen the power amp back as it should. This amp drives my CLXs with authority and with a big super sound presentation. Really, Conrad Johnson sounds right!

Happy listening!

[admin]

Glad it is working. My last KT120 was a big pop with a fuse blown! I always worry about those. You did better than I to catch it before catastrophic failure like mine.

Now I just wish the tube prices would come down as those KT120's are expensive. But comrade Putin doesn't seem to be giving up on his conquest so I think we are going to be in a pickle for some time.

[roberto]

Well, I have some in stock. I was lucky to get the Cstock just at the beginning. The price was very low if I do the comparison. Also bought some Genalex Gold Lion 6922 too. This Genalex is not a bad sounding tube, I do know that there are other brands offering better sound. OTOH I am very happy with the results in my system. I really like the sound quality that I am getting...really love it. I have some time with my Classic One Twenty SE power amp, and only four Tung Sol KT120s tubes had failed over this 7 years or so.

Happy listening!

[Big Dog RJ]

Robbo mate,

That definitely sounds like the glass envelope of the bad KT120, most probably a hairline crack. For any tube to go whitish inside means that it has lost its vacuum, so air has crept inside.

If you are to look closely at that bad KT120, you'll notice a very fine crack somewhere... most probably on the top side. Seems like something must have accidentally struck the tube and caused this crack. That's why it's sometimes a safe idea to have that tube cage placed on when not in use.

I've had quite a number of tube maintenance issues. One in particular was actually on an ART150. When the item arrived in packing, one KT150 was already white, so no good. Another one looked a bit odd, such that there was a fine hairline crack on the top side of the glass. It hadn't turned fully white as yet but decided not to power up the amplifier until these two tubes were replaced. Worse case scenario, it would've blown out the B+ / plate fuses. Since lately these large value ceramic type fuses have gone up in cost. Damn, everything is really pricey now!

Very glad to hear that you managed to identify which Output tube it was. Something that comes through experience.

No matter all the fuss and muss, once these beautiful CJ amplifiers are up to spec, they do deliver a glorious sound.
Oh, for the love of tubes.

Woof! RJ

[Big Dog RJ]

Attn Admin:

We have quite a bit of drama down unda at the moment, with regards to tube suppliers. Basically, most are out of stock! The more common ones, EL34's, 6550's, KT88's, and the 12A series are still available. However, it's the KT120, KT150, 6N30P and 6922 equivalents that are out and if any of our suppliers happen to have any stock, pricing is generally 3 to 4 times more than what it was. For example, a matched set of quad KT120's were around $800. Now, this same tube supplier is charging around $2800 for a quad set. That's just nuts! Plus there's a wait time of several months!

So, what I decided is to use the other equivalents that can be safely used with no issues: KT88, 6550C or KT90. I've tried all of these types on my monoblocks, no issues. They all sounded quite different in their own way and yet very musical. I certainly do prefer the KT120 but if prices are going haywire, there are other alternatives.

Also don't compromise on the brand and make. Always get the best you can afford, otherwise overall performance of the amplifiers will diminish. Definitely don't want that!

Cheers, and enjoy those fine tunes!
RJ

[admin]

RJ,
That's some crazy prices. Can you import them from the US? I know you may have to pay a pretty penny for shipping but at $2800 for a quad set, it can't be that much (it would probably be under $700 for 4 KT120s).

[Joe Appierto]

I'm not sure if RJ meant USD 2800 or AUD 2800 which would be almost USD 1800. But even if the latter, that's frickin' outrageous.

EDIT: I just checked and Kevin at Upscale although he is limiting sales to Primaluna customers has them at USD $100 each. Tube Depot, other than a 10 tube limit per order, has them USD $130 each.

I realize that there may be some kind of premium being charged for shipment to Australia (why that might be is a different matter) but there's a difference between a premium and out and out highway robbery.

[admin]

Yeah, tariffs/customs fees can be high, but it's not going to triple the price. Either way this is a terrible situation. To think that less than 2 years ago I was buying KT120 for $40 a piece

[Big Dog RJ]

Yes, that was quoted a few months ago in AUD. I just checked their prices on the website, currently going at: $300.00 each per KT120.
Matched quad set for $1200.00 or a matched pair for $600.00 (TungSol KT120). Seems like they've dropped slightly from 2800... but still this is quite exorbitant. Looks like stock was delayed or something and has now arrived because this was definitely not the case earlier this year.
The last time I ordered a full suit of two quad sets of KT120's was charged at $800 (AUD). This was for a total of eight KT120's ($100 each). Now, we're looking at $300 each!!! And prices aren't getting any better, nothing is.

Importing small signal tubes is ok as long as their packed well. However, with the larger Output tubes, I never take that risk of damages during shipping and handling and end up with damaged tubes, as was the case with the ART150 (two damaged output tubes). Plus the suppliers don't refund now or give free of charge replacements, no chance. It's a doggy's world out there now... definitely not the case 20yrs ago. Ed or LJ would send across any tube that was damaged, no questions asked. Eve Anne Manley (Manley Labs) and Luke Manley (VTL) would also send stuff if damaged. Eve Anne's customer service was tops! She was the best at her game during that time, tremendous support. I'm not sure what their like now because I don't use Manley or VTL gear any more. However, in time to come I will change over to SS. As you can see the reasons why.

Pricing on the KT150 is currently sitting at $360 each, $800 for a just a matched pair, and $1600 for a quad set. Talk about exorbitant... I wonder if these tubes come with cake? or perhaps gold plated cookies.

Oh! for the love of tooobs.
cheers, RJ

[admin]

It's just crazy. I wonder if the factories in Russia are stockpiling and we will see a massive flood of tubes when this stupid war is over or did they just shut down production? Time will tell.

[roberto]

I really hope for the best of the world, that this nonsense war will end soon. It looks like Mr Putin is not doing very well, but this man has a lot of cards under his sleeve. War is not a good thing. I am always thinking why these crazy people don't go to the front to fight. They are always behind as far as they can be from the combat. Many innocent people are killed on both ways.
I hope too that the Russian people will wake-up against the Kremlin and Putin. This will stop this stupid war.

If I am offending someone with my way to think, please I beg for your understanding. It is just that we, the Costa Rican countrymen, believe in peace. We have no army. Talking is the way to solve our problems.

Please excuse my dare to say all this.

[Big Dog RJ]

Well said Robbo mate!

In fact believing in peace is one of the greatest assets any one could have, and also fine music! Most of those idiots fighting wars or causing wars simply don't believe in peace nor do they enjoy the music! That's why they're bonkers.

The Russian music scene extends far beyond the norm. It has a very rich history expanding to the Russian ballet and fantastic classical music. If donkey kong Putin could only appreciate this more, none of this nonsense would've ever happened. Just because of one man's madness the whole world has to suffer. And our precious tubes!

[Big Dog RJ]

Oh, BTW maties, not sure if anyone noticed that CJ just phased out the TEA1 phonostage. There's a new ART phonostage coming and I bet it's going to be right up there with the very best of bestest.

The TEA2 series is still going, not sure for how long though. Both these units are based on Class A circuits. Whenever my techie has a look at these, he's always very impressed with their Class A circuitry. It's at the highest level on all CJ gear.

Woofty woof'n! Enjoy those finest tunes.
RJ

[admin]

Somebody should send Mr. Putin a full ART series of CJ equipment, maybe he would realize that his time would be better spent enjoying music than carrying out a failed invasion.

[Big Dog RJ]

Good one Admin mate!

Just came across this, what the... priced at $1500 a pair, supposed to be an introductory offer... never heard of this brand until now. Talk about exorbitant!!! Plus plus.

Some make called AGD Productions
GaNTube 88MkIII whatever, supposed to be very high tech.

[roberto]

That's a very interesting new way to build tubes! I can see the reason why they are so expensive. I hope they sound as good as they look.

Great pic RJ!

I think that you are not going to believe what I can do right now in my system. I have the sexted Room Acoustics Tuning by Shun Mook. I have the singer or the main instrument in front of me, and behind the speakers, I have all the rest musicians, but still have depth and sense of 3D of them too. I can move the singer or the main artist back and forth at right the distance where I want to have the listening.

My friends can not believe this effect. It is amazing.

[roberto]

The problem is that this effect is only for one person seating in the sweet spot. If you move a little bit, the effect is lost. The tone and harmonic texture do not change.

What it is truly funny, is to see the face of the listener. What funny face expression they get...truly funny.

[admin]

Ah, the solid state tube. I've seen these around. Schiit has them as an option for some of their tube based units but really I never understood why anybody would want to go this way? You build a fully analog audio circuit and then convert it to digital half way through? Why not just build it SS in the first place.

The schiit ones are a much more reasonable price (although not output tubes like the one in the above picture: https://www.schiit.com/products/lisst