I have about 50 hours on my ZROCK2 and it is hitting its stride with a wider and deeper soundstage (than when it was brand new (three days ago).

The tube Steve supplied is a red tip 5963 made in U.S.A. and Steve told me he found some special NOS tubes for the ZROCK.

I am curious what is the make of the tube that Steve supplied (it is a short plate gray with two long ribs and three cross ribs (like a double pane window). The "Window Pane" is flanked by two small rectangle holes aligned with the center cross rib.

Photos to follow

I have enjoyed tube rolling in the past, does anyone have any suggestions or should I just enjoy the tube Steve supplied for the 10,000 hours

Peter

Peter, thanks for weighing in. If you are enjoying the sound of that tube, keep using it for a while. It sounds as if it's a good one.

I'm interested in hearing more of your sonic impressions!

Thanks. It's a long wait for mine!

Back To The Mazda, tighter bass and clarity but a little boring

I found a RCA Command 5814A in my stash, it adds the bass punch that the Mazda was missing without the syrupy sound the supplied RCA 12au7,
a happy medium or blend between the two?

The last few components I have gotten from Steve have had red-tipped tubes, and NOT NOS so I believe Steve is red-tipping these tubes himself. . . .

Correction the 5814A RCA Command has a punchy Bass for Video, (perky?, Dynamic?).

Yes, once I have selected an ideal tube I red tip it to distinguish it from other tubes.  

The first thing I do is match the sections so that we have perfect channel balance.  

Then I check the harmonic distortion of each section to be sure it not only matches in total % but then also matches in harmonics.  Occasionally a tube (or tubes) will have an unexplained difference in each section on the 3rd or 4th or 5th harmonic.  

The tube is then run in and cycled a couple times to ensure stability.  

This series of tests not even the best tube tester can accomplish, so without these tests there is a certain degree of "unknown" with any tube.

We just want to start you off with the absolute best tubes possible so that you have a solid reference to compare with when or if you roll tubes.

Steve

CORRECTION:

The tube I sent back was a 1970 BRIMAR CV491, not a CV429 I referred to in previous posts


Peter

Photo Of Brimar CV 4003/12au7

My new ZROCK2 arrives some time today! Can't wait.

colord - Nice! Mine is scheduled to arrive this coming Monday!!!!!

Well, I've some hum too, just as I had hum with a CSP2+ for a long time, I can definitely hear it near the speaker but not at all at the listening position.

It took me a while with the CSP2+ but I finally found that paying attention to cable placement cleared up the hum for me. Now in this home and set up it is harder to get behind and reroute cables so I haven't yet done so, but I'm pretty sure in my case that would cure it. Even though I use shielded cables at some point hum comes in. . . .I'll separate power and interconnects as much as I can and I bet mine goes away. Hope it's as simple as that for you. (What I have now doesn't really effect the sound for me, and no hum at all when I use the ZROCK2 to feed the Taboo Mk IV, so it's cabling around the Torii is my guess.)

Hi Lon.....  Yes, I tried the rerouting that you suggest, separating power and signal cables, different cables, etc.  My hum is in both channels and Very Audible from my listening position.  And, as mentioned, increases directly with the EQ increase.  It is virtually not there when the EQ is bypassed or turned below 12:00 o'clock.....and unchanged even with the inputs unplugged. Conclusion: it's coming from somewhere in the EQ circuitry.  

Well, two weeks in and I'm back to using the tube that Steve supplied. It has a great balance of tonal fullness and a bit of lushness that no other tube I've rolled so far can match. I think it might become stuck in the ZROCK2. . . .

Just sent my original ZROCK to Steve yesterday to be updated to the New version and also add silver RCA's. Interested to see what the difference will be. He should have it there by Monday.

calord

I haven't noticed any hum with the zrock. sorry to hear you are experiencing hum. I know Steve will get back to you to trouble shoot the problem as soon possible. Nonetheless, I know it is frustrating.

Tal

Those can be some pretty darned good tubes. I used a Conn labeled version in my ZP3 for a while, and it is pretty nice in the ZROCK2 as well, though I can't keep Amperex out of the ZROCK2--I have a Bugle Boy Holland in right now. Just the right texture and tone for my system.

I too am waiting as patiently as I can for the fully modified ZROCK2 I ordered. Especially as in about 6 weeks I'll be setting up a second system and will want to use a ZROCK2 in that, and will have two when this new one arrives.

So HK, how’d the 5814A’s with the windmill getter sound. I’ve been thinking of buying that tube. Seems a little pricey for the ones i’ve found.

I haven't tried a "windmill getter" 5814A but I have tried a GE gray plate and an RCA black plate and they are excellent tubes for the ZROCK2. I like the RCA a bit more, just the right touch of warmth.

I really have two different complements of tubes that make two different wonderful amps out of my SE84UFO3 25th Anniversary mono blocks, and the difference is really voltage regulation tubes in the amps for the output tubes, and the tube in the ZROCK2. One great amp is using old RCA 0A3 in the amps and the Amperex 6085 in the ZROCK2, this is a showstopper combo--great recordings have all the audiophile qualities and really shine. But lesser recordings don't fare as well. The other amp that is kinder to most recordings and gets used more often as I listen more to mediocre recordings than fantastic ones is using a pair of Arcturus 0B3 in the amps and the RCA 5814A in the ZROCK2. This has a little touch of forgiveness and warmth that makes it my every day combo.

Lately I've reconfigured all the input tubes in my signal chain but the ZROCK2 to GE 5670W with converters. And I really enjoy the resulting sound--neutral, with more back to front depth than ever before. I rolled rectifiers and regulation tubes (for the output tubes, the regulation tubes for the input tubes are inside the amps and I haven't felt like taking them down and apart recently) and I keep coming back to the Sophia Electric Aqua 274B--they have a great synergy with the 5670Ws--and the oldest pair of Sylvania 0B3 I have found, which took a while to bloom but have become fine tubes.

So with all that squared away between ZTPRE and 25th Anniversary modded SE84UFO3 Monoblocks, it was time to experiment with tubes for the ZROCK2.

I really like an Amperex 5814A that I have had in the component for a while, but with the 5670W they are just a little too. . . clinical? that may be the best word. I tried a Raytheon 5814A with an angled D getter that is a very nice tube but the one I received is quite microphonic and when it settled in occasionally it goes into a hissy fit; I have another example of this same tube on the way to me. In the meantime I found I had a Brimar CV 4003 that PK mentions enjoying above. It gives a fullness to the instrumental imaging and brings my digital a step closer to an analog sound. It is hard to take out of right now! I did get in a trio of RCA Command 5814A to try but I've resisted trying one so far. I did put one in my original ZROCK2 in the audio/video system, and it sounds very good, replacing an Amperex 6085 there that also sounds very good. That system is in a bigger, great "sonically" room and also is using different preamp and amp (CSP3 and Taboo Mk IV, both with the Anniversary mods). I'll try to resist popping the RCAs in the ZROCK2 in the main system for a bit more, I'm so enjoying the sound with the Brimar!

I'm curious as to why the 5963 tube is considered "special" , since this was originally developed for computer applications. Seems to me there are vastly superior options, many of which have been noted in this thread.

Been organizing my tubes as a project. Here is most of my "overflow" . . . .

Yes, I have one more tackle box full and a few smaller boxes that I keep near the amps to roll. I have 20 pair of the output tubes for the amps. . . that's probably a lifetime supply, especially as for the Monoblocks I order pairs from Steve once a year or so!

It's amazing what a tube change does in the ZROCK2. Three years in now and I'm pretty famiiar with this game-changing component, but it still surprises me sometimes.

In my main system I find the most "volatile" components as far as tube-rolling go to be the ZTPRE and the ZROCK2. I think it's just the way that the system is configured that makes them so prominent sonically. I have narrowed all my choices down lately to two sets of tubes for the ZTPRE and correspondingly two input tubes for the ZROCK2. I either use Amperex 6085 with converters to 6922 for the ZTPRE or a six pack of 6N5P. When I use the 6085 I get best results with a 6085 in the ZROCK2, and when I use the 6N5P in the ZROCK2 I use an Amperex (labeled Hewlett Packard) 12AU7 which like Goldilock's porrige is "just right."

I love the sound either of these set ups offer to the system; I think I'll leave the 6N5P in for a while and use the 6085 with converters in my audio/visual system downstairs when I set that back up next week (it's been out of use for two months due to repair and remodeling of the living room).