The following is meant to provide some feedback on the new Torii MK4 and on my (input) tube-rolling attempts.

I finally burned in my Torii MK4 for 100+ hours.
So, IMHO, the sonics have stabilised enough for me to report on my tube-rolling attempts.

My Audio Chain consists of

Oppo BDP 95
-> Soundsilver Symmetry Interconnects
-> Torii MK 4
-> Clearday Double Shotgun Speaker Cables
-> Alesis Monitor One Mk2 (Passive) Speakers (TEC 1994 Winner)

Tubes Used (Kept Constant during input tube-rolling)

Rectifier : Brimar 5R4GY "D' Getter
VR Tubes : RCA 0A3 "D" Getter,
                RCA 0C2 "0" Getter (any "D" getter versions out there???)
Output Tubes : GEC KT66 Gray Glass "D" Getter

Observations
1. The Torii MK4 is very transparent.
I also have a SE based EL34 tube amp (6 Moons Realisation award winner) which is also very clear sonically.
Both have the same resolution so Steve did not "BS" us when he made the bold claim that the PP Torii MK3 (and now 4) amp has the transparency of an SET based amp.

2. Because of the sonic transparency, in my system, the "best" sounding input tube would therefore be a "warm" one.
I rolled the following input tubes

(a) Philips (Holland) E88CC SQ Gray Shields "O" Getter
(b) Telefunken E88CC <> "O" Getter" Gray Shields
(c) Lorenz Stuttgart 3 Mica CCa "O" Getter Gray Shields
(d) Mullard (Holland) PCC88 Pinched Waist "D" Getter Gray Shields

No major surprises, the best sounding is the Pinched Waist, (d) above.

Tube (a) Had a nice touch of tube warmth but was not warm enough in my audio chain.

Tube (b) Had wonderful mids (and presence) but the bass was really lacking

Tube (c) Turned my Torii MK4 into the "Mystery amp"
High Resolution (HD Tracks) FLAC files sounded fantastic.
Low res Redbook CD FLAC were sonically atrocious.
If I lived on only High Resolution FLAC files, this would be my ticket.

Tube (d) Is the "Best" because it retained the sonic strengths of (a) to (c) whilst it overcame all the various shortcomings the above-mentioned tubes.

The Pinched Waist had
(i) More tube warmth than (a)
(ii) Had the glorious mids of (b) but was not lacking in the bass department
(iii) Was more forgiving than (c) above.
My low res sonic files did not sound like crap.
In fact, they sounded so good and non-fatiguing, I listened to low res files until 4 in the morning during one of my sessions.

Input Tube Recommendations (and musings)
My audio chain consists of pure silver interconnects and speaker cables so a warm input tube sounds best.
Any other CCa (e.g. Siemens) type of tube is likely to create an overdose of sonic transparency.

3. The Torii MK3 was built based on EL34 tubes.
On the new Torii Mk4, if you use a fat coke bottle rectifier (e.g. 5U4G or 5R4G) and 2 of those fat bottle output tubes (e.g. KT66), during installation, the tubes are likely to "say cheers" to one another!
After installation, the ventilation gap was only around 1-2 cm.
I hope this does not affect the tube life of my NOS tubes, I would have preferred a ventilation gap of at least 1 inch.

4. Sonic Depth and Width
The Torii MK4 has very good sonic depth and width.
The input tube also plays a part in affecting the size of the soundstage.

5. Positive Feedback Switch
My speakers did not whistle so it is compatible with this feature.
In my system, when the switch is turned on, it seemed to cause an expansion of the soundstage by at least 2 fold.
However, the sonics were more diffused and I preferred to leave the switch turned off (permanently).

6. Bass Switch
Bass was over boomy if I turned it on, so I left it in the "off" position (permanently).

7. Treble Switch
I left it (permanently) in the middle position cause it sounds wonderful to me.
Did not really experiment with this.

8. Volume Knob
With my current tubes, and my 88db speakers, I never have to turn the volume beyond the half-way mark.

9. Speaker Impedance (aka Epilogue)
This is a caveat to the above.
My Torii MK4 was built with 8 - 16 Ohms speaker taps.

However, despite the fact that
(a) there is a speaker impedance mismatch
(b) my speakers have cross-overs

The 8 Ohms tap sounds so good when paired with my current 4 Ohms speakers (with cross-overs!!!) that I'm seriously thinking of abandoning my original plan to use the amp with the 16 Ohms Zu Soul Superflys.

Hi Scott,

I've been using only the GEC KT66 in my Torii MK4 since the very beginning.

The reasons are due to the following below.

I learnt a very expensive lesson from tube-rolling various NOS EL34s ( on my non Decware SE EL34 amp) and 6DJ8 tubes (on my CSP2+).

For the EL34s, I started out with Mullard Xf2s ( and Other Mullard variants ) and then rolled Amperex "D" getters and finally the metal base philips EL34s.

Likewise for 6DJ8 tubes, I spent a minor fortune playing with almost all the various makes of tubes mentioned in Joe's tube lore and other exotic tubes such as Tungram, Teslas, Russian and Lorenz Stuttgart tubes.

My conclusion is that, most of the time, conventional wisdom applies when it comes to NOS tubes.
If I had just bought a pair of Pinched Waist 6922s or Metal Base EL34s in the very beginning, I would have saved myself a lot of $$$$ in the process.

So when Steve announced that KT66 tubes work better than EL34s, I decided to just get a Quad ( I got 2) of GEC Gray Glass NOS tubes and be done with the tube rolling.

For the rectifier, I also decided to tap on the experience of another tube roller.
He concluded that the Brimar 5R4 rectifier ranks alongside the famous GEC U52 rectifier.
I carried out a simple 5R4 rectifier shootout myself and found the Philips 5R4GYS to be a very good rectifier too BTW.

So some lessons I learnt from tube-rolling are:

1. Always get the "best" NOS tubes at the start
Coz it will work out to be much cheaper in the long run

2. Input tube sensitivity
The Torii MK4 is very sensitive to tube rolling.
By keeping other tubes constant, a Torii MK4 owner should be able to get the required sound he likes or requires just by changing the input tube.

I think this applies to just about any other Decware amp (e.g. CSP3) due to the inherent simple design.
The stock tube configuration should be good enough for most audiophiles but Decware amps will scale upwards sonically if one uses better NOS tubes.

3. Tuberolling can still spring surprises too
This seems to be a contradiction but I've found the Siemens E288CC to work exceptionally well in my CSP2+ and CSP3.
This is despite the bashing from Joe's tube lore.
So despite my current disposition on tube-rolling ( or lack of), I would still encourage anyone to tube-roll, but only if their budget allows for it.

I also sincerely hope that other fellow Decware fans will share their tube rolling experiences.

Lord Soth,  I did a little research this morning and can't find the Mullard PCC88s.  Where do you get these?  I have good results buying from Tube Depot or Upscale Audio and they don't show these.

Scott

If one was on a budget, couldn't upgrade all their tubes at once, or is just a cheap bastard like me, would you recommend putting your money more into NOS input tubes or better output tubes?  Where's the best bang for the buck, or are gains worth the money regardless of where spent?

The Philips 5R4GYS Rectifier for about $50 ea from Upscale Audio is highly recommended as one of those best bang for buck upgrades.

Steve mentioned that the gain of the input tubes for the MK4 was increased over the MK3. So any investment in the input tubes will be worth it,I.e. The MK4 is very responsive to input tube rolling.

Never tried the 5R4 type in the Torii. . . saw a pair of RCA on ebay cheap and went for them. Thanks for the nudge.

I really like the old RCA 5U4 in the Torii now, so they have a lot to overcome. I've never preferred anything but the 5Y3 type in the CSP2 or CSP2+ or ZP3--the larger rectifiers just alter the sound from "neutral" too much for my taste and material.

I have never tried the 5R4 type in the Torii either, but forum member Will has kindly lent me a pair, that I will soon audition. Looking forward to seeing what they do.

I'm with Lon on using 5Y3 types in the ZP3.  It's what Steve voiced the ZP3 with.  I've tried several 5U4 variants in the ZP3, and thought they distorted the sound.  It sounded off.

I like pre WWII RCA 5Y3's in my ZP3, but have found a 40's KenRad 5Y3GT (hanging filaments) that has adds a bit of slam/kick to the sound.

Mike

Got these in. Tried them a few hours. Took them out.

Not for me. Too dry and tight and big sounding, not accurate in my system. Reminded me of the Valve Art 274B. When I can let them burn in for a day or so I will and try listening again.

My findings for the RCA in the Mk III are similar to yours. They may never go back in. . . .

I'll stick to the wonderful old RCA 5U4G that are in now.

Just wanted to share more details about my Torii MK4.

It currently sounds better without the CSP3 in my audio chain.
https://www.decware.com/cgi-bin/yabb22/YaBB.pl?num=1386397153/0#0

At 150hrs, it has really bloomed like a sonic rose.
This will really be the last amp I will ever need.

You have been running your amp 15 hours a day?

I was going to start a new thread but decided to ask my question here.  A few days ago i took out the KT66's and put in some  Siemens/RTF EL34's.  I was surprised at the difference...I prefer the EL34's...at least for now.  My question is, has anyone tried the 6L6 type tube in a Torii.  I'd also be interested in what input/signal tubes people are using in the Torii and CSP3 and their impressions.  I'm using some Amprex 7803's in the Torii which I like.  Mark.

I must agree tube rolling is expensive, I have settled on RCA 5U4GB rectifier Top O Getters, Sylvania OA3, matched quad RCA 6L6GC Black Plate, Mullard gold pin E88CC 6922. I was originally a bit disappointed, but now a few months later the sound is really coming along nicely, especially using my Klipsch RF7ii, at first they were way to treble sounding, I have put a 10 ohm resister between the cross overs to get a bit more bass. I purchsed the speakers same time I got the amp, so both bits of gear sound a lot warmer now, I only play records on this system. It is pretty hard when the speakers have 101db senstivity, I have to buy new or mint condition records, anything less is a waste of time.

Thanks for the update will. Glad you are enjoying the amp so much!

LS,

I imagine you will be impressed with the EL34s, especially since you are a tube guy and can mix and match to refine. What I think I heard was all that is reflected in the MKIV refinements over the MKIII, as well as the long heritage of the MKIV development having been part of an EL34 lineage, the EL34 MKIII being its starting point. I don't recall how it went exactly, but suspect Steve did development of the IV with EL34s, and later, in refining the design and voicing, got to preferring
the KT66 for their many good qualities.

It of course depends on the other tubes, and the stock Ruby 5U4G, OC2, OC3s, and EH 6922s are all sort of big and/or open.

All in all, I suspect there will be a number of folks who prefer EL34s and a number who prefer the 6L6GC/KT66 family, and probably ones like me that like both.

Will

It has been a couple of months since I listened to my Torii MK4.

I have lost track of the exact number of hours in total but I believe that my amp and current tube/speaker combination has reached a new final level of musical enjoyment.

The forgiving nature of the Torii MK4 now applies to every piece of music which I play on the system. I suppose this was the trait of the Torii MK3?
By "forgiving", I'm referring to the aspect whereby one can listen to every single track of any CD and not be put off by any song.
Most amps and audio systems are such that one can only listen to a couple of "favourites" and have to skip the other tracks.
This situation no longer applies to my Torii MK4.

In addition, I'm finally at the ZEN stage whereby I no longer analyze any of the music tracks.
Every music track I play just grabs me and makes me float in the music.

I also mentioned earlier that I was using mismatched 4 ohms speakers on the 8 ohms taps.
Now I really won't consider getting the 16ohm ZUs as originally planned coz I really don't need it any more.

I sincerely hope all other Torii MK4 owners out there will also reach this audio level with their audio chains too!

Just a quick summary of my audio chain:
(No more need to tinker anymore!!!!
Oppo 95 -> SoundSilver symmetry silver cables -> Torii MK4 -> Clearday DoubleShotgun silver speaker cables-> Alesis Monitor One MK2 Passive speakers

Tubes: ALL NOS
(Also finally no more tuberolling required!!! Whew and a tremendous sigh of relief)

Brimar 5r4GY rectifier "D" getters
RCA NOS OA3 "D" getters
RCA OC2 "O" getters
Holland Heerlen made Pinched Waist PCC88 "D" getters
GEC Gray glass KT66 ("CUP" getters??? my guess since the gray glass obscures my view)

Hi Will,

Thanks.

My current Torri MK4 combo now allows me to enjoy redbook CDs, and even MP3s too!
I have some music tracks bought a long time ago from Amazon and they were only available in that format.
The MP3s no longer sound like CRAP.

Hi res files still sound better but I am no longer restricted to just hi res music as when the Torii MK4 first arrived in my home.

My Tony Bennett Duets redbook CD currently sounds like a "live" jazz performance is taking place in my home.
I won't even need to get a hi res version if such a thing exists.

I couldn't be more pleased with the results you're all getting with the MK IV post burn-in and just wanted to drop in to say hi and give you some insights...

My favorite input tube in the TORII MKIV is a Siemens PCC88 / 7DJ8 long bottle.  However, 7DJ8's in general are great due to their high linearity in this amp.  Really tightens the bass on problematic speakers not to mention the transparency and silkiness are amazing.  

My second favorite is the 6N23P and I am trying to ship TORII's with this tube in place of the Electro Harmonix 6922 due to recent noise issues with the current batch of EH6922's.  

The 6N23P tubes are all over the place matching wise.  I bring this up because I found in the TORII MK IV as well as the Mystery Amp, it is important to have both input tubes matched in gain so that both channels put out the same amount of power at any given point on the volume dial.  With dual volume it of course wouldn't matter, but with a single ganged volume control it's nice to at least start with perfectly matching channels.

So using the 6N23P I installed 10 tubes in the MK IV, one at a time and measured the power output from the amplifier to see how big the differences would be.  (iPod as a source with 1/2 volt output) and the amplifier turned exactly half way up, which represents a nice healthy listening level on most any speaker.

The lowest tubes allowed the amp to put out 2 watts RMS, while the highest tubes allowed the amp to put out 13 watt RMS at the same volume setting.  Also the weaker tubes that gave the 2 watt figure limited the max power of the amp to 20 watts, while the stronger tubes held perfectly clean past 30 watts.  

Bottom line is that you don't really want to have 3.4 watts on one side and 6.5 watts on the other because your imaging will suffer as well as dynamics.

And as far as I can tell when studying the amplifier at listening levels there is a PEAK RMS level of 2 watts with the average being less than 1 watt.  However, the peak power at this same listening level is over 17 watts making it's headroom exceed 12db on the weakest input tubes.  Of course if the music wasn't compressed and we had normal strength tubes this same level would yield almost twice that.  Ahh, the magic of tubes... 24dB of headroom is more than most CD's with compression of any kind so the dynamic headroom of the amplifier exceeds the ability of the recordings.

Anyway, if you run your TORII MK IV's with EL34's and haven't tried 7DJ8's be sure to do so.  Same is true for most other output tube choices as well.

I have been listening to Siemens tall bottle PCC88/7DJ8s for a few days now. Not enough for them to be burnt in, but they are really sounding good here too with cryo'd Tungsol KT66s....rich, balanced, warmish, and detailed.

Hi everyone,

I'm a big fan of the Game of Thrones ( "GOT" ) mini-series ( music + show ) .

Wanted to share some more of the great experience I am having using the Torii MK4 in a home-theatre setup.

I am getting amazing 3D holographic sonics with just a simple 2 speaker system without any subs or room treatment .... Blah blah blah.

For e.g., during the opening sequence of the GOT, there is an orb representing the Sun. There is a sonic effect of "sizzling" heat emanating from the Sun from different vantage points from a 3D sonic viewpoint.

The sound of the sizzling heat was so intense and realistic that a family member sitting on the sofa with me jumped slightly coz she thought that she would be burnt to a crisp by the Sizzling Sun!
There is no real heat generated, of course, except from the tubes but this just shows how realistic the Mk4 can render 3D surround sound for home theatre usage!

Hi LR,

I've seen the online pictures of your wonderful setup.
Your listening space is more demanding than mine.

My music / home theatre room is a cozy man-cave whereby my position is slightly further than near field listening - about 12-13 feet away from the speakers.
This is why, IMHO, I could  still get those 3D effects without having to fiddle with room treatments and such , which I believe is required for most listening rooms.

My setup is based on just the simple principle of the audio equilateral triangle.
I also went through a diverse bunch of interconnects etc like most people until I reached audio nirvana.
System synergy was also by luck, I suppose.

6V6 will not work in this amp.

I have not tried 6L6 in the amp. The 6L6 is an older development that the KT66 was meant to improve on. According to Steve's tube comparison chart, a 6L6 offers an overall wetter tone (more lush?), less power, looser bass and muffled highs. Why anyone would want that over the KT66 or EL34 is beyond me.

Just ordered a quad of TAD 6L6 from cryoset. Using the KT66 has made me want to experiment. With the bass control on the Mk III I can fix any loose bass. My recent very positive experience with cryo'd TAD EL84 in my Zen C amp has me wanting to try more TAD tubes.

I have about six hours on a matched quad of cryo'd TAD 6L6WGC-STR in my newest Mk III and I am enjoying the sound. Sort of a cross between the cry'od 6CA7 and the cryo'd Tungsol KT-66 that I have been using recently. Quite dynmic and rich sounding, not quite as big and open as the KT-66 but more so than the 6CA7 and a darker, richer sound. Very promising, let's see how they burn in. I've been quite impressed with TAD tubes, they are very well made and the EL84s I bought for the C amp in my Dad's system sound superb.

I'll keep you posted. So far, 12 hours or so in, they're doing quite well. Like the 6CA7 they impart a vintage like sound. They have plenty of power for my needs. No real sonic detributes.

Thanks Will.  I'll keep them in mind for down the road. A lot of great choices.  Of course I still really like the OEM Tung-Sols, wonder it the cryo'd version do anything better.

But, it's all kind of moot for now.  Every time I start to think about ordering more tubes, I see a record I buy instead.

Greg

P.S.  Hope you are still enjoying the Mullards I sent you.  You're probably right in that I didn't give enough time to burn in.

Well, ultimately the cryo'd Tung-Sol KT-66 are a better fit for my Mk III than the cryo'd TAD 6L6WGC-STR. I just can't not have that wide open midrange that the Tung-Sols bring, along with the forgiving top end. The TADs are quite good, but just not quite "involving" enough at this time in that machine. I'll put them back in at some point when more broken in.

In the meantime I've put the cryo'd TAD 6L6WGC-STR in the Torii Mk II that I have in my Dad's system ast the moment. They are sounding very good there. The Mk II has a slight retro vibe to the sound in comparison to my Mk IIIs and these tubes and the ERRs both complement this well. In the opposite of what Jim quotes Steve as saying about 6L6 tubes, these have a ver upward tilt with a tight and focused bass. At least in their current status of a few hundred hours on them. I've had to dial the treble way back with the treble cut circuit, but doing so I have a very nicely balanced and dynamic presentation, well-suited for the classical music that gets spun in this system. And they are very robustly built, quite handsome tubes.

Anyone try TAD KT66 from Cryoset in their MK4 ?

Thanks
ckc

Wow. You don't listen very loud!

[EPILOGUE - NOS PHILIPS METAL BASE EL34 vs NOS GEC KT66 GRAYGLASS]

In my audio chain, I am now 100% convinced that the NOS Metal base Philips Holland EL34 beats the crap out of the NOS GEC KT66 Grayglass tubes.

Why?

After my initial experience with the EL34s described in the above post, I started to seriously think about changing the settings on my MK4.

Voila!

Previously, I (erroneously) thought that with the EL34s, there was a big sacrifice to be made to the low end Bass and high end Treble.

So what I did was to

(a) Turn "on" the Bass Switch
What's interesting here is that with the KT66, the bass is nice and tight and impactful when the switch is turned "off".
When the switch is turned "on", the bass becomes over boomy.

The exact opposite happens with the EL34s. Weird but true!!!
I simply turned "on" the Bass switch this time.
The bass is now nice and tight with the EL34s and there is no longer such a pronounced difference between the two.

(b) Treble Switch
With the EL34s in place, I also maxed out (clockwise) the Treble switch.
The sound of stringed instruments also improved by a noticeable margin.

With the Hazen Grid Mod activated, sonic clarity improved by quite a fair bit.

The soundstage depth also improved and the main vocalist became more "3D" like and centered in the Phantom center channel.

The EL34s add a special vocal "presence" to the midrange of the music.
Vocals seem to be slightly forward now, which is what I favour coz' I also use this setup for movies.

With the EL34s in place, I simply fell in love with my Torii MK4 all over again.

The other members of my family also asked me what I did to my system to improve it by such a wide margin.
This is my personal litmus test for tube-rolling because they are independent casual listeners.
In simple layman's terms, it just "sounds better".


Cheers!


My Audio Chain consists of

Oppo BDP 95
-> Soundsilver Symmetry Interconnects
-> Torii MK 4 ( default fuse)
-> Clearday Double Shotgun Speaker Cables
-> Alesis Monitor One Mk2 (Passive) Speakers (TEC 1994 Winner)

Tubes Used (Kept Constant during output tube-rolling)

Rectifier : Brimar 5R4GY "D' Getter
VR Tubes : RCA 0A3 "D" Getter,
                RCA 0C2 "0" Getter (any "D" getter versions out there???)
Preamp tubes: Holland Herleen Pinched Waist PCC88 "D" Getter

Output Tubes ( Changed in Shootout)
Output Tubes : NOS GEC KT66 Gray Glass "D" Getter
                      Vs
                      NOS Philips Holland Metal Base EL34

MK4 Settings
Speaker Impedance: 8 Ohms
Reconstructive Feedback : Off
Bass : On
Treble : MAX "ON" Clockwise Position

Hi Lon,

In my system, I can't believe what I've been missing out for almost a year with the KT66 in place.

I think I've finally cured my case of "audio upgradis" syndrome for at least the next decade.....

Cheers!

Hi Lon,

If I had the MK3 like you, I'll also stick with it.
With the right tubes in place, there is no reason for any further upgrades.
Unless Steve comes up with his new OTL power amp....

Kudos to Steve for having the vision to include a tweakability factor to his line of Zen Torii amps.
Offhand, I can't think of any other tube amp maker with such an option.

In a positive way, these adjustment knobs help to mitigate the financial risk of trying out new expensive audio components.
For example, someone who introduces a new bass heavy audio cable can still make a bass adjustment via the Zen Torii amp.

Hey will, just a clarification: I may not have mentioned it often here but a few months ago, at Mark58's urging and pointing out, I tried some Amperex 7308s in my main Mk III and they are the first of the 6922/6DJ8/7DJ8/6NH23 etc. type of tubes I've really liked of any make and model and I have built the sound around those rather then the 6N1P tubes now. The extra gain was a plus for use with my DVR (especially when running my DAC straight in and when the DirectStream arrived, which has a lower gain output.)

With the DirectStrean burned in for the most part, I now have put the CSP2+ with Jupiter caps in between it and the Torii and I'm still using choice (I went through a lot of different ones!) 6N1Ps in that and have the added gain I was craving a bit in there with little or no loss of transparency. I'm going to experiment with 7308s in the CSP2+ as well, have some on the way. Sound is really really really good right now and I'm beginning to sink back into the sound and not be analytical once again, whew. Soon I'll put the Tung-Sol KT-66 back in and see how they stack up against the now seasoned Genalex; I've had so much burning in for too long, I want to just enjoy an untampered with system for a spell. Especially as caregiving has become even more complex and stressy of late.

I've read lots of good things about those fuses. I may try them out one day. I'm pretty happy with the FUrutechs I have in place though.

Yes, the 7308 seem a lot different than the other types in that series and I've enjoyed their rich strength. No 6922, 6DJ8 or 7DJ8 have impressed me like this. (As you know the other tube complements have a lot of influence). Looking forward to seeing how they work in the CSP2+. . . .

Oh and also what has made putting the CSP2+ back into the chain possible is I found a used pair of the VooDoo Cable Ultralinear ICs so that I have those in the link both to and from the CSP2+. Ah. . .that's the ticket.

I have a pair of Amperex recommended by Mark in the Mk III and I have a Seimens and two unbranded ones on the way for the CSP2+. (Trying to go a budget route for now; will try using the 6N1P as the CSP2+ "power" tubes first).

Hi everyone, I want to share my experience with some recent VR tube rolling I have done.

If you find that your Torii MK4 is still too "bright" or overly analytical, the following VR tubes will help to add more tube warmth.
This is not at the expense of sonic transparency.

I suggest replacing the default RCA VR tubes with European ones.

I replaced my RCA 0A3 with the British made "CV3798"
http://www.r-type.org/exhib/aaa0723.htm

I also replaced my RCA 0C2 with the British made "75C1" tube
http://www.r-type.org/exhib/aas0044.htm
http://www.radiomuseum.org/tubes/tube_75c1~2.html


My Audio Chain now consists of :-

Oppo BDP 95
-> Soundsilver Symmetry Interconnects
-> Torii MK 4 ( default fuse)
-> Clearday Double Shotgun Speaker Cables
->  Zu Audio Soul Superfly Mk 1 b speakers

Tubes Used

Rectifier : Brimar 5R4GY "D' Getter
VR Tubes : STC CV3798 / 0A3 "D" Getter,
                Mullard 75C1 / 0C2 "D" Getter
Preamp tubes: Holland Herleen Pinched Waist PCC88 "D" Getter
Output Tubes : NOS Philips Holland Metal Base EL34

MK4 Settings
Speaker Impedance: 16 Ohms
Reconstructive Feedback : Off
Bass : On
Treble : MAX "ON" Clockwise Position

Hi Lord Soth,

Give me some feed back on the performance of the Clear Day Double Shotgun cables with your speakers and amp. I have the Definitions MK 111 and have ordered the shotgun cables to be used with same amplifier.

George

Hi Greg,

M VR tubes were really virgin NOS covered with dust.
The VR tubes need around 20 hrs of breakin before they open up.
I went from "did I make a mistake??" to "OMG" after the breakin.

Hope to hear from you again when you have received them.

Cheers!

Dang, just got an email from brent jessee recording stating the CV3798's are out of stock . LS, would you mind posting a link for where you got yours?

Thanks, Greg

Great, thanks.

Hi Will,

So I had been going back and forth with the kt66's and the el34's with the ob3 vr's.  Liked the mids with the 34's,  bass and treble with the 66's.   In the last month I was using the 66's and saw LS's report on the British oa3's and oc2's, specifically the warmth they brought and I realized that that was what I was missing.  So I replaced the ob3's with the stock oa3's and I'll be damned, there was the warmth I wanted.  And, the best part, the kt66's and oa3's play well together, like best friends.  : . No bass density issues here.   Really well rounded sound, rich, liquid and detailed.  The bass is powerful and yet controlled and nuanced.   I'm real pleased with the sound I'm getting now.

That sounds great Greg. Yes, the KT66s I have have nice controlled bass. Interesting the OA3s are good there with them. Are yours the Russian straight bottle? Those seem the cleanest and most open sounding of all I have, so they push the power tubes harder but with less density.

Nice.

Hi Greg,

Glad to hear that you managed to locate some of those rare British VR tubes.

I only managed to get mine from sporadic raids via EBAY.

It still never ceases to amaze me when a couple of small glass bulbs can make such a big difference in improving the tone of a tube amp.

Cheers!
😃

have we decided on a good KT 66 to go in this bad boy with the stock tubes?

I have received my Torii a couple of weeks ago with the tubes that Steve advises and boy does this machine sound good.

Out of curiosity, I'd like some advise on possible changes to the tubes to suit my musical preferences: I listen to dub from the 70's, roots reggae and late 70's early 80's funk and sometimes Rolling Stones, Dylan, Springsteen.

thanks

not sure this is the right place to post this, but I stumbled upon this awesome shootout report of 13 tubes

http://www.head-fi.org/t/761078/6922-tube-review-17-top-6922-6n23p-e88cc-cca-730...

Here's my brief experience with the KT66 v. EL34 dilemma people sometimes wonder about.  I think a lot of it depends on your speakers.  I have Klipsch Heresy's, which are a sealed design.  They have great tight bass all by themselves.  When I pair them with the KT66, it choked the life out of the music I listened to.  The music through the Klipsch Heresy's sounded anemic and I really felt that I had to supplement with a subwoofer.  

I recently switched to the new Mullard EL34 that Upscale sells.  This was a revelation after listening to the KT66 for 5 months.  The EL34 bass is loose and boomy, but with my Heresy's are just right.  I keep the bass control switch off and my Heresy's sound great, WITHOUT A SUB.  

YMMV, but too much bass control can be a bad thing.  Plus, now I get all of the benefits of the Hazen Grid Mod, which has been really fun to listen to as well.

I really wish I would have done this sooner.

Hey Paul, great to hear! Isn't it amazing what a rectifier will do in these machines?  I recently popped a 'forties Philco 5Y3G into my CSP2+ and was really pleased with the change. A bit more dynamics, a bit more clarity. The older the better seems to be the rule I am finding with rectifiers! 'Forties RCA 5U4Gs that I used in my Torii Mk III for years were fantastic! Now I have 'Forties 5V4G in there. . . just works best with my tube complement.

Sounds fun Mac! Good thinking on waiting out the burnin while exploring the tubes you already have or are getting. Your amp will continue to develop for hundreds of hours in meaningful ways. Having a nice variety of tubes to ride through it will be really interesting along with the Torii settings. But also waiting for expensive rare tubes is well thought out I think. I really enjoyed the Tung Sol 6L6G coke bottle shape for a long time.

Nice!

Mac, could you name the input tubes recommended by Steve with numbers and year of production.  I have often thought about trying the RCA 6L6GC's and could have gotten them at a good price but only in pairs.  Also I really like my RFT EL-34s too much.  I've tried the Tung Sol KT-66 that came with the Torii MK IV and  some Russian power tubes.  I've focused mainly on tube rolling in the ZP3 and the CSP3 and input tubes in my Monoblocks.  The Torii has had White Label Amperex 7308's almost from the beginning in the input positions...no rolling there. Mark.

Hey there. I've gone through 2 quads of the Gold Lion KT66s and 1 set of the KT77 GL only getting about 700-800 hours on each quad before they sound tired.  Is this normal?  Does anyone have other suggestions on something that might last longer and not be NOS expensive??  Just curious.  THANKS!  PS....can you use KT150s in the Torii MK4??

Regards,
Paul

Looking for suggestions on a solid functional set of matched quads. Budget stuff please, no pricey NOS collector tubes with perfect original boxes. I see matched quads on ebay for as low as $50 for all 4. Are these  all junk? Any of them solid and reliable? JJ? Valve Art?
Sonically, I am pretty fixated on midrange at the expense of all else.

I like these in my ZMA.  They can be found a little cheaper on ebay but not necessarily in matched quads.  I think others use them in Torii III and IVs.

http://www.cryoset.com/catalog/product_info.php?products_id=335&osCsid=d9c6f1f7d...

I should've clarified, I'm looking for EL34s. (It's a Blue Torii)..
Any preferences for EL34 matched quads?

Will, Lord Sloth, Lon, Et al,

i just bought a bunch of tubes recommended here.  the 6l6's, some kt77s, and a few el 34s.  I also bought some new rectifiers.  Now i'm looking into input tubes but i've kind of busted the wallet for now.  Anyone got any lying around they want to send to a brother??

Hey guys.  Thanks for the suggestions on the 6P3S-E from Cryoset. For the last couple years I've been using GL-KT77s but they seem to wear out fast (7-800 hours) and start sound dull but I really like their sound.  After about 20-25 with the 6P3S I have to say I am pleasantly surprised, especially for the price compared to the KT77s. The mids sound great....although I think you lose a little on the top end but the bass is better than the KT77s....maybe a little more...but not flabby. Thanks again for the tip.

-Paul

Anyone have any experience with the valve art KT 66 tubes? What about these: Tungsol Reissue KT66 Power Vacuum Tube, Matched Quad https://www.amazon.com/dp/B004XJCMEG/ref=cm_sw_r_cp_api_p2h2yb9EGX1VG

Thanks!

Enjoy yourself! I hope you roll and find a great complement.  I'm NOT rolling tubes. . . I love what I have in my Torii Mk III so much right now, it's dishing out everything just right!

Amperex 7308
RCA OA3
"British made" 75C1 (OC2 equivalent that Will hipped me to)
TAD KT66

Just perfect for the "all around sound" I want for my collection with my sources and cabling and speakers. I'm so happy!

Hey Will, after thinking the Amperex white label 7308 was my input tube of choice, I have changed my mind after purchasing three pairs of NOS 1962 USA Amperex White Label PQ 6922s.  I think it's that they are a little less detailed or have a less prominent high end...a little more mellow?  Also the Bass seems a bit more dynamic and punchy than the 7308s. They are now in both the Torii MK IV and the Zen Mono Blocks.

Also have you seen my question in the ZP3 thread...i think you may know the answer.  https://www.decware.com/cgi-bin/yabb22/YaBB.pl?num=1402147415/79#79

Thanks, Mark.

Hey Mark, I liked the early 60's white American PQs too last I checked. Different batches and all, but I think I recall them being quite similar, maybe a little cleaner, maybe and a bit less textural than normal American Amperex 7308s and 6922s, balanced a little toward bass, the combination changing the whole feel some...I felt like the detail was all there, but a little different balance and a little less "forceful" overall...subtler and refined. I am not home so can't double check. Does this sound right to you?

I liked both for different reasons, but as has been my pattern, I rarely use 6922 types in the Torii... They tend to be just a little too clean and powerful there for me. I use them most of the time in the CSP3 though, especially in the power section.

For a few years now, I seem to be caught by what appear to be early Siemens ECC88s (the ones I use most, late 50's/early 60's and labelled CBS and IEC/Mullard)...lower key than 6922/7308/E88CC/E188CC types, but nice extension and balance, neutral, mellow...with pretty rich fine detail character. This tube is variable also though. I have one pair labelled Siemens, and depending on the company it is with, it can get too bright/clean for me...more 6922-like in ways, with big bass and great power and articulation, and all this along with the ECC88 tendency toward inner spaciousness. Maybe Siemens kept "the best" for themselves, and I prefer the more complex character of the "2nd string"?

I will check the link you posted later if we have internet access next campsite.

EDIT: Mark, I checked your question about the 12AX7s, and sorry to say I have no real experience with that tube type.

I'm not sure if I have the same style rectifiers but I'm enjoying their sound. The 75C1 are definitely a nice change and helping my tube complements. I also installed a new jumper of silver wire between upper and lower sets speaker connections (one leg) on the HR-1s which are helping create a very nice sound, and then today I finally got the 36/10 Duelund resistors to run on the other side and replaced the Mundorf Supremes with them. The resulting sound is wonderful if just a tad bass-shy--previous experience with the other pair of Duelunds leads me to believe that will come in time.

The system now sounds like the best solid state I've ever heard WITH that fullness of note character that the best tubes bring. I'm hoping I can just leave things alone again. (How many times do I say that?) The Torii/HR-1 combo just keeps on revealing more and more ways to excellent sound. I hope they do for a few more decades!

Interesting. I always really like the change-up from different rectifiers in the MKIV, but they tend not to last long. Back to GZ32 or 5V4Gs I go, being pretty ideal these days in my system/room. Even the 5V4Gs so far rarely last real long.

I think part of why the Sylvania 5U4G-ST are still in the MKIII is that I use it mainly for background music for healing work, and with Hytron OC3 and Tesla PCC88, it is beautifully open, textured, spacious, and articulate at low levels. I need to try some 5V4G or GZ32 there.

Yes, I agree! I usually end up back in the same neighborhood these days after experimental forays! Fun to have "standards" that work, and fun to explore variations...

I can see why the RCA 5V4G-ST has been good for you. I can't use it in my setting, but can hear how it could be just right in the right setting. Since you tend to end up back with it after playing other great choices, it is clearly doing the right things there! Balance is balance!

i'm starting to think it's the input tubes.  i'm currently using the tubes my amp shipped with. what are some other suggestion you guys might have??  what i'm noticing is that currently i can hear the noise floor.  is it possible to make that "white noise" go away?

i'm going to have to do some cable rerouting first and foremost.  i like my sound as it stands but still wish i could get the bass a bit tighter.  using the stock inputs and OA3s.  rectifiers are the sovteks and the power tubes are the kt77s.  i tried my old gold lion kt 66s and the noise floor was still there and the bass was even flabbier than with the kt 77s.  the noise is on both inputs and it's constant.  not crackling like a tube going or a connection failing.  it's basically white noise.  my guess is its all the cables i've got in a pile or the input tubes.  what would you suggest for input tubes if you want tight bass and clean sound?  i'm looking to "clinical" up my amp sound as i've got a tube preamp as well.  thanks!

I agree with Lon's OB3 suggestion. In my experience with Toriis, flabby bass can be in part too much of it for your space. As I understand and hear it, OB3s will notch the power of the power tubes back a little, opening the sound and reducing bass intensity...really it will calm all the intensity...relaxing the overall density and push a little, giving more space across the spectrum. A good first step. I have never totally liked OA3s here, preferring OB3s.

Interesting the white noise, not hum...For inputs, if you don't hear any other problems, and like the sound, it may be good to see how far OB3s take you toward your ultimate sound before deciding on an input. Then, if you would like to take the opening and tightening further, a 7DJ8/PCC88 type would likely tighten bass some, and increase space, sense of articulation, and textures. They are all different though, as are all the 6922 types, and why I would not be inclined to recommend a specific one until you heard the OB3 change.

Another shift that would move this way in different sonic way is a nice GZ32 to replace the GZ34 Sovteks. Sovteks are pretty nice reproductions, but not in the same league as the much more expensive Mullard types they copy. Most Mullard/Phillips made GZ32s are in the same musical quality arena. Similar to OB3s, the slightly less powerful rectifier would open the sound of the whole...calming density enough to open the sound and tighten bass, and similar to the right 7DJ8, more texture as well.

Both the OB3 and GZ32 could also be taken a step further with OC3, and GZ30s.

I have bought several pairs from ebay.

I just used this search phrase: "OB3 pair 0B3" and several pairs of Sylvania appeared available at cheap prices.