I want to bring your attention to this Kamran posted in another thread.



A few years ago I was curious about this and eventually placed the idea into long term storage.

He kindly repaid the favor and started watering the seed I stored away.

There was another thread started about the STR… it quickly turned into a dumpster fire, so starting fresh. I didn’t relook at the entire thread, I don’t think anyone actual owned one to tried one so it was all speculation anyway.

Well I’m not speculating anymore! I have a STR-1002 Super.




These tube really are JUMBO!


When I first held a EML 5u4g I was giggling how big it was... now it looks like a small guy.



There is almost no information about these so I’ll explain how it works to the best of my understanding.

The STR requires a power cord. This power, powers the heaters of the tubes.

There is an umbilical cable that fits into the rectifier socket on the component you want to use the STR with. The component “sends” AC down the umbilical cable to the STR for rectification. Then the STR sends DC back to the component.

The STR has a few different modes of operation. It can use 1 or 2, 4-pin jumbo tubes as diodes. So running two tubes you get full wave rectification and 1 tube half wave rectification.  It also includes a SS rectifier so you can run 100% no tube rectification. You can blend the SS and tube rectification. It’s also possible to run different tubes and “blend the sound like blending two different juices”

I’ll speculate a bit here. By offloading the high current heater from the rectifier the component power supply isn’t working as hard. It also reduces electromagnetic fields inside the component. By separating and spacing apart the two diode-tubes there is less interference between them resulting in a cleaner signal. Look at a standard rectifier everything is jammed in there really close.

The 4 pin jumbo tubes are amazing. Al from Space Tech said that when using DHT as a rectifier people cannot wrap their heads around how much they copy the same sound when used as a power tube. I’ve only listened to 4 pin jumbo tubes in show settings so I don’t know what their sound is. Based on others reports of how the jumbo tube amps sound, when used as a rectifier they do impart their sound signature.

What is that sound signature?  It’s the most involving reach out and touch the music sound I’ve ever heard. Music flows through out the room in a magical way.

The thing that is really hard to wrap my head around is how it really adds everything.

In the Lampi TRP I was running a Sophia 274b Aqua II and then the EML 274b Mesh. The Sophia is bold and juicy with plenty of density. The EML is more extended and faster, much better attack and space.

Running 1x PSVANE 805A Classic—half wave rectification—It’s better than both at the same time. I’ll say it again, it takes the best of both tubes increases the goodness and blends them together.

The first thing that I noticed was how everything was more vivid. My old definition and understanding of density has entered a new paradigm.

I’m hesitant to start talking about how much more detail there is. Often for me when someone starts raving about detail bright, harsh and fatiguing come to mind. None of that exists.

Details like cymbals being lightly activated when the kick drum is struck. Not since I added all the room treatment have I been so blown away with now much things have changed.

Another thing that caught me by surprise. Having the STR-1002 plugged into the TRP the entire system sounds like it has unlimited power. Which is something that I would think would be in the domain of the amplifier.

I received a pair of Linlai 845s, I bought the internally coated ones specifically because the 4 pin jumbo tubes are as bright as light bulbs. At night they offer a nice amount of illumination without being too bright.

The first few hours I was not impressed with them preferring the single PSVane 805a Classic. The 805As had been burned in for a day or two at STL before shipping and the Linlai 845s are fresh. After 5 hours the 845s started to sound better. As of right now I have 10 hours on the 845s. I’ll comment on the sound difference once I have more time on the 845s.

I did elect to have the choke option. The choke smooths everything out, reducing dynamic impact and some speed. It offers a more euphoric dreamy sound. I only have a few hours with the choke engaged, I want to get some more hours on it before I really did into the differences with and without the choke.

I can see the choke being a nice option for the nights I’m tired and want to float off to sleep.

I'm still trying to wrap my head around how much of an impact this has. It's really giving me everything I've wanted. All the mythical things that seem out out reach this is providing. I do want to offer a bit of a context. I have a dedicated room with literally 3+ tons of treatment.

Sometime in the near future I'm going to bring it over to my brothers place and try it on his UFO25th. This should be a more "real world" experience.

I'm talking to Al about making a custom 4 tube version for my amp.

Me and my big mouth lol!  All kidding aside, I’m super glad that this nudge amounted to a profound positive impact to your already impressive rig.  Based on my observation, such changes are hard to achieve, when you already have a very resolving setup (and room). This speaks volumes of how compelling the Super Rectifier is and has already shot up high on my  radar.

Love the custom chassis—-so much better than STL’s typical industrial design.

Questions:

Can you elaborate on Full vs. Half Wave rectification.  Why choose one over the other (granted you have the option to do in the first place).  

Why did you opt for the jumbo tubes vs. running DHT’s?

And here I was thinking I had run out of components on my wish list! This is interesting.

Possibly this:

https://techpp.com/2024/04/02/grok-chatbot-vs-chatgpt/

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Obviously I'll talk to AL about this, but what the rectifier does is provide the (rectified) high voltage B+ signal for the tube plates. A single rectifier does this for 2 channels of a stereo amp, I don't see why it is impossible for a single STR to provide 4 channels for two monobloc amps as long as long as the current requirement is manageable. And it ought to be for 2 UFOs. Whether it could swing it for higher powered amps is another question. If/when I have this discussion with AL I'll certainly report back.

Hey Groovysauce,

I have seen these before as I was looking at the Schumann products.

Interestingly  space tech also produce amps and pre amps and the reviews I watched suggested the super resonator didn’t do as much for these products which suggest they must be stunning. Have you had a chance to hear their  pre’s or power amplifiers Nigel?

I have not listened to any of STLs amplifiers.

Bloodlemons, That's exciting!

What is drawing you towards the mercury vapor tubes?

ZP3 vs. CSP3 I'm super excited to hear which you find has the greater impact! It is really hard to say. I'm guessing adding to the ZP3 might be more impactful. As it will change the source and the CSP3 will work with what it's given.

I just ordered a pair of adapters so I can run 300b and with another adapter which I ordered from ebay I can run 5v octal rectifiers. This will allow me to try it on the amp before ordering another STR.

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Very cool! I'm looking forward to your experience.

I admit I'm easily influenced by you guys, and a STR has been sounding like a better and better idea. I was also thinking about a 104 for my (non-Decware) pre/headphone amp. I already have 300B tubes and various UX4 rectifiers I can use. I'm not crazy about the idea of mercury vapor tubes in the house, but I'm warming up to that as well.

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I totally get that! Sounds like you will have a bunch of options to play with.

I also added a converter so I can use 3B22s in the STR-1002 as well.

I'm also not a fan of the mercury vapor tubes. I'm guessing the chance of it breaking and causing a hazard are very low, rather not risk it.

In some aspects adding the STR-1002 to the Lampi TRP was a larger step up than going from the MAY KTE to the TRP. The upgrade to the TRP was a very significant one too.

Since I've added the STR-1002 my listening sessions have consistently been the best I've ever experienced. It's the most difficulty I've ever had trying to language what I'm hearing. Not only the hearing, the experience and feeling. I'm amazed that the Super Tube Rectifiers are not talked about more.

... they are still cats...

You got that right.  My 21-year-old cat, Chunk, still get into all sorts of mischief.

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Just email AL.

CAJames: I did email Al this morning. I was just hoping to hear some Decware-centric opinions/experiences before I finalize my order.

Groovy Sauce: Thank you for your detailed response. If 805/845 tubes provide the most holographic image, then that's the one I want. Easy decision there!

Nigel,

I have to say that this is by far one of the interesting threads I’ve read in a while.  Sounds like you are getting stratospheric sound with the new Space-Tech rectification.    I’m eager to hear your impressions when you try it at your brother’s house with his UFO25th.  

James…when you talk to Al please report back on whether or not it’s possible to run 2 monoblocks with the Space-Tech.  While I’m in no position right now to make a purchase, it would be great to know of the potential for a future purpose.  But I think the reality is that in my open space layout in an untreated room, the positive results I would achieve would be diminished.

Dominick: I spent a lot of time deciphering the STL site re: the STR. What I came away with most is that many of Al's orders are custom products in some way, subtle or unsubtle. Based on the options and form-factors available in his stock units, as well as what I've seen otherwise on the site, I am confident that he could build a single unit to serve both of your mono blocks, with a separate cable for each amp, albeit almost certainly utilizing separate tubes for each amplifier, but with a common power supply and housing enclosure, etc.

Likely that would require four tubes and two sets of tube switches/controls, if you want full wave or switchable rectification, or two tubes and two sets of switches/controls if you just want half-wave rectification. Although, if you're having that type of unit custom-built, I don't know why anyone wouldn't fork out for the full-wave/switchable rectification.

I am not a wealthy man, but when I have something custom made that I plan on keeping potentially for the rest of my life, I pretty much go all out, within reason -- essentially "future-proofing" the gear as much as possible. I've certainly done that with all of my Decware gear, in that I really don't think I'll ever replace this system with something else.

I'm "only" 49, and I may put together another system or two for other locations (I already have a modest but pretty cool setup in my home office), but I can't really imagine parting with the Decware stuff for any reason. The gear responds so well and so significantly to tube rolling, gain settings, and other tweaks such as the one discussed in this thread that, in my experience, you can really make it all sound however you want.

And here I am rambling again. Anyway, it would be cool to see what Al could come up with to address your mono block situation. He's very responsive and detailed via email, and I'm sure he'd be happy to help you spec out a hypothetical unit to address your needs.

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Those sound like voltage regulators, not rectifiers. But that certainly would be a big change. However, in my experience, the difference changing rectifiers is much bigger than changing VR tubes.

Actually I should clarify that. There are lots of good/interesting sounding rectifiers, that sound good in different ways. With the VR tubes, there is a small window where the sound works best. Outside of that the VR tubes sound very different, but it is more like different kinds of bad. JMO/YMMV and all that.

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I'm pretty sure they do , they don't have voltage regulators.


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Me too. I want to be buried with mine, like a Pharaoh.

For a few years the Super Tube Rectifiers have been on my radar. Not much information about them at all. Kamran gave me a nudge so send some thanks his way too.

Dom, as of right now the sound I’m getting from the system is like nothing I’ve ever experienced before. After getting a majority of the treatment into my room it was a paradigm shift making it difficult to accurately describe how the system sounds. Since then I’ve tweaked fine tuned and got the system to a place I was so thrilled.

Adding the STR was another paradigm shift. When I get over to my brothers place and try the STR on the UFO25th will be a telling experience. Will it be as drastic in a “real world” setup? Blue Node 2 (I think) or TV -> Holo Audio Spring KTE w/ volume control -> UFO25th -> AV123 speakers with upgraded cross overs They have 2x 5.25” drivers and a tweeter. Zenwave cables. It’s a great system and fun to listen to.

Will it be the paradigm shift that happens in the dedicated room? How much of a change will there be? When adding anything to the system I’ve started to look at it from this perspective. If I add X dollars how much do I enjoy the result? Doesn’t matter what the money was spent on. What is the ratio of $$$ to enjoyment with the UFO25th in a normal room? I’m hoping to find out this coming week.

I asked Al about using the STR with a pair of 2 watt mono blocks. I’ll report back. I’m guessing he could put two STR-1002 in one box so you only need one PC.

James, Adding a unit to the preamp might be the way to go.

Bloodlemons, You are correct, Al told me custom jobs is his specialty.

As far as the 3D holographic sound. Activating the choke is a significant change. Active it gets euphoric, dreamy, enveloping and extra trippy. What is traded is attack, dynamics and precision. I’m guessing 90-95% of my listening will be with no choke.

One thing that keeps showing up is how alive everything sounds and feels.

GS,
You are such a bad influence!  Just kidding!  First it was SFDBs and now the STRs!  I have been trading emails with Al and he recommends using the STR on my CSP3 (“experience an immediate opening of soundstage in depth, width and height by 50%-200% right away, the degree of improvement depends on the models you put in”). My CSP3 is paired with either the UFO25th or my Cary Audio 300b Signature monoblocks (so a 2 for one deal sort of).  Beats ordering two STRs or the STR-1003 for the monoblocks.  I ordered the STR-1002 with 805A and selectable choke.  It will take 3-5weeks to build.  Can’t wait!  Order now before the backlog starts!  lol!  GS and Kamran, Thanks!
Bob

This looks to be an expensive alternative to tube rolling rectifiers. Something was mentioned by the OP of keeping space between the dual tubes therefore elimination magnetic interference? What about that umbilical cord running DC alongside AC current? Also, adding extra baggage to a well tuned Decware system?

Really guys…not shooting this product down but have some reservations about it.

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Hey James…well I feel like a complete idiot with my last string of comments.  Yes I was referring to voltage regulators that I recently changes on my Torii.   Bad brain fart ….because I then I said something more idiotic that my monos don’t have rectifiers ….WTF? And this is what happens when I’m in a conversation with my wife while trying to post on the forum.  

And yes…you are right…swapping rectifiers really can have a profound change on the sound.  The box of rectifiers I got from you really was an eye opener once I started rolling them on the mono’s.  Right now I’m running and enjoying the RCA GZ34 rectifiers.   The type 80’s are next on the list.  

I definitely see the appeal and benefit of the Super Tube Rectifier. I've rolled several dozen rectifiers the past years in my components, and have narrowed it down to one that really works well in my three Decware components, and my main amp, the SEWE300B has enough grunt that a rectifier is not taking up too much of its working fuel. . . . I do think a Super Tube Rectifier might be an improvement and I might try one down the line, but right now it's not a priority. (I keep repeating that to myself over and over.)

That's fair. But you won't see me buying one of these any time soon. it's not possible in several ways.

I get the aesthetic aspect. I think the STR unit with the wood base looks really cool. The umbilical cable could use some love. It’s very flexible and blue. I might need to call up Jonny at Snake River Audio and ask him to make me a custom umbilical with his fancy sheathing ugh, why do I think of these things?

It does have a bit of a mad scientist vibe to it which I like.

I get not wanting more boxes. I wish I had less. Before I got the STR and the first few times I turned it on I was a bit nervous. There are a lot of switches and unknowns. Now I don’t even think about it.

I’m in the habit of turning the standby switch on when I turn the unit off. (all switches down) When I fire up the system, first thing I do is turn on the STR, push the start button on the stylus timer, do a super quick sloppy dusting with the floor duster thingy (30-60 seconds) then turn the STR to engage. Then turn the rest of the stylus timers on and switch on the DAC and amp. Whole process takes less than a minute usually.

Also, if you are about to step into a time vortex into alternate reality what is a 60 second start up process in the grand scheme of things? :p

The Super Rectifier has an IEC inlet for a power cable; many of us wouldn't use a flimsy power cable that the manufacturer supplies. . . we would buy an "after market" one such as the Decware ones, or AudioQuest, Cardas, Shunyata Research, etc.

GS,

lol—I was waiting you to think about upgrading the umbilical cord! And I agree, in the grand scheme of things, what I have noted are minor inconveniences indeed—which is why I’m starting with the assumption that I’m going to eventually get it. I’m just fooling myself that I have regained some sort of control over your influence for the time being, lol!

Tony, I was referring to aftermarket power cables. To the extent the STR comes with a detachable cord, I can see myself upgrading that too.

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I thought about it before I even ordered it. Now that I've "vocalized" it I'm doomed. Ha!

I bet AL could build the umbilical with fancy cable if you wanted.

I finally just committed to my order and sent payment to Al for an STR-1002-SUPER. For options, I'm getting the 805A to 800B converters and silver 4-to-8-pin converters, as well as OFC top caps. I was going to get it in a "deep," single-file configuration in a black MDF enclosure, but Al recommended the same in the black solid oak enclosure -- he says it improves sonic performance and durability, so I'm going with  his expertise on that.

The result should look something like this, but in a black wooden box:



I believe a pair of mercury vapor tubes should be delivered today from Tube World Express. Shortly after I placed the order, Brendan from TWE sent me an email to ask if they were intended for a STR; apparently it's a fairly common order for that application. These are the tubes:

"VT-46A=866A RCA NOS 1942-1944 original boxes (62-62/40 x 2 tubes) - 866A RCA NOS original boxes"

Super Exciting BL!

Going with the wooden chassis is a good call in my book. I like the look of mine. with the dark finish.

Did he say how deep it is with the narrower design?

Just had a random thought this morning: It's so nice to add a component that doesn't require another set of interconnects. Just something that popped into my head.

CAJames: It does!! Luckily, the only component I have that issue with at present is my Transcriptor Skeleton table, which is my "backup" table that is really mostly just for show. It's a very pretty machine! However, I did have my local shop hardwire an AudioQuest Wildcat phono cable to the original Vestigal arm, so being able to swap cables on that table at this point isn't really worth pursuing.

Bob, looking good! Yes, Al is very responsive and quick to communicate.

BloodLemons, Have you gotten any updates?

I still haven’t gotten over to my brothers place to try it on the UFO25TH. I have tried it on my amp…

3B22 xenon rectifiers. I don’t know exactly why two are needed. I do know they will supply 1 amp of current… each. So all power requirements are met.

Unfortunately one of the adapters broke in shipping. Also the SR-200 was damaged too. Canada Post or USPS is not treating these packages nicely at all. When a box is being crushed by machinery doesn’t matter how well it’s packed I guess. I don’t know how they could be packed better besides being in a hard case.

I epoxied it back together and tomorrow I’ll try running two 5U4Gs.

With the 3B22s I got to try the STR on my amp. Two 845s only supply a max of 220ma of current the amp needs 320ma.

Wow on the amp it’s fantastic. The silence and space between the notes is expanded. Resolution has gone up yet again. And the noise floor… already was lowest I’ve ever experienced became even lower! Music just flows like nothing else.

STR and DAC better tone, attack, density, space all improved. Also the density is completely different than what I’ve experienced before.

STR and amp. Still has the traits of it on the DAC. As I mentioned above, the space and silence between the notes is incredible. I need more time to get more into the details. First impressions are very positive.

I tried the 2x 3B22s and the Sophia Aqua II 274B. I’ve been running a pair of SE Aqua II 274Bs in the amp for a long time. It’s a big step up running the SE Aqua II + PSVane 805A through the STR. Tomorrow I’ll try running 2x SE Aqua IIs. I want to give the epoxy 20+ hours to harden before using the adapter.

The one bummer is that when running the 3B22s or 1x rectifier the power supply of the component it’s plugged into buzzes/chatters a little bit. Al said to try running 2x rectifiers and see if that fixes it. Tomorrow I’ll give it a try.

The chattering sound is the same as the sound some components make when they are plugged into the Plasmatron 3.

The noise doesn’t go through the speakers and it’s not noticeable at the listening position. Tomorrow I’ll try 2x rectifiers and see how it goes and report back.

Back to the amp and STR. It’s hard to tell if the difference is more profound on the DAC or amp. The amp can only work with what it’s given. Good thing I have a vinyl setup to try. Since I put the STR on the DAC I’ve only played one or two records. TRP + STR was beating vinyl in some areas and I didn’t feel I was missing anything so I stayed with digital. Amp + STR

I have a pair of the Chinese 300B that Decware sells arriving today. I have adapters for the STR so I can run them for the DAC.

I have a few pairs of tubes now.

PSVane Hifi 805A (stock)
PSVane Cossor 845
Linlai 805-TA
Linlai 845-TA
Linlai 845_DG

I received the Cossor 845s yesterday. Less than 10 hours on them and they sound nice cold out of the box.

They all sound different. Online reports say 100-150 hours to fully burnin for the 4-pin jumbo tubes. I haven’t hit 150 hours on any of them yet. The Linlai 845-TA have almost 100 hours, they have been my favorites.

I’m curious to try a pair of 211 tubes, maybe I’ll let someone else try them. Ha!

I’ll report back when I have more to share.

Popped the Chinese 300Bs from Decware in. 300Bs can provide a max of 100ma each. Running at the max shortens the life. The TRP draws 40ma so 200ma should be enough head room  :p

I've only listened a little since putting them in. Sound different than the 845s and 805s for sure. I want to give them more time before relaying what I'm hearing.

One thing that is consistent with all the tubes. The flow sounds and feels right. Grain and noise floor are lowered. More resolution with no hints of artifacts.

I'm going to be trying the SE Aqua IIs on the amp too so will be awhile before I burn in the 300Bs.

I did buy this nice little piece of retro-tech to help me keep track of the mercury vapor warm-up time:


photo upload free

BloodLemons, I’m not sure why it needs two 3B22s in the adapter. It might be something to do with the STR-1002 has 5 and 10 volt heater settings and the 3B22 is a 2.5 volt heater?

Love the time keeper!

I like the combo of 2x 3B22s and one SE Aqua II more than 2x Aqua IIs on the amp.

Going between the STR on the amp and the DAC has me wondering examining which is more important, source or amp? I’ve never been at this consideration before. From afar I’ve observed and never dove in. Now, as I swap the STR between the DAC and amp I’m on unknown ground. When the STR is on the amp it really feels like it’s being held back by the source (DAC). There is a lot of things I really like when the STR is on the amp.

Putting the STR back on the DAC and there is finer rendered information that the amp has to work with. If the amp never gets all the data then it is playing at a disadvantage.

Right now I’m leaning towards the DAC (source) having a larger impact in this application. Doesn’t mean this is universal. I’m guessing once I get a STR on the amp it’s going to be an incredible jump.

Playing records really showcases what the STR does for the amp. And I really like what it does.

For my tastes the 845s are my tube of choice. I only put a few hours in listening to the 300Bs powering the TRP. The 845s offer more of everything.  I’m really hoping that 4x 845s powers the amp optimally.

I have a few items I’m selling, once one of them sells I’m going to place an order for a custom STR for the amp.

James, I get it, if I was a 300B fan I would want to know what fully broken in 300Bs sounded like.

Everything sounded smaller with the 300Bs. It did have a nice sense of space and expansiveness to the sound stage.

At the end of the day the 845 beat them in all aspects though.

James, I read it how you intended. The 300Bs aren't bad, just not as enjoyable as the 845s.

I've looked at the Elrog tubes. They are so much money and I'm not sure if I will like them more than what I'm using now. I actually prefer the less expensive Linlai 845-TA to the Linlai 845-DG. The DG has more crispness, the TA has a more meaty sound. There are also the KR Audio 845s also a lot of money! Not many people talking about the big transmitting tubes so more of a roll of the dice than more discussed tubes.

With theoretical usable life up to 100,000 hours the lifetime cost isn't too bad though.

The Linlai 845-TAs were around $250 a pair so not crazy spendy.

I still haven't tried 211s.

So far my favorite tubes for the DAC are the Linlai 845-TA and PSVane Cossor 845s.

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This is what I was afraid of . Different rectifiers have made a profound difference to the sound of my system, I'm not surprised at all that different tube combos would have a big impact using a STR.

Very cool! Is it coming with 805 tubes? And do you have other tubes in mind to try?

Looks sweet Bob!

GS,
Interesting.  I opted for the wide design thinking about yours.  I would be interested in your idea about the bright tubes.  Al recommended covering them with metal tubes.  
I will wait for the PSVANE 805A pending how I like or dislike the bright 805s.
Bob.  
PS, Inspired by your Lampi, I want ahead and took the plunge on Al’s DAC (DA-DSD 512-2 Super) and see how it will compare to the Holo May KTE. It is arrives this Wednesday.

Nigel as well as the seasoned DECWAREians here have provided so much advise and inspiration to me and have made my listening experience improve so immensely the past couple of years. STR, SFDBs, Cryotone, Holo May and of course DECWARE!
Bob

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Oh Wow! lots of fun heading your way! What is the ETA?

BL, Looking good!

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I ordered a 3.5" x 6" charge pipe that I'm going to put around the tubes. If it works well I'm going to paint or powder coat them. I'm thinking I'm going to put some sort of spacer under them so there is some air flow. Not sure what I'm going to use for that yet.

So glad I came across this thread….I have a  str-104 mk2 in route and I wanted to ask the experts for some advice. I chose the 104, after many emails to Al, because I want to use it on either my Torii jr v2 , Supratek pre or a 300b amp on order.  It was the most flexible and accommodates all components at an affordable cost as well.
Questions:  
- any 5v tube combinations that you really liked to recommend?  Cannot be 2 DHT need at least 1 Rectifier type.  (2-3b22/274b, 2 5u4g, 3b22/866a…)
- anyone know the power mA required on the ToriiJrv2?
- how do you like the choke?  I passed on the choke option since I listen mainly to blues, light rock, folk, pop…Al’s advice.
-do power cords make any difference since it only draws for the heater?
Open to any other tidbits of advice.  Look forward to my new fun toy

Hearafter, I'm not an expert at all, I'm still in the excited learning phase.

Did this thread inspire you to get a STR or did you find it after ordering?

Did you get the adapters from Al so you can use octal rectifiers?

The 3B22s I got from Al sound good.

If I was re-ordering I don't think I would have gotten the choke option. I do run with the choke every once and awhile for a different flavor. The choke offers a more laid back and dreamy presentation.

Another thing to consider is DHT have much more resistance than rectifiers. This means there is a bit of voltage drop when using DHTs. When I tested 2x 845s on my amp which needs 300-320ma. It wouldn't bias the tubes as high. Running the 3B22s and 845 the bias was fine.

I haven't tried swapping PCs on the STR. I'm also using a high end PC on it, only because I had one available. I would bet it does make a difference... I'm also guessing it would be the absolutely last thing I would put money into if I didn't have an extra PC laying around. In the wild world of hifi the PC on the STR could make a significant difference... then the fuse too! Actually the fuse might make a bigger difference?

Why can it not be two DHTs?

If you get the adapters from Al, running octal 5v rectifier(s) through the STR offers an improvement too. You can mix and match to really fine tune the sound. Example 5AR4 and 5U4G.

5Z3 can be electrically identical to 5U4(G?) I don't remember which. 5U4 and 5U4G are slightly different. 5Z3 have(usually) the UX4 socket so no adapter is needed. Can find NOS 5Z3 for great prices.

I did find putting the Wave Kinetics A10U8Rs (footers) under the STR made a change for the better.

What tubes are shipping with it?

Nigel, the STL DA-512DSD-2 arrived last wednesday.  Hooked up and powered up this weekend and my first impressions are very positive.  I have it hooked to an SFDB (will hollow silver) (same 6 outlet box that I am using with my Cary 300B monoblocks).The sound stage seems bigger (wider, deeper and taller).  I am hearing music that I never heard before and the clarity and separation of instruments is darn good!  The bass is tight and fast.  I feel the music more and I am wanting to listen more....It is a keeper!  I have ordered KT170s to roll and see how they sound.  Al, as always, has been great to communicate with and immediately responsive like he never sleeps.
Bob

CA James, I am a/b ing from memory.  I have only one ZBit so the connections are not the same (one with balanced and one with unbalanced).  USB cables are about the same quality.  Right now, I favor the STL DAC but I want to make sure there is no "bias" here.  Still burning in the STL DAC and tubes so it may get better, I presume. The ability to roll tubes also influenced my decision to buy.  Not too many reviews out there.  There is one you tube comparison b/w DACs but you know how these can go.  As the STL DAC seasons, I can hopefully do a better comparison.  
Bob

I saw the same ad.  Al said it did not have a built in STR so somewhat a mislabel or misadvertisement.  Al did have one in stock (only upgrade was with side oak and so I purchased that one.  He can make one with a built STR and will be with bigger dimensions.
Bob

Hey Bob,

Thanks for the info. I’m looking forward to your continued impressions as the dac breaks in.

Randy

I decided to set up the STR-1002 to make sure that is it working.  I have it hooked up to the CSP-3 with two outputs (one to the UFO25th and the other to my Cary 300B signature monoblocks).  I am currently listening to the UFO25 and has been on for 4 hours now.  Wow!  I am not going to repeat GS's initial impressions but bottom line, it brings the UFO25th to a new level!  Volume seems to have gone up and the sharpness (clarity) have noted on the UFO25 is no longer there.  The STR gives it a fuller and richer sound and very much like how the 300b monoblocks sound.  The Altec 804-8K brightness is gone and now I am enjoying them thoroughly.  
Bob

Very nice Bob. I’m curious what rectifier you had in the CSP-3 before you replaced it with the STR?

Nigel,
Ordered but wont arrive for another week at least.
Bob

Uh oh... Canada Post says that my STR should be delivered today...

Wow. This is ridiculous. Absolutely ridiculous. I can't believe that what I am hearing is happening in my living room. Chills, goosebumps, the whole deal.

On the downside, something is rattling in the room that didn't use to rattle. Gonna have to track that down...

I had a set of 866A mercury vapor tubes and scrapped one immediately by starting the STR at 10v instead of 5v. Don't do that. No matter, the PSVANE 805A pair that came with the STR are leaving me with no complaints at the moment.

I think this is "it." I don't know what else I could possibly want from home hi-fi after this. And to think that I have a new Reed tonearm coming soon as well.

I have dinner plans in about 45 minutes and I think I'm going to have a hard time leaving the house.

FWIW, I was prepared with a dedicated SDFB for the STR, along with a Super Sluggo. I put the Sluggo in right away, so I can't comment on the difference, but I'm sure it's not hurting anything! lol

Sorry to hear the 866a yikes moment.  I plan to identify each tube’s voltage with a sharpie pen to avoid getting the voltages crossed up which is easy to do.  Also, Al advised me to calculate the wattage to make sure I don’t go above 50w cumulative on my 104 to avoid transformer excessive stress/damage.  A lot to learn with all the variables on these STR’s.

Bob, That works out, that way you can get a feel for the 805As before swapping to the 845s.

Bloodlemons, Yahoo! It will season and get better with hours too. I’m going to plant the seed for you to try the STR on the CSP too.

Bummer about the 866As, I accidentally turned on a pair of the jumbo tubes on 5v. Fortunately didn’t seem to damage the tubes.

So glad both you guys are also getting tangible improvements. After 6 weeks I’m still really happy with the STR. Finally ordered a pair of Linlai 211s.

Hearafter, Nice selection of possibilities,  looking forward to you sharing your experiences.

Now that some more people are getting the STRs I hope anything that sounded like hyperbole is now seen in a new light lol. It still is hard not over selling how much I’ve enjoyed the improvement with the STR.

James, I have.... sort of.

The way the STR works is each phase of the AC is handled by 1 socket. So If your component has one rectifier tube you need to have two of the same rectifier in the STR to be full wave rectification.

My amp uses two rectifiers in parallel. I removed both the SE Aqua IIs and put them in the STR. Sounded better with the STR. I preferred a combo of one Aqua II and the 3B22s. I liked the combo of 3B22s and 845 even more.

For the TRP DAC my goto rectifier is the EML 274b mesh. I haven't tried just that in the STR as it would be half wave rectification. And the 845s give me a sound I love.

Wait, so if a tube can handle 10v, is it not safe to run it at 5v?

OK. Good to know! Thank you!

STR-104 has arrived and right out of the box this is a winner!  I am using the 2 stock 3B22 tubes and everything just sounds better.  Headroom and bass is a definite step up.  I had to adjust my sub down.  Using it on my Torii Jrv2 along with Westinghouse OA3, Sylvania 6SN7 GTA, Philips JAN 5933(807).  Nice combo.  Plan to try 2A3 and 866a next.  The fun has just begun

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Fun glow light tonight.   Mercury Vapor RCA 866A first sighting.  Paired with a stock 3B22 they sound great together…excellent tone, very clear, detailed and airy.  Music seems to float for lack of better description.  Also, tried  an EH 2A3 with the 3B22 and they sound slightly different but very good, just not as airy with a bit fuller midrange/bass…splitting hairs here.  All sound much improved over 5UG4, 5GY4….installed into the amp.  Live music is mesmerizing.  I keep saying to myself What, How, Why?  I Look forward to hear how it sounds when some hours are logged on it. Thanks GS for starting this thread

GS- Those tubes surrounds look great…starting to look like my Supratek  preamp.  I feel like a boy in a toy store and can’t stop playing with the toys. These SR’s are tube rollers delight or curse.  So far in 2 days my fav’s are 866A/2A3, 866A/3B22, 3B22/2A3, 3B22/3B22, 5U4G/300B, 5U4G/5U4G. All sound significantly improved over a single tube in my Torii.   I tried using 2- 3B22 with the 300B and it just didn’t sound right - a bit off.  One of my 3B22’s top glowed/flickered like a fire purple. Looked concerning. Talked to Al and he said that was Ok due to different voltage running parallel  through the  adapter.  3B22’s glow more as voltage increases.  Have you used the  2 tube adapter?  Not sure I even need it with all these other choices that sound so good. I am thinking about building/adding Walnut sides on my Str-104 .  Easily done and should give it a more finished look.  Hearing is Believing! Tom

If interested, I found a positive review of the STR along with a remarkable number of tubes that might be used with it here: https://www.tnt-audio.com/accessories/space_tech_str104_e.html

Well, I'm back on (a) waiting list .

Just sent in payment for a STR-1002 Super. AL said about 4 weeks until it ships out. I got the 300B adapters, am also going to get 845 and 211 tubes.

Got my second pair of 866A tubes today to replace the the ones I fried on my first attempt by accidentally running them at 10v. Giving them a first spin right now. Very nice! Presentation is a little more laid back, but very full and lush. I think they're adding back a little of the sweet midrange I lost when I moved up to KT88s in the ZMA.

These are nicer than the 805A tubes that came with STR. I am definitely glad I decided to try mercury vapor sooner than later.

I, uh.... have no idea. Al seems to think they'll work just fine. Maybe I'll shoot him an email.

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FYI you might be interested in the type 83 tube which is a 5V mercury vapor rectifier with a 4 pin base. However don't confuse it with the 83V which is also a 5V rectifier with a 4 pin base, but is the 4 pin version of the 5V4G.