Looking for 5AR4 rectifier tube most like solid state

I think the current-issue Sovtek 5ar4 is not very tubey, but still pretty balanced. Compared to what I consider the best, Holland Amperex, they are a little cold and brittle. But once burned in they do not have the harshness of some Sino examples. And the Sovtek is cheap enough to try at no great loss if you dislike it. 

I have had good luck with Cryotone 5AR4 tubes. They match your description nicely - fast dynamic etc.  Unfortunately, they do not ship things out very rapidly and they are a little pricey. . 

EML 5U4G usually can be used in place of a 5AR4 and is very, very linear. You may want to look into that!

@boxsoft

That preamp should put nearly a constant load on that rectifier. So Voltage sag really isn't a concern unless the rectifier is shot.

If the power supply is properly designed (bypassed), the character of the rectifier will be very heard to discern!

If this is an older preamp it might simply be that some filter capacitors in the power supply have degraded.

The actual audio tubes in the signal path are far more important to how the preamp sounds!! What brands are in there right now?

I’m just re-reading and seeing this is about the SLP-05. I owned a similar unit with the ultimate upgrade and actually paired it with Ralph’s Atma-Sphere S-30 on a high efficiency system for a little while. Unfortunately, the preamp wasn’t a keeper for me due to the characteristics you describe. Regardless of the tubes and cables I put on the SLP-05, it felt slow and sluggish. It is colored is a very pleasing way, but I couldn’t live with what it did to the timing the way it over-colored the presentation. Best tubes I used with it to speed it up as much as possible were Sylvania VT-231 for all the 6SN7 and the EML 5U4G in rectifier position. 

Different take but you should investigate the Space Tech Labs STR. (super tube rectifier). I’ve heard it and it’s the real deal. The HIFI cave and the Decware forum talk about it with both giving very positive results.

The sonic signature of your preamp is mostly the 6SN7 tubes. Voltage sag is not an issue (I think) because those tubes maybe draw 5mA each idle and maybe swing to 10mA on full signal. So the highest plate current is about 80mA for all 8 tubes which you do not hit unless playing full volume.

The 5AR4 drops the least amount of voltage for a given plate current than other standard issue rectifiers. At that plate current it's only about 5 volts, which should not really affect the linearity of the 6SN7 tubes. Rectifiers are more carefully chosen for power amplifiers, but in preamps I don't think will make much of a difference.

Another different take, or perhaps in addition to....have you done much tube rolling with the preamp tubes?  They can be quite different from one to the next.  

@danager +1 on the space tech lab super rectifier, I own one and it makes a profound difference with my preamp. I don't know exactly why it makes such a difference, but it does, if I want it to sound more like solid state I just roll in a couple 3B22 or 3B28 tubes, if I want more tube sound I just use 300b or 2a3.

I have the Cary SLP05 with ultimate upgrade as well but don’t suffer what you are describing. I find that the Raytheon VT231’s in the gain stages gives the best sense of best solidity. To be honest, I have struggled with understanding this rhythm and pace issue outside of turntables. I have had a number of preamps over the years, tubed and solid state, and feel the Cary is not slow in comparison (recently have had Audio Research and Schiit preamps as well).

Sorry, base solidity 

Encountered this while returning a ham radio to service: Solid State Rectifier - Tube Depot.

According to the website:

This octal based solid state rectifier is a cost effective replacement for any of the following tubes:

5AR4 / GZ34, 5Y3, 5U4G / 5U4GB, 5R4 / 5V4 / 5Z4

Not only is this an inexpensive alternative, but this solid state rectifier will firm up your low end. If you have too much sag in your low end, then this is the prescription for you.

Note: Please be advised that this replacement will increase overall B+ (plate voltage) by 10-20%. If your filter caps are older than 20-25 years, we suggest you replace them before installing this solid state rectifier.

"I want to make my tube amp sound like solid state."  I think you're trolling us.

Jerry

Lot’s of interesting comments/theories.  I have five 5AR4s and three different tube amps that they can run in.  Also have a Cary 300SEI LX-20 that is SS rectified for a slight basis of comparison. IMO the cheap Sovtek 5AR4 is the “hottest” of the five. By that I mean the least warm tube-like, the Sovtek is clean, clear, transparent, perhaps a bit harsh, so I’m guessing the least V drop of all five. Try that, then try new stock New Sensor 6SN7s.  I’ve found the New Sensor tubes to be clear, clean, and more transparent than NOS tubes. I have a collection of over 200 NOS pre-amp tubes to compare with. 
 

if that doesn’t work for you, swap out the Cary pre with a SS pre. I swapped in a vintage Crown IC 150A in my big 300b/845 integrated that has a pre-in.  Made a bigger sonic difference than any tube rolling I’ve done.  The amp became more transparent with a touch of brightness or tightness on the upper mids and treble.  Don’t know if that is equivalent to PRaT.  Still trying to figure out what that means!, but it was more British, as I understand the British sound. I know what iPRaT isn’t, my dad’s old HH Scott 222C playing Black Sabbath through 15 inch single source drivers of unknown origin at full volume in the 70’s! Trying to emulate the sound of my  buddy’s HK Citation Sixteen through a pair of Dalquist DQ10s. Couldn’t get there. 

Thanks for all of your suggestions so far, and don't worry carlsbad2, it's not a troll. Here's a bit more background:

Decades ago I had a top-flight olive Naim system with Royd Albion speakers, and I discovered that PRaT is a crucial element to me, more so than tonality, soundstage, etc. I enjoy all those other things too, but not at the expense of rhythmic engagement.

I eventually started building my own solid stage power amps, and have moved entirely away from Naim gear. I still demand the same rhythmic qualities from my systems, though. My main system has the Klipsch Cornwall IV, which I love for its ability to handle fast transients and create a sense of scale and "being there". As is often the case with the Cornwall, it's up against the wall. This makes the soundstage less 3D, but again, I don't mind that too much.

One day I was listening to my system, and I felt that it was a bit "thin" sounding, and I wondered if I could scratch this itch for more tonal richness, I was strongly encouraged to get a tube power amp (or integrated), which would purportedly do a much better job with the Cornwall IV. I acquired the Cary SLI-100 integrated, and I enjoyed how it sounded. It retained the rhythmic drive that I need, while also filling out the sound.

However, it bothered me that I couldn't use the many power amps that I had built. Amongst the earlier conversation encouraging a tube power amp, some urged that a tube preamp with a solid state power amp would do just as well or better.

I tried the Cary SLP-2002 with some of my amps, and I preferred that sound, and I was able to resume with the fruits of my DIY labors. Much like the SLI-100 integrated, this preamp from Cary had strong rhythmic strengths.

Then I got the opportunity to get the SLP-05, and took the plunge. I was disappointed to discover that it sounded so laid bad. It was spectacular in most respects, but completely boring rhythmically. So now I'm trying to determine if rolling tubes will get more life out of it. 

It comes with eight Electro Harmonix 6SN7 tubes (2 input, 4 driver, and 2 headphone). I just tried a pair of EH Gold for the input tubes that I had, and that boosted things a bit, but we're up to perhaps 20% of what I want.

Some of my research has suggested that the rectifier tube will have the biggest impact on handling of transients, although some posts above refute that. Regardless, I've arrange to pickup a Mullard GZ34 5AR4 (with either the 4 or 7 notch plates, I haven't decided). We'll see what it does.

After that, I'm not sure how to proceed. I could try switching off the 4 driver tubes as well, but some comments above suggest that what I want isn't possible from the Cary SLP-05. 

I very much doubt that voltage sag is the problem with a preamp. I have compare 866a tubes with 3b28 tubes, (which only drop about 15 volts and have great regulation) and they sound different, so it can't be voltage sag.

boxsoft

First off, (before you buy anything) do yourself a favor and reach out to Brent Jessee at audiotubes.com, he is the most knowledgeable and best tube supplier out there. He can help with recommendations, and probably has experience supplying tubes for your equipment.

Great tubes are expensive. I can highly recommend the NOS Philips 5R4GYS, and the NOS Mullard GZ37....if they are compatible with your gear. The Philips is magical, and the GZ37 is really close

As others have mentioned, in most gear the 6SN7s have a greater impact on SQ. For NOS tubes (and I can recommend) the 1940s Sylvania 6SN7GT/VT-231 "Black Plates",  and 1950s Sylvania VT-231 "Bad Boy" tubes......both of these will cost you $250 to $300 per pair.

For new production, my favorite is the Linlai E-6SN7s. They can be found for $155 per pair at jjyaudio, which is a very reputable Chinese supplier

First of all, I used a Cary SLP-98P for a couple of years but I got tired of the thick, sluggish sound. I now use a 6SN7 Aikido preamp of my own build, very similar to what Don Sachs was providing before he retired from that business and moved to Spatial Labs. That in turn was based on the Tubes4HiFi SP14 octal Aikido preamp. The Aikido circuit is much "faster" and more transparent than the Cary, plenty of rhythm and pace.

Secondly, I would NOT mess with solid state replacements or different types of tube rectifiers at the risk of voiding your Cary’s warrenty or worse, damaging it. IMHO the Cary sound is determined by the way they configure the 6SN7, and also the type of output caps they use. A lot of folks like that sound but like you, I found it unsatisfying, especially once I heard the Aikido-style preamp.

You COULD try a genuine Mullard GZ34. They tend to be "faster" and a bit more lively on top than most others. A current-manufacture Chinese or Russian 5AR4 will, IMO, NOT get you what you are looking for.

If you want to keep the naturalness and linearity of the 6SN7, I’d suggest a used Don Sachs SP14, or the Linear Tube Audio MicroZOTL or the new Velo, if that’s more within your budget. Also look at the Icon Audio Pure Valve. Another option might be the Black Ice F360, which also uses the 6SN7. That’s my .02. ;-)

ETA: I forgot to mention that the Tubes4HiFi SP14 is still available, and at a very good price. It’s not as tricked out as the Don Sachs version, but it’s a VERY good preamp for the money, one of the great bargains in high-end audio IMO.

Thanks, all, for your recommendations! I’ll start with that NOS Mullard, and decide whether to continue and swap the driver tubes, or to give up and move to another preamp.

FYI, the Mullard is an F32 4 Notch dual halo GZ34/5AR4, Coded F32 B3C1 (Translates to Blackburn plant, 1963, March, 1st week).

I've had a SLP05 for a few years now (at least three, if I remember correctly) with the Ultimate Upgrade, and I love the sound of mine.  I'd go so far to say as it may have been the most significant upgrade I ever made.  Unlike you, I am not finding mine to be sweet/warm/colored . . . if anything I find it to be a tad more neutral than I might like, but the detail and imaging I hear with it in my system makes up for that (for me).

I have rolled a few rectifier tubes and I, honestly, cannot say for sure I heard any difference.  I've had a Mullard 5AR4 in there for a while now.  The tubes I've heard the biggest difference with are the two balanced input tubes.  I've had a few I liked (a pair of KenRads a generous individual bestowed on me) a pair of Tunsol VT231s I liked a lot, I loved a pair of black glass RCA VT231s for the precise detail that I thought they brought out.  At the moment I have a pair of "'52 Sylvania Bad Boys" (6sn7s)  (that were described to me as the "Iron Fist") in those sockets and as of now they are my favorites.  Another generous individual turned me on to those two Sylvanias  also gave me a pair of National Union 6F8G that he described as "The Velvet Glove" and I like them, but for different reasons than I like the "Iron Fists."  If  you decide to try 6F8Gs, you will need adapters.

Good luck.  I hope you can get that pre to do what you want it to do for you.  People have different goals and expectaions from their gear, and, as I just typed, I hope you can meet yours.  

. . . I just thought of a similar thread (questions about 5AR4 for a SLP05) a while back ago.  It may or may not be helpful to you, so I'll post a link to the discussion:

5AR4 for Cary SLP05 thread

Thanks for those recent responses. I haven't got that Mullard rectifier yet (picking it up this weekend), but someone came by with some NOS Sylvania 6SN7 GTB. That was a big boost forward, beyond the Electro Harmonix (Gold in the Input, and regular in the Driver).

It's getting closer to "good enough". We'll see if the Mullard takes it over the finish line. Otherwise, a pivot to another preamp may be required.

It’s getting closer to "good enough". We’ll see if the Mullard takes it over the finish line. Otherwise, a pivot to another preamp may be required.

Good luck in those regards.  Let us know how it goes for you.   I have read posts from both sides of the fence on that--rectifier tubes have an effect on sonics/rectifier tubes are not in the signal path & have no effect. My ears are not good enough for me to understand the differences and why I like something or don’t like something. In other words, I might be enjoying my SLP05 more than I ded before I put the Mullard in it, but I just don’t know why that is.

That might be a blessing or a curse, I haven’t figured out which.

@danager that's a really interesting piece 

that would be my first thing to try, if not just replacing the preamp, those are pretty soft and slow

@immatthewj The argument that the rectifier is not in the signal path is incorrect. The rectifier helps to supply the voltage that's used for the output rail. Noise or dips on that feed are going to affect the sound. Smoothing capacitors certainly help, but they will not eliminate all artifacts of the rectification stage.

With my solid-state Class-AB builds, I've gotten better sound by changing from a TO-220 Schottky FWB to a superior SMD Schottky FWB, so I know it's possible.

What I'm not sure of, however, is whether it will improve the handling of transients. I believe that has much to do with the unit's ability to communicate the rhythmic aspects of the music. Keeping my fingers crossed!

There is no better generator of PRAT than cannabis - in my experience. Even better - it can be "tube rolled’ by variety. This is, in effect, a modification of circuitry.

@boxsoft If it's any help to you, I have yet to find a new-manufacture 6SN7 that sounds any good to me.  Some of them actually generate measurably more distortion than NOS versions.  And with the price of good new 6SN7s today nearing $50 a piece, and given the poor quality control and possible microphonics, you're really better off buying NOS.  Some NOS tubes are unconscionably expensive, of course, but even then they will last longer and give you more listening pleasure than most of the new ones.  The problem, of course, is that searching for your *favorite* NOS 6SN7 can really get expensive. ;-)  By all means, try some different varieties in the Cary, but at some point you may find that tracking down that *one* 6SN7 that makes it listenable to you isn't worth the trouble.  A preamp more to your liking will sound good *regardless* of what "flavor" of 6SN7 you choose.  I'll be interested to see what you discover.

I think that Cary may have give you some bad information. I agree with @rhtowson; there is no reason why you can't run solid state rectifiers in your preamp. While I prefer the sound of tube rectification, there have been situations when I have used plug compatible solid state alternatives. To be honest, while rectifier types and quality (tubes) will make a difference, it's generally not a huge difference. And SS "tubes" last longer and don't change much with use.

Lots of good advise here. Try swapping tubes and/or SS devices and see what sounds and works best for you.

Yes, I was a bit surprised when they claimed that changing the rectifier would require a complete power supply redesign. I've designed power supplies for many solid state amps myself. SS rectifiers have a lower voltage drop, so the rectified voltage would be higher. Consequently, the smoothing caps would have to accommodate the higher voltage.

I guess that higher smoothed DC voltage would be passed along to any regulation circuits, and potentially require more heat dissipation. (I have no idea what's in place in the SLP-05.) If there is no regulation, then the higher voltage would be passed along directly to the rest of the circuitry.

Therefore, I wouldn't feel comfortable trying a SS rectifier without the blessing of Cary.

Therefore, I wouldn't feel comfortable trying a SS rectifier without the blessing of Cary.

Understand. But the tube plug-compatible SS rectifiers are designed to be direct replacements. I have tried them in many amps and never had a problem. They run much cooler than any tube and I haven't noticed any voltage differential, compared to the compatible tube. But maybe the Cary circuit is more sensitive???

Thanks, @br3098 . I haven't had a chance to try the Mullard yet. If I'm still dissatisfied with that, then I'll ponder whether to try a plug compatible one, or to start looking for another preamp.