Cary Audio SLP-05 First Impression

one important point touched upon earlier, which bears some emphasis, is that when a small signal tube goes bad there may be unwanted microphonics, subtly distorted music, rolled off treble, dull sound heard...

but when a tube rectifier in a power supply circuit goes bad, gear can (and often does) go up in smoke, and a repair is then needed... hear a loud pop and smelling electrical smoke come out of one’s expensive linestage is not for the faint of heart 🤣

therefore, sonics aside, to me, this is why getting a ’forever’ rectifier like a true blue old stock british/dutch/japanese 5ar4 is a must

i remember few years back, a stupid $20 sovtek 5ar4 was the most expensive rectifier i ever used, as after it failed, i had to send my modwright power supply back to dan for a $320 repair

@dger1979 

definitely a noticeable sonic difference with different rectifiers. 

Stock Sovtek- kind of bland overall, nothing offensive but nothing great

New production Gold Lion- improved dynamics but thick and veiled sound.  

NOS Amperex- Punchy bass and very good dynamics but a bit noisy on the top end.

NOS Mullard GZ34 F32- Clear, refined, smooth and excellent dynamics and improved sound stage.  

Thanks @jjss49 - great suggestion and perspective. 

anytime, in pretty much any piece of serious hifi gear...

if you see a modern russian or chinese 5ar4 rectifier, the best and most important upgrade is to change to an old stock uk/dutch/japanese or usa made one...

in a hobby where the specifics and situation usually dictates the right answer, here is one aspect that is correct and smart to do 100% of the time...

Thanks @avanti1960 - good to know.  And you hear a clear sonic difference by swapping the rectifier?  I’ll try to hunt one down is that’s the case.  Is chasing the rectifier more impactful than changing the preamp tubes?  When I got the preamp I also got 24!! Stock 6sn7 (3 x matches sets), so I’m overloaded….

@dger1979 

Just checked mine and it reads 250 / 69.  I am not concerned about it, been playing solid for almost 3 years.  

E-mail Steve at Cary, they he'll get back to you right away.  I wonder if it has to do with the tube rectifier installed.  FYI not a fan of the original Sovtek rectifier, it failed after 3 months and took out the fuses.  Look on e-bay for a NOS made by Mullard GZ34.  

I thought this group may have some insight for me.  I picked up an SLP-05 recently and sent it to Cary for the ultimate upgrade.  When I bought it the LED lights weren’t operating so I didn’t take note of the meters.  When returned, all sounds great and is functioning well, however the plate voltage is at 200 and the plate current is around 49.  Is this of any concern as the manual calls for 210/60 respectively.  

Hey @jmbumgarner01, thanks for sharing your interesting experience with the Sylvania tubes.  Something to consider when i feel the urge to do some tube rolling again.   

Also, i’ve read quite a few comments on the stock Slovak rectifier tube not lasting very long.   I guess it’s really not that well made.  

 xcool….congrats on your purchase but sympathy on the issues…ughhh.
 

Have had my SLP-05 about 2 years now and still very happy with the sound; it is a fantastic sounding preamp. If you want to tube roll on a bit of a budget here is what I did. I am currently running NOS Sylvania 7n7 using an adapter for the tube base. It was a huge upgrade from the stock tubes. You can pick up 8 of these with the adapters from JAC music in Germany for under $500 I believe and additional tubes are very reasonable. I am sure someone will tell me this is compromising the sound in some way but There is no doubt these are considerably better that the stock tubes. I can’t comment how they compare to the $100++ 6sn7  however. I also put an early 60’s Mullard 5AR4 rectifier in and that was a good improvement. The Slovak crap failed in month 3.

@immatthewj,  great.  thanks for sending this.  I’ll check it out.  

Good to know about your experience with NOS Mullard rectifier. Can you tell me exactly the model/year if you remember? I did change my rectifier tube to the Gold Lion Genelax as recommended by some member here, but did not hear much difference

@xcool  , a while ago I had some questions related to the rectifier tube for the SLP-05; I don't know if you caught any of it when it was running, but if not, you may find some of the replies helpful.  Or you may not--but either way, here is the thread:

The Sylvania 6SN7 GTAs from the early 50's are the best sounding tubes I have had to date including Ken Rad, RCA, Raytheon etc.  

The Sylvanias are reasonable and NOS units are readily available from reliable tube sellers on e-b.  

so I tried some JJ's I had and the whole unit changed!  And I HATE the JJ 6SN7 tubes usually!

@blkwrxwgn  , I recently had a bad experience (a way too early failure) with 4 RCA Glass VT231s that I paid way too much for in the phase gain buffer sockets (in my SLP 05), therefore I am back to the EHs in those four positions.  I intend to give Mr. Jessee a call one of these days, but for now, I kind of blew my tube allowance.  As I remember, JJs are quite affordable, so can you elaborate on the sonic changes they made in your SLP-05?

Hey @blkwrxwgn, yes I did some tubes rolling on my SLP-05.

I’m like you, I also found the stock EH a bit too bright for me. So I contacted Brent Jessee. Great guy to deal with BTW. He recommended the RCA black plates. So I bought 3 pairs to change out the 2 pairs of gain stage tubes, and 1 pair for the balanced buffer.

The RCA’s are a lot warmer which I like. It took away the top end edge, but also with it some details. The bass are OK, but it lacks some slam. I then changed the balanced buffer tubes back to the EH, and the system sounded better. It had more details without the brightness. I’ve been quite happy with that combination.

And then after a couple of months, I decided to try some NOS Ken Rad to replace the RCA at the gain stage. Most comments I read about the Ken Rad are how good their bass sound. So I bought a couple of pairs from Brent Jessee. Unfortunately, they didn’t work out. There were so much microphonics literally 2 minutes into the music that it was completely unlistenable. So I returned them and just kept my RCA’s.

A few months ago, I decided to give the much raved about Linlai E-6SN7 tubes a try. So I bought a pair to replace the EH at the balanced buffer stage, and I like it quite a bit. Better sound stage and tighter and lower bass.

So this is where I am now with my tubes, and probably live with it for a while.

Good to know about your experience with NOS Mullard rectifier. Can you tell me exactly the model/year if you remember? I did change my rectifier tube to the Gold Lion Genelax as recommended by some member here, but did not hear much difference. Also, let us know how the Sylvania work out for you after you burn them in.

Hope this helps. Cheers!

@xcool did you ever try different tubes?

I just got an SLP-05 (used older one) and it came with newer stock EH tubes and I really liked the sound BUT it was a tad bit bright and harsh sounding so I tried some JJ's I had and the whole unit changed!  And I HATE the JJ 6SN7 tubes usually!

I then put in a pair of Sylvania 6SN7 VT231 tubes in the 3 and 6 spots and got even better sound.  I'm now waiting on some Sylvania tubes for the 1,2,4,5 spots.  Also swapped out the JJ rectifier that was in mine and put in a NOS Mullard and that was probably the best upgrade of them all.

You HAVE to roll the tubes in this unit, it's beyond worth it.

That was a well written update.

Thanks @decooney ​​​​@rodman99999 for the tube rolling suggestions.   I guess I will stick with the stock tubes for now, but I'm sure eventually I will be looking for some new tubes.  That should be an adventure of its own.  😀

As with "everything sounds louder",  all I'm saying is that when the volume increases,  the top end, mid range, and bass all naturally sound louder, and the brightness becomes more noticeable and less tolerable.   

Anyway, my listening area is pretty small, and I sit fairly close to my speakers.  My average listening level is around 60's in decibels.  I rarely crank it up pass the 70's. My power amp is a Parasound JC5, and given my listening level,  I don't think it's a power issue.

       OH, and if you do start buying tubes to roll: be certain whatever you get are tested and certified (if not guaranteed) to be VERY low-noise.

                                             Enjoy your jams!

@xcool -

      You mentioned everything sounding, "louder" and, I'm guessing: edgier (maybe)?

       If the amps and speakers you're using were addressed already, sorry, but- if, when you, "crank it up", your presentation/soundstage doesn't get bigger (as opposed to louder)  while remaining clean/distinct and tuneful: you may be running out of power, before your SPL thirst is sated.

                                         Just something to consider.

       Far as tube rolling: here's some 6SN7 tube info, many have found helpful:

                                http://www.dehavillandhifi.com/6sn7_vt.htm 

          https://www.head-fi.org/threads/the-reference-6sn7-thread.117677/

                                    http://www.audiotubes.com/6sn7.htm

Glad you got it fixed. Now about the bright sound.  Refer back to page-1 of this thread. There is a reason three different people chimed in about the stock EH 6SN7 tubes. This is where you indicated the following about replacement:

@xcool "I’ll keep your EH 6SN7 suggestion in mind. I’m sure I’ll get that itch one day to try out some tube rolling, but I know very little about it." 

For now, It may be best to simply enjoy it for a few hundred hours. See if it settles down some more. If not, refer back to page 1. My EH6SN7s have been in the Cary preamp box since the first week I owned it. Spare test tubes at best. Bright, grainy. 

Hmm! Not sure that would gel well with my current thought process of just work as intended. I would be to worried about the rest of the build quality, especially seeing 2 issues in the first 3 months of ownership but if one is willing to stick it out, its a least good to see them stand behind there product.

Now get to some music!

Hi folks, I just want to post an update on my SLP-05 that was sent back to Cary for repair. I finally got it back this past weekend, and I’ve been playing it everyday and so far so good. Everything seems to work fine without a hitch. I hope this would be it. If you’ve been following this thread, you probably know that this was the second time I sent back my unit. The first one I received had a missing LED light, and Music Direct sent me a replacement. This second unit had 2 problems and I ended up sending it to Cary for warranty repair at my own expense.

Anyway, there were 2 problems with the unit. At first I thought they were related. Turned out that they were not. Here are the 2 problems and what Cary Support found and did for the repair:

The first problem was simply no sound coming out of the unit, and abnormal readings on the meters in the power unit. During troubling shooting with Cary Support while the unit was still in my possession, he noticed my tubes were not inserted fully into the control unit. Indeed he was right. I followed the instruction sheet of not forcing the tubes into the unit to avoid breaking the tube. So I stopped as soon as I felt resistance. Turned out that there was a good 1/2 inch of travel more to go. Anyway I managed to inserted all of them all the way into the unit, but that did not fix the problem.

The second problem was discovered during trouble shooting. Cary Support advised me to try different inputs. I have 1 balanced and 1 unbalanced inputs. So I moved them both to different inputs on the unit. My unbalanced input was moved to Aux2. As I switched input using the input selector to Aux2, the control unit would power off by itself, and when I switched out of it, it would go back to the power on sequence.

For the first issue, Cary Support was unable to reproduce it. The first thing they did after receiving my unit was to plug in all the tubes and played the unit. The unit played fine, and the meter readings were at normal range of 240 VDC and 60 mA. I could not believe it. After some back and forth email exchanges with Cary, the only difference I could come up with was that I did not unplug all the tubes first before reinserting them all back in properly. I simply pushed them all in one by one. Whereas when Cary received the unit, all the tubes were removed and packaged separately, so they had to reinsert all of them. Regardless of the difference, I tried to push for an explanation on why I was able to play the unit for 3 straight weeks with improperly seated tubes, and all of a sudden it just stopped working. Finally, the answer he gave me was ‘No idea!’, followed with some other explanations.

For the second issue, they indeed found an issue with one of the soldered joints, and this is what Cary wrote on my RMA in their RMA website:

"Inspected unit and was unable to replicate customers stated issue of incorrect meter readings. Confirmed customers stated issue of unit turning to "not ready" when AUX 2 input was selected. Inspected input boards and found the cold solder joint for the AUX 2 relay in the left input board. Corrected diode orientation and unit is functioning correctly with meters reading ~240v and 60mA. Reflowed solder on 12v filament regulators in power supply. Unit is set for burn in and will perform final qc in the morning."

I don’t quite understand everything above, and I tried to get a better understanding of what was wrong and why they have to ‘correct diode orientation’ and ‘reflowed solder on 12v filament regulators’, and all I got was some general answer on some regulations in UK that require using solder without lead, and lead free solder requires higher temperature to get a better joint.

Anyway, this would not make an interesting story without any surprise, would it? So here it is:

On the day that I thought Cary would be shipping my unit back, I got an invoice in my email for $310, which included $110 bench fee, $30 RMA administration fee, and $170 for shipping the unit back to me. WTF? Needless to say, I was furious. I already paid for shipping going there, and they are now charging me for something that should be covered under warranty. I immediately email Cary Support, and his reply to me was:

"Yes it would be covered under warranty, but there’s nothing wrong with it. We just spent 3 days and a great deal of time proving the unit is not defective. I agree that if the product is defective we would make the repairs under warranty. We stand behind our products. This is not the case."

So I sent him the comment that was written in my RMA that clearly stated that a soldered joint was bad, and then I didn’t hear back for a good 3 or 4 hours. He apologized and said there was a technical issue with their RMA website, and they will be shipping back my unit with no charge. Problem solved.

So, here are my thoughts on this whole experience:

For the first issue, an answer of ’no idea’ is simply not acceptable. I don’t expect the support team to know everything, but I think the proper thing to do is to file an issue ticket to engineering team, and have them reproduce the problem and perhaps make appropriate design change, or at the very least, issue a new FAQ to help customers address this issue without having them shipping the unit back. Also, improving the setup instruction sheet would also be helpful. To be fair, I don’t know if support had contacted engineering team or not. Maybe this is part of their process. If so, it would have been nice to let me know that engineering team is looking at the issue, instead of a ’no idea’ answer.

For the second issue, it makes me wonder why this wasn’t caught before the new unit was shipped to me. Did they not do proper QC testing before shipping? I didn’t raise this concern with them, maybe I should have. It is entirely possible that I would have never come upon this issue if I wasn’t trouble shooting my first issue. I simply never did bother switching my input to Aux2. It would have been a bummer had I finally found this issue after warranty has expired.

As with the issue of the invoice. I accepted that it was an honest mistake, but the answer I got back really made me think hard on how Cary treats their customers. Do they really think that I’m happy to spend $150 to ship a perfectly functioning unit back for no reason? In the case of the first issue, I agree I bear some responsibilities of making sure the tubes are all inserted properly, but I also can argue that the instruction sheet was insufficient, and they were unable to help me resolve the problem while the unit was in my possession. To charge your customer for what could have been a warranty repair, even though it was a setup mistake just doesn’t seem right to me, especially for a product at this price level. That says a lot about how much do they care about customer satisfaction vs how much money they can squeeze out of their pockets. At the end, this was resolved as it should have, but it left a bad taste in my mouth.

Anyway, that’s the whole story. I am not trying to trash Cary’s reputation. They do make an awesome product, and I guess most customers are happy with their support. FWIW, the support person I’ve been dealing with are mostly pleasant to deal with and very responsive on his replies, although I don’t always get a straight answer from him. I’m only sharing my own experience, and it might very well be an isolated case. I'm just happy I’m getting a fully functional unit back, I hope I don’t have to report back for any new issue going forward.

Finally, just one more thing about the sound quality. I remember I could barely contain my excitement when I had my first unit for less than 48 hours. I still do like the sound a lot, but I wish the top end can calm down a little. One of the strengths of the SLP-05 is the mid range, it really makes the vocal to stand out and makes it sounds like you are listening to live music. Occasionally, I find it a bit bright at the top end, especially with female vocals. The unit sounds great at low volume with all the details, but when i crank it up, everything sounds louder which includes the top end, and that can be a little much for my old ears with tinnitus. The unit has about 300 hours of burn in at this point. I wonder if the top end can still continue to calm down with more time on it, or if I can address this with some tube rollings. Feel free to give your thoughts on this.

Thanks for reading.

"Little darling, the smiles returning to the faces…" -- George Harrison

and no way should the consumer bear additional costs to rectify a manufacture defect.

@testpilot  I totally agree with that.

The “Ultimate Upgrade” is a regular factory authorized option and should not be considered a special order with limited consumer rights and/or warranty.  MD is a Cary authorized agent, therefore, it is their responsibility to deal with the manufacture, not the consumers.  This is a MD problem, not the consumers and no way should the consumer bear additional costs to rectify a manufacture defect.  

@immatthewj Yep, same guy and thread with that other preamp. A 1 of 500 kind of issue that finally got resolved I gather. The V12R is a little different beast. Larger main transformer, runs different f/e tubes instead of 6922, 12Bz7 TV tubes Dennis liked years ago. No need for all of that, a standard V12 with really good coupling caps, hexfreds, and good input tubes can be very nice. Since you bring it up, there was a revision I found of the oper manual that did not get updated on the published link. My tech shared with me and the former designer (after DH) concluded running 280ma per side was ridiculous, and no need to go above 200ma per side, it will help save your tubes, fuses, and transformers and still sounds great. Enjoy.

@decooney  don't get me wrong--I think my SLP05 is a great sounding unit and it certainly is a sexy unit.

The thread that I was thinking about involved an issue with a Cary product (and I don't remember which one for certain) that went back & forth to & from Cary, as apparently, for that service order, Cary's right hand wasn't talking to the left hand  (one tech thought that a previous tech had replaced a cap and etc). . . .

I guess my experiences with Cary Audio in the '90s made me somewhat spoiled.  All the Cary products I bought back in that era were solidly reliable and the tech support was via telephone ad personal.  However I do realize that nothing stays the same forever. 

A V12R?  I have one of the earlier V12s and I love it.  It's been a great amp.  What all did they do to the 'R' model?

@decooney  if that is the same thread I remember reading, that certainly was not a ringing endorsement for Cary Audio.  As a relatively new SLP05 owner, that made me shudder and also made me think, "Gee, I hope I never have to send mine back."

Thanks @decooney,  that makes sense.  Hopefully they'll do the right thing.  I would hate to go thru this again.

@xcool  sounds like you've covered the bases and taking the next steps for resolution.  After its fixed, since you've been through this twice on two units, I'd suggest that you push them to hang on to it for 3-4 more days longer, turning it on/off, letting it run all day, thoroughly testing and validating it before shipping it back to you. Seems like a PITA right now but it will pay off w/this extra step.  

A member colleague on another site had a triple round-trip on a different preamp that had a chronic issue and finally got it resolved. He loves the unit now, but it got pretty dicey there for a while til multiple parts got replaced inside.  Hang in there.  

Thanks @avanti1960,  I sure hope they'll do a good job fixing my unit!   

BTW @decooney,  I took your advice and reached out to the support person at MD that's been handling my case.   She told me they will extend my try out period by the number of days my unit is out for repair, and if Cary can't fix it properly, or if there are other issues after I receive the unit, they will still take it back.   I think that's great customer service!  Much appreciated!

xcool,

it was a single component in the power supply box, a power supply regulator or something like that.  

yes i saw the video, mine did not have the source issue.

they will fix it.  

@decooney,  thanks for the suggestion!   At this point, I don't have the appetite to keep trying different things.   I think I'm just going to get this thing shipped out to Cary this weekend.   Will definitely update you guys when I find out what the issue is.

@jallan, thanks for the info.  I hope you're right that it's a small issue.  I hope that whatever the problem and the fix is, it won't affect the overall sound quality, and I also hope to regain some confidence on the long term reliability of this unit.

@jsal3689, thanks for sharing your story.  Good to know that Cary cares about their customers.  I've been listening to my Parasound JC2 this past week, and realize I still enjoy the sound.    It's definitely more laid back than the Cary, but very easy and comfortable to listen to.   I don't plan to sell my JC2.  I like to keep it for varieties.

@avanti1960, thanks for sharing your experience.   Do you remember what was your problem in your case?  I don't know if you saw the video I sent in one of my previous posts, it showed how the control unit just powered off when I switched to a different source.  That seems super weird to me.  I wonder if it is caused by the same issue.

Thanks again to all you guys for your comments and suggestions.  At the very least, it helps to calm my nerve a little.  😀

Sounds exactly like what happened to my SLP-05- none of the left 6 tubes would fire and the meter readings were way off.  I had to send it in and it was fixed perfectly.  

As a last ditch effort before you send it in you can try a new rectifier- it is good to have one on hand as a spare regardless and they are not expensive.

I had a rectifier blow (the cheap Sovtek) and it took 2 fuses.  Replaced it with a NOS mullard off label and sound and reliability improved.  

I love my SLP-05. I had a Parasound JC-2 that lacked that certain something. I looked at Cary and actually conversed with Billy Wright, the owner. Ended up with the SLP-05 with all of the upgrades. The Carydirect pricing with a nice trade in value for my Parasound sealed the deal. The fact that the owner took time to send multiple e-mails told me they really care about their customers. I have two Primaluna Dialogue 7 monoblocks that really improved with the SLP in front of them. I have since bought a DMS-700 Streamer/DAC. Cary is great company. American manufacturing done right!

Also, I rolled tubes to Psvane SE Tennis ball tubes. Added punch without brightness. Great upgrade.

Anyone compare the cary to a vac or shindo ?

I bought a Cary SLP-05 with ultimate upgrade used last summer. I have the older version with the indents for the feet, and used the units stacked.

It really is an awesome preamp, with the rounded tone so notable with the 6NS7 tubes. I am running stock EH new factory tubes, but a NOS Philips red base 5AR4 rectifier. I have used it both unbalanced and balanced, with little difference noted other than more gain and perhaps a little quieter.

 My unit shows it is drawing only 30 mA too, but it works and sounds great. I researched this issue on the web and came across that if the meter isn’t wired correctly it will only show 30 instead of 60mA draw.

If you open the unit up, it’s very robustly built. There could be a bad capacitor somewhere, maybe a bad rectifier tube. I don’t see why a local shop couldn’t fix it equipped with little more than a voltmeter. I would not sweat it, it’s probably an easy repair.

@xcool if its a long ways to ship it back to Cary Audio, seems like it would be easier/faster to have a local shop tech test all eight 6SN7s and your 5AR4 rectifier tube for you.  Depending on what city you are close to, there are usually audio/electronics people around or guitar amp people with tube testers around.  ID your city and you may have someone near you on this forum or AudioCircle, or AudioAsylum / TubeAsylum. Toooob Heads are everywhere or somewhere in a basement geeking out on their tooooobs and testing equipment. LOL Hahaha.  

The fact that the current was at 30 mA, and not the normal 60+ mA seems to suggest to me that the tubes are not drawing enough current, and are possibly malfunctioned.  Then again, what do I know.

or, I was thinking, something wrong and not providing the current.  But, sadly, this is above my pay-grade.

Hey @immatthewj,  FWIW, the possibility of the rectifier tube went bad was one of the discussion points I had with Cary support.   He initially was going to ask me to open up the power unit to check the rectifier tube.   Later on he decided that it is most likely not the rectifier tube.  He said if it were the case that the rectifier tube was bad, then the readings of the 2 meters would both be at zero.

The fact that the current was at 30 mA, and not the normal 60+ mA seems to suggest to me that the tubes are not drawing enough current, and are possibly malfunctioned.  Then again, what do I know.

. . . so pressing on with my musings on this, I believe that it is the rectifier’s function to convert the AC out of the wall into the DC current that goes through the preamp tubes. So I would think that there must be an issue in that function of your pre, as you were saying that plate voltage in VDC was pegged out.  But again, there is probably way more to it than this, and I am probably way over simplifying it, if not completely misstating it. 

Something else that interests me are the meter readings:

going from memory I think that you said that "plate voltage" (VDC) was pegged out, and that "plate current" was down to 30 Ma. I really have only a less than rudimentary understanding of this subject, but I am thinking that even though preamp tubes have different functions than amp tubes, they still need to have some sort of bias control (meaning the current flow through them, which would be the desired Ma reading) like amp tubes do, and if I am correct, on the preamp it would be an auto-bias function.

But I could very well be wrong about all of that; hopefully someone will clear up my cloudy understanding of those two readings.

And I believe that they would be possibly meaning that something (damage) had occurred that created a gap somewhere (where there was once continuity) in the circuit, and the arc that they are referring to would be the current jumping that gap.

That must have been a typo on their part.  I am pretty sure that they meant "an arc in the circuit."

Hey @immatthewj, you’re right about my tubes. The 6 on the left side have no glow at all, only the 2 headphone tubes on the right side have glow. Other than that, the tubes seem to look fine to me visually.

As with how a poorly seated or non functional tube can affect the rest of the circuitry, this is what Cary support person said in our email exchange:

"A tube can cause an intermittent issue and maybe cause an arch in the circuit. Its possible that a tube may have been compromised and will need to be replaced. Hopefully that maybe all that is needed."

I actually don’t understand what it means by ’cause an arch in the circuit’. Does anyone understand what that means?

Yes, I’m just as curious as you are finding out what is the root cause here. Maybe it’s my wishful thinking, I feel that Cary will do right by me and do a good job fixing it. Will definitely share with you guys once I find out more.

BTW.  is there anyway I can visually check if a tube is bad or not?  Just curious.

Upon occasion I've had tubes that took on a strange glow or put on  lightening show when powered up; however, in your case, I think that the visual you would get is no glow at all. But other than that, not really, and the no-glow isn't even definitive, as it may well be something else in the circuit before the tubes.

I then turned the source dial towards Aux2.   It skipped over XLR2 and Aux1.  When the dial landed on Aux2, all the LED lights went off, as if I have powered off the unit, but the power unit remained on

I was actually thinking that if something happened to both tubes in sockets 3 & 6, that would end the signal path right then & there & if that was the case, there would be no output when using the balanced inputs.  However, that quote above is pretty weird, and that makes me think that this is a failure of some electrical component (resistor, cap, diode, etc) on the circuit board prior to the tubes.  I will continue to reiterate, however, how electronically challenged I am, so you can probably take my thoughts on this matter with a grain of salt. 

Looking at the bright side:  this is under warranty, and as disappointed as I know that you are (believe me, I can relate) with being unable to play with your new toy, from reading prior posts, at least you have vinyl and an operational phono-stage.

But I will be interested to know what they tell you is wrong with it.

Hey @decooney, no MD did not offer me a 30 days to resolve with Cary, but that's not a bad idea.  I might try to ask them before I ship the unit to Cary. 

As with shipping cost, neither Cary nor MD would cover it.  To MD, this is a custom order, which technically is not returnable.   To Cary, I didn't buy it from them, so they definitely would not cover shipping.   I had already asked Cary if they would replace the unit, and they said no, for that same reason.

The current thinking of the Cary tech support person is something related to the tubes, because it wasn't seated properly.   I think is probable, and I hope it's a minor issue.   But as I mentioned in one of my earlier posts,  if not inserting the tubes properly can lead to system failure, then it is a poor design, but I'm not an electrical engineer so maybe this is typical of tube pre/power amps.

BTW.  is there anyway I can visually check if a tube is bad or not?  Just curious.

@xcool will MD offer you 30 days to resolve with Cary and still issue you a refund in the event Cary cannot fix it within reason?   I ask because MD would end up sending it back to Cary anyhow.  I'd ask Cary in advance to cover shipping costs. The only other thought is to have someone test all of your tubes, checking to see if a few of them shorted out, grounding out, causing protection to trigger or something else going on there. 

Hey @kennesawjet, not sure if you’re aware, the Herron that I have is a phono stage preamp, not a line stage preamp like the Cary SLP-05.

Anyway, If I have to characterize the sound quality of the Herron, then I would say it is very neutral. It just seems to disappear from your analog pipeline. Some people might think it lacks character. I was auditioning the Herron, Parasound JC3+, and the PS Audio Stellar phono at the time. The JC3+ was super smooth, almost to a point that it’s artificial. Whereas the Stellar sounded a little too analytical to me. Herron is definitely the most neutral sounding of the 3. I kind of wanted a tube preamp at the time, so I decided on the Herron, and have no regrets.

If you have read some of my comments in this post, the positive attributes of the Cary is the details, tight bass, and the 3D-ish imaging, and it really draws you into the music.

@immatthewj,  I understand your rationale on returning the unit that is not working the way it should.  I feel bad because MD had already replaced my unit once.  They actually were going to repair my first unit, but I asked for a replacement, and they were happy to accommodate me on that.  Since this is the 2nd unit, and a custom order, they are less flexible on that.  But it's nice that they offered me the option of returning for a refund on a custom order.   You are making me change my mind now 😀

This thing with the tubes not seated properly can cause failure seems bizarre to me. If this is indeed the root cause, I would argue that it is a design flaw.   As you mentioned in your previous post, the fact the tube sockets are sunken in below the surface can be problematic.  You can't see whether your tube is properly inserted.   You can only go by feel.  Being a newbie with tubes,  I tried to be extra careful of not using too much force, worrying that I might break the tube.   I think Cary should have better documentation on how to insert the tubes.

Let's see how it goes.   Hopefully it's a minor issue.