Help and Advice Needed: Cary Audio SLP-05 Preamp RMA Disaster

@joshua43214 This is only with XLR in and XLR out.

While it might be implied here somewhere, going to ask anyhow just for grins.

Have you tried this exact same test with a different dac using SPDIF digital coax out to your Cary SLP-05 preamp - what happens?

Josh....So sorry to hear that you are beset with this rather odd situation. I am by no means a tech. In fact, from your story it I am certain that you have a better overall background in T+A than I do but I do want to share a thought. Is it possible that you have a faulty XLR where possibly pin assignments on the cable do not electrically align with the assignments of the device XLR out? Do you have a second pair of XLR ICs you can swap in just for diagnostic purposes? And have you experienced this phenomena from day one or did it suddenly pop up? I wish that Ralph would suddenly see this thread and chime in. While not a digital designer per se he certainly understands the nuances of balanced and I would be intrigued to see his reaction/response.

The RCA out on your DAC has about half the voltage as the XLR, any reason you would not use them?  

The problem does not exist with RCA input.

I only tested it with an RCA analog cable (Audioquest), not a properly rated SPDIF data cable.

I think I get where you are going with the idea since SPDIF cables are rated to have very specific characteristics.

Thanks,

-Josh

@acresverde

I did not try swapping for different cables, but I did think to verify the pins are correct.
Also, Cary was finally able to replicate the issue with their cables and gear.

@avanti1960 

Why not use RCA? Aside from the generic benefits of XLR, both the Holo May and the SLP-05 are reported to have the best output using balanced. I have found this to be true of the Holo May, but I have only listened to the SLP-05 for a few days in the 3 months I have owned it since it has been at the shop the rest of the time, so I can’t comment on sonic differences.

Also, using XLR lets me have a fully differential system from DAC through amp.

Thanks,

-Josh

@joshua43214

Post-1: "Cary is being resolute in stating that they have sold thousands of these preamps, never had this problem, and my case is unique."

Post-6: "Also, Cary was finally able to replicate the issue with their cables and gear."

Huh - confused - How so?

Were details shared about how they were able to replicate the issue?

@decooney 

Huh - confused - How so?

Were details shared about how they were able to replicate the issue?

Sorry if I was not clear.

I could feel my blood starting to boil again when I was writing the details. This whole affair has been the worst customer service experience I have ever had.

Both of statements are true:

Cary is being absolutely resolute in stating that my situation is entirely unique and caused by my "unusual" gear.

It took 3 weeks of wrangling before they finally RMA'd for the damage FedEx caused. They never issued and RMA for the signal issues, and they where only able to duplicate the issue after I gave them explicit instructions.
here is the email I sent them regarding instructions:

On Nov. 2, the day my SLP-05 came back, I emailed you. On line 3 of that email, I stated the amp would not turn on, and described the loose tube and capacitor. Near the end of that same email, I mentioned that FedEx could be blamed for damages. I did this intentionally to provide Cary Audio and honorable path to address my issue and get the preamp back.

 

I do not understand how you can say you did not know about the damage.

This is just one of the many examples of why I feel like my concerns have not been heard or have been brushed off, and is the root of why I am so upset and angry over this entire affair. Add to that, what knowledge of electronics I might posses has not been considered when making what are obviously nonsense replies.

 

If you have not duplicated the results, it is because you have not duplicated the experiment.

I suggest using the test tone I provided in an earlier email.
I suggest ensuring the voltages measured using that test tone match or exceed the ones provided for the Matrix DAC in that same email.

pin1-pin2

pin1-pin3

pin2-pin3

Matrix DAC LEFT	1.085V	1.084V	2.170V
Matrix DAC RIGHT	1.083V	1.081V	2.164V

I have attached the test tone wav file again.

I suggest not using a speaker with the sensitivity of a brick.

Note the above voltages are not far out of line with <Tech>s Nov. 18th statement "...standard line-level signal (typically 1-2V RMS)." I will not debate the validity of the statement, just point out (again) that Cary DACs are 6V RMS, as well as other standard high end DACs (the Chord Dave for example).

 

I make these suggestions as a person who not only designs and analyzes experiments for a living, but often has to duplicate the results of other scientists.

it was after that email that they duplicated the problem, and made the suggestions I detailed above.

Thanks,

-Josh

@joshua43214 Gotcha. Insufficient validation testing and shipping damage, would be frustrating for most anyone. Not the first time a combination of components, XLR, and a few things together produce a "unique" situation. It happens.

One thought, hypothetically - let’s say if Cary implements recommendations 1,2,3 above, and they now have (finally) proven the ability to replicate the issue, can test for it now, and the fix works, why would you not do it after coming this far.

Asking IF they can also test and prove suspected ground issues no longer exist. It's curious they already have these recommendations, I figure those did not come up out of thin air. Interesting. If you wanna take it to another level, send your dac too for testing. I'd bet there are other Halo DAC owners with SLP-05s out there. .

Maybe ask about the grounding questions/concerns over the phone too, before sending anything back and forth again. It’s also possible they may have challenges with testing the same scenario if they don’t have 102db efficient speakers lying around.

Your demo videos are smart. Maybe they can do the same at their end, showing you how it tests and works [with agreement] before they send it back to you again.

Best of luck.

joshua43214

Cary is being absolutely resolute in stating that my situation is entirely unique and caused by my "unusual" gear.

You’ve been through a lot with Cary and with that statement, I’d give up if I were in your shoes. I’d pack the thing up, bring it to my dealer, and politely tell him you’re invoking an implied warranty of suitability. (You might want to check if your state explicitly conveys such a warranty.) Refund or exchange, please.

If you allow Cary’s multiple modifications, you end up with product that is neither fish nor foul, but a one-off experiment. That’s not likely what you expected when you bought it.

I think it’s futile to work with a company that blames the customer.

Thanx for the heads up. Good luck to you.

Yuk, another Cary horror story.  (And I am a owner of Cary products, including the SLP 05.)

You’ve been through a lot with Cary and with that statement, I’d give up if I were in your shoes. I’d pack the thing up, bring it to my dealer,

@cleeds  , I am thinking that this preamp was probably purchased via Cary Direct. 

@immatthewj Yuk, another Cary horror story. (And I am a owner of Cary products, including the SLP 05.)

I’m a Cary Audio owner as well with three prior amps and preamplifiers with no issues, all of them with upgrades before and after purchase - knock on wood.

Have encountered many proud SLP-98 and SLP-05 preamp owners, hoping this situation could be rectified for the OP to get back to listening enjoyment. Not the first lemon story or with shipping damage though. Hopefully this can still be resolved with persistence and a few more steps or a return if warranted. 

With RCA inputs, does the volume fully mute?

An attenuator does not necessarily mute at zero setting, it is at its maximum voltage divider impedance and a 0dBFS signal can be heard. I wouldn’t consider that to be a problem.

I looked at Cary’s specs and they do not state a channel separation dB. Went to Stereophile and they measure the separation at only -75dB at 1kHz. That is in the same range as the attenuation of a series resistor attenuator at zero volume. So I think what you are seeing is the result of a sub-par separation spec and Cary knows it.

Just a few ideas for you from a person that has worked on some SLP-05’s. 
It’s possible the volume control needs to be replaced.  That should have been the first thing they tried. 
Kimber Kable has no shielding and so does have more leakage to the other channel.  Even though it sounds pretty good not having a shield does increase the issue. 
The balanced inputs on an SLP-05 can’t take much more the 2V per phase (4V balanced) ore it can overload the input tubes.  The balanced input signal is applied directly (after the switching relays) to the two tubes.  No volume control in its path so going much over 2V per phase can overload the input.  This shouldn’t cause the volume leakage but just so you know.  
The single ended inputs go directly (after relays) to the volume control.  

I would try replacing the volume control to see if that rectifies the issue.  
If that doesn’t do it I would think it’s a problem with the Kimber Kable leaking signal.  Because there is so much more signal on balanced.  Maybe moving the wiring around a bit might help. 

@gs5556 exactly, I brought this up earlier and OP went right back to justifying XLR again instead of re-evaluating this as a serious option, look for lower-gain source and preamp gain particularly with high sensitivity speakers. Try again with RCA!  

Hi Josh,

I don’t have any experience with Cary but I just got a Zesto Leto Preamp to pair with my SS Krell 300 XD Duo.  I’ve got a MHDT Balanced Pagoda DAC.

I have a similar issue, there is a hum when I use the DAC and even with volume set as low as possible still some sound.  Also some bleed over if I have another input and volume really high.  Sound wise, I like the pre and it’s pairing.  I searched forums, chats and found Cary specifically referenced for this issue.  It seems to be caused by fully balanced DAC’s and a mismatch in gain / voltage between the pre and amp.  

I got attenuators that sit between my pre and amp, they actually plug into the amp and the XLR into the attenuator.  When introduced, reduced the hum quite a bit, I could adjust the volume to about a quarter turn.  Still not a correct match but better.  My solution since I like my DAC, the Pre & Amp is to have a custom attenuator box built that has 3 different voltage / gain settings along with a bypass mode.  This will enable me to adjust the voltage / gain with different devices.  Root cause in my set up is the higher voltage / gain in the DAC which is at its best run fully balanced, signal to the Pre is hot and the Pre has a voltage / gain too high to match the sensitivity of the amp.  The mismatch creates the hum and other issues.  I could send the Pre in to have the voltage / gain / DB adjusted but even at it’s lowest setting would likely still be a mismatch.  
 

Try attenuators, sounds like you would need at least -20 db, maybe - 30 db.  If they reduce the issues, give you more flexibility on the volume control, you found and solved the issue.  Search on Audiogon, US Audio Mart and other forums.  You should find some of the threads I did that led me to my findings.  
 

Should you want a box like I’m having custom built, Pine Tree Audio is great to work, deal with.  Jesse is awesome.  

@gs5556 I saw that article when I first started looking online for others having my experience. I agree, I think Cary knows this is an issue and is doing everything they can to keep their heads in the sand. 

@harpo75 Your discussion mirrors some of what Cary has shared with me, in particular that the signal passes through the input buffer before it goes to the pot in XLR. They say that because of the "extreme" voltage, the signal is leaking into the ground plane and energizing the rest of the circuit.

But as you say, this should not cause any volume leakage, at least it shouldn't if the circuit is properly designed. So, somehow, signal on the ground plane is getting up into the plate and getting amplified.

Good info about the Kimber Kables, I did not know they where not shielded.

This just tells me they are selling a poorly designed input stage and/or a poorly implemented ground plane.

@decooney 

 I brought this up earlier and OP went right back to justifying XLR again instead of re-evaluating this as a serious option, look for lower-gain source and preamp gain particularly with high sensitivity speakers. Try again with RCA!

Not sure what you are referring to. @avanti1960 asked about RCA, and I provided an answer, not a justification. Consider also, I just spent $9600.00 on this thing, is it not reasonable to expect it to work with out compromise? There are a ton of equally good or better preamps out there that are RCA only for much less money.
I answered your question about how they replicated the issue.
I am happy to answer any questions on the subject, I am really hoping for a solution that can get me back to enjoying my preamp.

@mm1tt77 Thanks. I have considered attenuators, I have even heard some claim they improve the sound, though I expect this is from providing more headroom before clipping.

Adding an attenuator is certainly preferable to letting Cary hack in an 80% voltage reduction.

@joshua43214 I was reading an application used with Kimber XLR and one ground wire used thus allowing noise. Earlier, was attempting to understand if you only experience the noise issue with XLR only, and not with digital RCA coax. If you already stated this or someone else did, I missed it.  Agree it should hopefully work for the price you paid, however something in the chain of components is pushing capability beyond the design limit, it seems or maybe the cable is a contributing factor. I was wondering if the use of XLR was elevating the voltage somehow inherently by by design. I had gain with subtle noise in my former SS preamp and amp and defaulted back to RCA for signal, just for this reason alone.  One other XLR I tried did help some.   Just for grins, by chance have you borrowed or tried a different shielded XLR cable design with a different type ground configuration to eliminate the cable itself as a potential culprit?

i use above average silver mix rca.

never an issue.

 why do xlr? when the RCAs are better anyway

I think the OP is confused about RMS vs Pk to Pk voltages. The Cary DACs are rated at +/- 3v. This is 2.1v RMS, not 6v. The Holo May DAC has much higher output levels at 5.8v RMS. 

Yep. Reading a test on the Halo May showed this, "The May's maximum output level at 1kHz in NOS, OS, and OS/PCM modes was 5.8V from the balanced outputs, 2.9V from the unbalanced outputs."

Looking over my current two DACs and prior three units, all of them are 2-3 volts max output. The question i'd be wondering about is repeating the same test with another unit outputting 3v or less, and a different pair of shielded XLR cables. Or, put the XLRs aside and run unbalanced cables for input/outputs and start listening to music.  

I have a similar situation at the moment.

On the DAC - some DAC’s, mine is one, are designed to be used fully balanced to maximize their performance.  Mine uses two DAC chips providing the best performance.  I’ve tried mine with RCA / unbalanced out and there is a noticeable difference (shifts to 1 DAC chip).  In my system, my Amp also performs at a higher level and is designed for XLR / balanced inputs.  I can totally understand why the OP wants to maintain using his DAC balanced, he wants to squeeze every last drop of performance out of it along with utilizing it as it’s been designed.  
 

I’ve read other threads where the gain / voltage mismatch has been the culprit, specifically starting with balanced DAC’s.  
 

Josh - totally agree that you should expect the Pre to work with your current set up.   What I’ve found though, as I’ve asked prior to buying some preamps is looking at the voltage / gain settings / requirements is glossed over.  I’ve asked specific questions when purchasing and gotten blanket statements back that the pre will have no problem matching my amp and or other components in the system.  I think that’s the case the majority of the time so it’s not something generally looked at but should be.  
 

Good Luck!  Would be great to hear what the solution ends up being.  Let us know once that becomes a little clearer.  I’ll let you know how things play out with my set up. 

@mm1tt77 Try attenuators, sounds like you would need at least -20 db, maybe - 30 db. If they reduce the issues, give you more flexibility on the volume control, you found and solved the issue.

In this case, and with this type of remedy, do you find that introducing an attenuator into the signal path degrades the signal, thus rendering the whole idea and benefit of XLR connectivity to be sort of self defeating?

And, in this scenario have you truly compared RCA to the attenuated XLR approach and compared what actually sounds better to you?

My local 53 year audio shop runs a lot of AudioNote and other sophisticated brands, SET, Triode, wonderful sounding gear. He’s had it all. None of it is XLR is why I bring this up. He only believes in XLR for longer runs beyond 15-20ft in most cases, fwiw.

Hi Decooney, 

My gear sounds better with XLR’s.  That’s really driven by the design of the DAC I have and my amp.  I have tried RCA’s with both, it’s really due to the design of the gear, not if RCA or XLR’s in theory provide better sound quality.  So for me, comes down to synergy but I don’t doubt there is plenty of gear where RCA’s sound as good or better than XLR’s.  I’m not in the camp that one design is superior to the other.  I think both balanced and unbalanced designs can sound equally as good. 
 

Hi @joshua43214, very sorry to hear about your experience with Cary. I feel your pain. I also purchased the Cary SLP-05 earlier this year, and added the Ultimate Upgrade. I’ve had 3 issues with the unit within 6 months of ownership. One of the issues could have been easily caught if they had done a thorough QA testing before shipping. To make the story short, the issue was whenever I switched the input to Aux2 via the input selector, the unit would shut down. That really casted doubt in my head of the workmanship of their products.

I’m also really not a fan of their service. They try to nickel and dime you every way they can. Asking you to pay $250 for gain reduction mod instead of addressing the real issue sounds like BS to me. They refused to cover my return shipping cost even though the unit was still under warranty. I’ve had dealt with other vendors that would send me a shipping label for warranty repairs. Especially at the price point of Cary products, I expect more from these guys.

Anyway, it is true that the output gain of the SLP-05 is indeed very high. My power amp (Parasound JC-5) has a pair of input gain dials, and I was trying out different combination of the Cary output gain and the Parasound input gain, and finally settled on a very low 3 o’clock position on the Cary output, and leave the Parasound input gain at max.

Good luck with getting this worked out with Cary.

@mm1tt77 I don’t disagree, and it does vary by design where more emphasis can be placed in one direction or another. Some of my prior fully balanced dual mono amp gear offered XLR, and my current DAC offers XLR,. However after careful listening I’m using RCA for input on digital coax and RCA on output to/from the preamp to amps and it sounds more natural to me, not boosted with unnecessary voltage gain with consideration of my speaker efficiency and room. The better preamps I've tested are also low gain too. Results can vary of course. Best of luck and happy listening.

On the subject of XLR vs RCA I am not adamant about one method being better than the other. It comes down to implementation and design.

In my case, both the Holo May and the Manley Snappers are designed from the ground as fully differential. Adding RCA to these units means the signal path has to be altered from the original design intent.

On listening, XLR between the DAC and amps is noticeably better with no caveats than RCA. In my set up, XLR is better in every way, and RCA is inferior in every way. On almost all tracks, it is easily and immediately noticed.

Using RCA is a compromise I am simply not willing to consider. I paid a lot for this system, and I expect to get the most out of it.

I am in the middle of another round of emails with Cary. I will give an update soon.

I really appreciate all the comments so far. They have been helpful, useful, and on topic. I have had a presence on the internet since it was newgroups, and I have to say this forum is one of the best I have used in both the quality of the people, and the quality of the information.

-Josh

@joshua43214 On the subject of XLR vs RCA I am not adamant about one method being better than the other. It comes down to implementation and design.

In your case and components, you know what sounds and works best. The only thing that matters. Has Cary Audio stated what the allowed maximum input spec is for components plugged into your SLP-05 preamp given its current design?

Did you see this, not sure if someone brought it up earlier - JA's review of the SLP-05 and test results including balanced and unbalanced connections.  

@joshua43214 

For your info I have a Cary SLP-05 and to me the sound is so excellent it is worth making things work for you.  

Your DAC definitely has higher than usual voltage out through the balanced connections.  5.8 volts balanced, 2.9 volts single ended.  I am using (2) balanced sources with my SLP-05, a Sony HAP-Z1ES digital player (2 volts) and a Luxman D05 SACD player (2.5 volts).  I have none of the issues you describe. 

I have proven that sending the source signal through the balanced connections (in and out) on the Cary sounds much better- more dynamic and a bigger sound stage because it passes through an additional tube stage.  

One thing that I had used with a power amp that only had single ended input was a neutrik female XLR to male RCA at the back of the amp- no detriments to the sound quality in fact the sound of that amp is amazing.  

My sources sound amazing at that lower voltage level too.  

I would suggest the same kind of adaptor at the back of your DAC using the RCA connections and feed the lower signal to the XLR inputs to the Cary. 

I believe this will solve your issue and have no ill effects on sound quality and you can use your existing cables and no need for an attenuator.  

I would suggest the same kind of adaptor at the back of your DAC using the RCA connections and feed the lower signal to the XLR inputs to the Cary.

Hi @avanti1960, regarding your suggestion above, I actually had tried this same experiment and it didn’t work for me.

I have a phono stage that outputs only RCA. I was using a pair of Kimber Hero RCA cables to connect the phono stage to my Cary SLP-05. I also happened to have a pair of higher end Kimber Select XLR cables sitting around. So I decided to try that exact method that you described. Basically using a pair of RCA male to XLR male adapters. I bought the Cardas adapters from Amazon. So the adapters was fitted to the female ends of my XLR and connected to the phono stage RCA output, and the other end of the XLR cable connected to the XLR input of the Cary. When I turned the music on, I only got sound coming out of the left speaker, and there was no sound at all from the right speaker. So I abandoned the experiment and returned the adapters.

Few weeks later, I decided to try something similar again. This time I bought 2 pairs of RCA to XLR adapters. One with male on the XLR side, and the other with female on the XLR side. I paid like $15 for the 2 pairs. I figured it’s a pretty inexpensive experiment even if it doesn’t work. So I plugged them both to my Kimber Select XLR cables, and connect the phono stage RCA output to the Cary’s RCA input. This time it worked, and I can hear very nice improvement of the sound. Much more details with much better sound stage. The higher end Kimber Select cables were indeed better than the Hero model.

I was considering replacing the adapters to the much more expensive Cardas adapters, and then I decided not to do it since I like the new sound so much better. At the end, It was the best $15 I’ve ever spent on my system.

Anyway, for OP, it’s a pretty cheap experiment to try and it might work for your component. I know very little about the engineering behind audio systems, so I can’t tell you why adapting just one end of the XLR cable doesn’t work. I don’t know if this is generally true, or it is components dependent.

Anyway, hope this helps.

@xcool 

I used the Neutrik brand adapters a few times and never had an issue.  

@avanti1960,  looks like your scenario is a little bit different from mine.   From what I read on your post (excuse me if I misread), it sounds like you were going from an XLR output of your preamp and adapted that to a RCA input of your power amp.  In your case you placed your XLR to RCA adapter on the receiving end of your XLR cable.

In my case, I was going from a RCA output from my source and adapted that to an XLR input of my preamp.  So I placed a RCA to XLR adapter on the source end of my XLR cable.

Anyway, I'm not an expert in this stuff.  I was simply sharing my experience.  Cheers!

One of the nice things about the SLP-05 is that it will convert RCA to XLR or vice versa internally with out issue, and was one of the many reasons this amp appealed to me.

After much debate, I requested a refund. The owner proposed a dollar amount that I consider fair. This was complicated a bit by the fact that they gave me more than my trade in was probably worth, and sold it for less than they gave me for it.

I reached this decision based on several things:

My interaction with the Quality Service Manager is probably the worst customer service experience I have ever had. Not only was he willing to say things to me that are simply wrong, he is unable to listen to a customers concerns and address them. Having owned business' in the past, I can say I would find another role for this person or simply fire him. He is damaging Cary's brand every time he opens his mouth.

Because of these interactions, my trust with Cary is nil. If I am going to pony up nearly $10K, I expect to not have trust issues.

During the 3 weeks it was here before it got sent back a second time, every time I would turn it on, my pleasure was always tempered by anger and frustration. This is simply not the way to "enjoy the music."

I suppose it is also not a good fit, tho I didn't really have here long enough to really know. in total, it was here for about 2 weeks before the first RMA, and about 3 weeks before the second RMA over a period starting Aug. 12 and ending Dec. 14 when I requested a refund. During that same time, my lab submitted 2 grants, and 5 papers for publication of which I was first author on 1 and co-author of the rest. So not only did I not have as much time to enjoy the music as I would wish, those times I needed to enjoy the music where greatly diminished.

So, now I in the market for a new preamp.

Must be balanced.

Must have remote volume.

cost about $10K or less.

I prefer having a HT bypass.

I welcome any suggestions, tho I will probably start a fresh "need preamp advice thread" thread when I get back from vacation.

I will be gone til after Christmas, so I will reply to any comments then.

I want to once again thank all of you for all the thoughtful, useful, and enlightening comments. As I said before, in the 30ish years I have been using the internet, this forum is one of the best in terms of quality of people and information.

-Josh

My interaction with the Quality Service Manager is probably the worst customer service experience I have ever had. Not only was he willing to say things to me that are simply wrong, he is unable to listen to a customers concerns and address them. Having owned business’ in the past, I can say I would find another role for this person or simply fire him. He is damaging Cary’s brand every time he opens his mouth.

@joshua43214 , I am sorry to her that this did not ultimately work out for you. Believe it or not, Cary used to provide great tech support. I remember back in the ’90s (the Dennis Had days) they had this wonderful guy, Kirk Owens, and it didn’t matter how simple or how stupid my question was, he was always patient and provided an answer/solution and I didn’t have to email him to get it.

For what it was worth, that is what made me a fan of Cary and a repeat customer.

I had an issue a few years back with my old Cary V-12 and all I could get from Cary was an email saying to send them the amp & what their shop fees were. I wound up troubleshooting it & repairing it myself with help from a member of Audio Asylum who was generous with his time & knowledge, and it turned out that all I needed to do was replace a bad cap.

During the 3 weeks it was here before it got sent back a second time, every time I would turn it on, my pleasure was always tempered by anger and frustration. This is simply not the way to "enjoy the music."

And I can totally understand that. I used to have a pair of ARC VTM120s & one or the other would blow a grid resistor on start up often enough that I kept a bunch on hand & I used to grit my teeth & cross my fingers when ever I flipped the switches on them. They sounded great, but that lack of reliability ruined enough listening sessions that I wound up buying the Cary V-12 & selling the ARCs.

Anyway, I currently am running a preowned SLP-05 in front of the v-12 and so far/so good but I am keeping my fingers crossed. I had to think twice before I bought it.

I wish you well on your quest for a new preamp.

@joshua43214

Really glad you shared your experience. Now I am hesitating to deal with Cary Audio’s after sales support. I left a voice message on the Cary Direct sales number, but they never called back. It is absurd that they dont have a return policy if you select their factory upgrades (per the website)!

Couple Qs:

1- Am also concerned if my setup will need additional attenuator with SLP-05. My Terminator DAC has an o/p 4.6Vrms on the XLR. My power amp has a 29 DB gain. Speaker sensitivity is 88db.

2- Have you found an alternative to SLP05 ? I have similar requirements (balanced, remote, tube, ideally 6sn7)

in all fairness to Cary dealing with nearly double the recommended input voltage that the OPs DAC has in balanced mode is a tough thing to accomplish.

in fact I have read in other manufacturer’s amplifier and preamplifier manuals that input voltages of greater than 2.5 V from a source may have some bleed through even at zero volume control.

not trying to be a Cary apologist, just that manufacturers design for a maximum input voltage. if that voltage is 2X the specified amount, you may have some bleed through.

personally not a big deal and easily fixed by using the single ended output on the DAC which would have cut the output voltage in half.

Manufacturers try to design for typical nominal source voltage which is usually no greater than 2.5 volts as is the case of my Luxman DAC and Sony HAP player.  Turntable phono preamps are even much lower at ~ 1 volt output or so.  

Designing for 6 volts input sensitivity would cause other affects and compromises to the lower voltage sources and affect their dynamics and volume level.  

I left a voice message on the Cary Direct sales number, but they never called back.

@roxito  , maybe it is due to the holidays.

But I can tell you that, unless things have recently changed, they no longer offer telephone tech support.  The last time I needed tech support I had to send an email, & it took a while to get a none too helpful email back from them. 

I want to thank you all again.

Sorry to get back to this thread so late, my internet was down until last Thursday, and I have been getting caught up with other things after getting back from vacation.

I have spent much of the last week reviewing my notes and thoughts that led to my initial purchase of the Cary, and used that plus this experience to chose a replacement preamp. I chose to go with a BAT VK-33SE, I think it might synergize better with my Manley Snappers.

It is interesting to note that many manufacturers publish the rated input voltage, Cary does not. Imagine how much different my experience would have been had they published this info. They could have simply pointed at the spec, told me to find a way to meet it. I would have simply sent it back and taken responsibility for not doing my due diligence, as well as the loss for shipping and restocking. In stead, they wasted months on passing blame around and covering each others butts, and made me a very unhappy customer who will be happy to share my experience with others.

In fact, I most likely would not have purchased it in the first place because I do pay attention to details like this.

I disagree with the comments that it is difficult to design the amp to handle higher voltages - it is actually easy. One needs simply to attenuate the signal before the input buffer - the SLP-05 does this on the RCA inputs, but not on the XLR inputs. I assume this is to save on cost and complexity since attenuating both legs of a balanced signal requires well matched components. This is the reason the signal was bleeding through at zero volume.

The source of the cross talk, and why the signal bleed affected the right channel more than the left is from a poorly located capacitor, and Cary was able to cure this by relocating it.

These are two separate design issues, one is a design choice, the other is a design flaw in the layout of the PCB itself.
 

It is my belief that Cary knows there is issues with this preamp. Considering the review linked by @decooney above showing pretty poor performance with respect to cross talk, it is impossible to imagine they are not aware of this issue. 

Judging from my experience and others, I think Cary has lost its healthy organizational culture, and is on a downward spiral.

Thanks again,

-Josh

@joshua43214

Cary should have specified an input sensitivity spec in their manual, agreed.

However your DAC’s output voltage is exceedingly high with the XLR connections basically 6 volts, more than double the typical source output voltage. Many preamps would have trouble with 6 volts input. Included below is a note from the

manual for the Luxman CL38uC tube preamp stating the issue if input voltage is higher than 2.5 volts.

FYI the input sensitivity on you BAT is 3.0 volts, you may wind up having the same problem.

Also the full Class A circuit Cary SLP-05 is one of the best if not the best sounding preamps on the market. I have had nothing but courteous and prompt service when dealing with Cary.

To suggest that Cary’s culture is on a downward spiral because your source has 2X the output voltage than most preamps can tolerate is ludicrous.

@avanti1960    Nice try at deflection but he didn't state that Cary was in a downward spiral because his source has higher than normal output or implied anything similar. He feels they are on an unfortunate path because of the crappy service experience he had with them from their unwillingness to admit to and correct some poor design issues as well as some obfuscation issues he experienced. And, unlike so many here, he seems to actually know something about electronics which serves to help justify his assessment. I understand and appreciate brand loyalty but when you're wrong you're wrong.

That is indeed very odd Cary has placed a 1st tube stage before the attenuator. It makes for very precarious matching issues like this one. A power amp’s input stage is protected by the upstream preamp volume control, but when the preamp itself has a stage not protected by its own attenuator - ugh. A hot 6 Volt source (from XLR) is NOT too unexpected or atypical these days. ~ 5V is quite common for balanced digital DACs. The fact that the line stage nets and around 23dB of gain just further complicates system matching. And then that awkward pair of tubes dedicated to headphone amp (two 6SN7 is NOT a good driver of headphones)...

I bet it still sounds amazing in the right system, but the "right" system has to be something relatively specific. +23dB line stage with a low max-input threshold is GREAT if you have an open reel tape deck (without a separate head-amp) or a vinyl source with a super-low output MC, combined with low-sensitivity amps & speakers, etc.

My 2.5 volt Luxman CD player sounds fantastic through the balanced ins and outs on my Cary preamp.  

Although I am among those who feel that the quality of Cary's tech support has declined, I will also say that (to me) my Marantz SA10 does sound great through the balanced ins and outs of my SLP-05. 

You may want to look at a VAC Renaissance V preamp.  It is not 6SN7 based but it does balanced ins and outs, has a remote for volume and mute, and a home theater pass through.  You will find these same capabilities on other VAC preamps also, but a previously owned Renaissance V should be in the correct price range. Excellent customer service.  

@mulveling is absolutely correct. 6V balanced/3V RCA is getting more and more common, and for very good reason. My Holo May is not unique, the Chord Dave is 6V on XLR.

The Cary 200TS is 3V RCA and +/-3V on XLR
And no I am not confused about RMS, +/-3V is 6V total - there should be no debate about this. Their manual even recommends setting the output to max (3V) when using a preamp.

High output voltage on a DAC is very desirable, and it is why most companies seem to be headed that direction.

I don't want to paste a quote from the emails they sent me because I have no idea what the laws are about this (or whose state the laws would come from).

So, I will paraphrase:

The balanced signal enters the amp, and is summed by the input buffer. Even with the volume at zero, current passes through the tube and into the ground plane which is shared with the line stage. The reason the right channel was affected more than the left channel is because the right channel input buffer tube is next to the right channel gain stage, which causes a great deal of interaction with a coupling cap that is nearby.

This comment just raises all sorts of questions, whose answers are all "Ya, but it shouldn't."

The actual circuit in the Cary is like this: the signal passes through a relay, into the input buffer tube, to the volume, then to the gain stage and out to the power amp.

So signal should (in theory) pass through the plate of the input buffer, up a wire to the attenuator and stop if the volume is at zero. It does not interact with the ground plane until it passes through the attenuator.
The only way for signal to enter the ground plane is by some kind of coupling, in this case the signal was coupling via a capacitor.
So why is the signal not better protected? if it can couple with cap, then the cap can couple with it. In other words, if the small signal input can couple with and energize the line via a capacitor stage, then the line stage can also couple with the  small signal input.

Honestly, they fed me so much BS, the above paraphrase being just a small part of it, that I doubt they even found the problem. I have been under the belief from the beginning that the amp simply has a solder or flux bridge somewhere. As they kept telling me, they have "sold thousands" of these with no problem. I am sure hundreds of those are hooked up Chord or Holo DACs. I would even bet that this thread has been read by people who also have a DAC with my voltage output.
From the moment I sent my first email about it, the response was "it passed QC before be shipped it, and it is perfect." Weeks of emails, and it never seemed to get through to them that my gear is not unusual and there is probably something wrong with my unit. All they would have to do is grab another one off the burn I rack and test it.

Ask yourself, if would anyone here actually pass on to a customer the statement from a tech that "your amp has too much gain, too many watts, and your speakers are too sensitive" with regard to volume bleed through and channel cross talk?
This just screams a tech who is not able to make mistakes without serious consequences. As for the QC manager, either he is willing to feed me serious BS, or he is incompetent.

They tried one line of BS after another until they got fixated on the 6V output from my Holo May, and ignored the fact that I had to switched to using a different DAC with lower output voltage.

So yes, Cary has lost its healthy organizational culture and is a downward spiral. 

I’m not trying to throw gasoline on the fire, and I have very limited knowledge on hardware, but Cary’s comments on "It passed QC before they shipped it" is a big BS.

As I mentioned in one of my posts here, I had an issue that was very easily caught in QC, and apparently it didn’t.

I don’t want to get into the debate of the design of Cary product, etc., that is not my expertise. But I do feel that they really need to take a serious look at their QC/Support department, and think about customer satisfaction, if they want to continue to compete in this HiFi business.