A few months ago, bought TWO of the above mentioned preamps. ( I have 2 stereo systems) Within 6 weeks of the purchase, the power supply of my speakers burns out! I purchase and replace the power supply. Three days later, the second newly replaced power supply is burnt out! After much investigative work and heartache, I discover that the Pre amp is the problem. It is defective and puts out DC. which burns out speakers. After, testing the second unit, I find that it is defective as well, EXACTLY the same problem. I return the units to my dealer, who returns them to Prima Lune.
I received a phone call from a Mr. Kevin Deal, big cheese at PrimaLuna. Told me that the capacitors, on BOTH units had failed and the units were putting out DC. He even THANKED me, for being a guinea pig, and discovering the flaw in his units.
He offered me a pair of tubes, as "compensation" for my troubles!! What a joker!!
WOW, a pair of tubes for blowing my $30,000. speakers!!
The height of arrogance and total disregard for the consumer of his product. To all audiophiles, do yourself a favour, STAY AWAY for this brand, unless you want your speakers cooked.
TOTAL lack of quality control, MADE IN CHINA junk, what more needs to be said.
Mr. Deal, WAKE UP, and STOP selling defective products!!
If, you are using PrimaLuna, and your speakers fail, check the amp or pre amp.
I haven't had any problems with my PL Premium Dialogue integrated whatsoever. There are many various units of PL products that aren't defective. I am very sorry to hear about your issue but don't blame the whole PL line as being a defective product.
EBM Kevin may charge a little more for tubes but if you listen as to why then it may make sense. I have never had a problem with Kevin and he has always been very helpful. I know he has good and bad days and can probably get a little short with some people but being a business owner and jerked around who wouldn't. I can't answer for the original post but I think overall Upscale is a very well run business or he would have closed his doors long ago. Just my 2 cents.
I think any audio product made in China needs a very strict oversight control. Some companies go that extra mile, many more do not. There was an article written in TAS, I think, many years back about all the Chinese factories and how much counterfeit product was being used, schemes drummed up with name brand products using parts of poor inadequate quality that were switched with authentic parts at the factory. The real parts were sold off on the black market. There are probably as many schemes as one could think of, if there is not enough time, money or correct people put into quality control. I feel bad for you as I myself have Line Magnetic Audio gear, designed and made in China. I had one bad transformer that my dealer had replaced, but I paid for shipping the amp. Is there any chance at all that your speakers were placing too much load on the amp? I had thought that may have been the problem in my case...
I have close friends who have owned a PL preamp with a PL amp in one system and PL integrated in another for several years and have had no issues whatsoever with any of them. I visit them regularly and love the sound they make. So with all due respect to the OP, I find it irresponsible to bash an entire brand based on one personal experience. That been said, my gut calls this BS, again with all due respect.
Were the units serviced under warranty? I too, would be LIVID and would not encourage anyone to use whatever brand.
As a PL user however, sounds like a rare incident. I've had nothing but many trouble free years with PL.When a problem did happen, with a 2nd PL piece, Mr Deal provided excellent support and my unit was covered under warranty, no hassles.
Even the finest equipment will have a clunker or a few in the batch. I don't think it matters where it's made.
I have to say I am scratching my head at the description of the episode here, as well as the user. There are major pieces missing from the description.
According to Audiogon, this user has started two nearly identical threads, and never bought or sold anything since the account was started in 2016?
It is difficult to know whether to take the OP seriously or not. But let’s do.
AFAIK, like 99% of all tube preamps, the PL Dialogue is capacitor coupled. The Premium version used to use Solen / SCR tin caps and now has switched to Mundorf. Both premium brands with VERY good reliability. Solen / SCR is a MAJOR OEM manufacturer under various brands and has a rock solid reputation. Honestly would be shocked to discover their premium caps failed. Same with Mundorf.
Also from what I can tell, and could be wrong, PL is using obsessively large caps, in the 10uF range. The original CJ PV 10 used 2uF coupling caps. This in theory improves bass response, in practical terms is probably meaningless, but it’s not evidence of PL cutting corners at all.
Personally not a huge fan of the sound of either.... but I am 100% in the minority there. :)
My point, if what I believe to be true is true then the PL DL uses premium coupling caps that in terms of reliability are not easily improved upon.
I would say Kudos to PL and Kevin Deal. I'm on the fence between 2 preamps and the Prologue premium is one of them (I'm going to start a thread about my choices). The dealer returned the preamps to PL and the Distributor (Kevin) actually called to follow up and send a nice set of tubes for your trouble. I say that is great service. I know you were out parts for your speakers (not sure the cost) but any other major mfg would not offer anything. Would McIntosh offer anything? I doubt it. 99% of manufacturers would not even acknowledge the issue in the first place. This tells me Kevin is seems quite honest with nothing to hide. Just my opinion
Tough call on a tough situation, if I had purchased 2 preamps and within a few weeks, one went defective and damaged a very expensive pair of speakers, then the second unit did the same thing, I would also be beyond aggravated. I would expect the dealer to make an insurance claim or something. A customer should not be out of pocket for what is admittedly defective goods and 2 of them no less. I'm not after a Kevin bash, I don't know what all he offered, but a set of tubes wouldn't cut it for me..... I would want 2 working preamps, a set of tubes and my speaker repairs at a minimum. Again, to me this sounds like it should be an insurance claim and the manufacturer, distributor, dealer or combination there of should be taking care of this customer. I know of PL owners myself that are happy with their product and dealing with Kevin, but that doesn't excuse this. Good Luck
I find the OP suspicious too. A grand total of two posts, both of which are the same. Why does a guy buy a $2500 preamp to match with 30,000 speakers. What speakers are they that cost that much and have "power supplies"? What the heck is a speaker power supply? Does he mean the amp portion of self-powered speakers? Perhaps a power supply for some type of planars? I realize this is fairly inconsequential, but between the lack of posting history, equipment disparity, and odd nomenclature, I am suspicious. There are thousands of PL owners out there and this guy just so happens to be the first to report not just one but two defective PL preamps. Mr. Deal is bound to chime in any moment. If the output caps were truly defective and passed DC, I would be surprised if he did not offer to do something more to assist including offering to pay the cost of the "power supply", whatever it might be-I doubt it was $30,000. I will give the OP one thing-he gave me reason to sit back and eat some popcorn.
I'd like to hear the other side of the story. I've known Kevin for over 30 years. He can be a little abrupt with some people, but he's a really good guy.
To semi-quote Paul Harvey, "Now for the rest of the story"...
Whether it is a self-powered speaker or an amp connected to a speaker, it is a bit troubling that the amp would allow dc at its input to cause high level dc at its output which would destroy the speaker.
If you have $30,000 speakers, it is incumbent upon you to do the diligence required to match upstream components BEFORE putting them in system.
And why are you using PrimaLuna components with $30,000 speakers may I ask? That does not seem like a well balanced system i.e. budget preamp paired with premium speakers. Also, the manufacturer of such powered speakers would WARN against any DC in the system that would damage them.
I don’t see how Kevin Deal is at "fault" in this case, unless he misrepresented that the preamp, or amp, had "0 DC" and it in fact had some.
And, the preamp doesn't provide DC to the speaker, that would be the amp.
I don't think this event happened. If you look at the original post, you will see that the poster said that the power supply for the speaker failed- not the speaker itself.
If we presume for a minute that the preamp was putting out DC, and that also somehow this got by the amplifier without blowing up the amp and/or tripping its protection circuitry, then it would be the woofer of the speaker that would be at risk, not the 'power supply' (which suggests an ESL, but even then the power supply would be untouched).
So without further information, I'm calling this one a massive troll- and an attack on Kevin Deal. Kevin is a competitor on mine (we make amps and preamps) but he's always been straight with me.
At least in my experience of 14 decades of audio stuff (I knew Marconi), a preamp sending DC to a power amp is so rare as to be statistically insignificant. Kevin Deal is one of the few passionately entertaining audio dealers I can think of, and it would be interesting if he chimed in here if only for my personal entertainment (sorry, but it is all about me). The part of the post saying Deal "thanked him" for pointing out the flaws in the preamps is actually weirdly personal, and utterly unlikely…I’d like to think a conspiracy exists where "special" PrimaLuna gear was sent to this guy to intentionally destroy his speakers, thus stopping an attempt at world wide domination by a French Canadian.
Well, I appreciate Ralph chiming in with some reality. I also assumed an ESL and I do know that DC from any component hitting a DC coupled input can cause serious damage in speakers. I've seen it fry speakers more than once, but I had no idea of its affect to an ESL. If the power supply on the ESL would have simply passed this on and it would have damaged the speaker, then??? I am curious to see how this plays out. I feel badly for Kevin if this is another somewhat phoney claim... Second time that I've seen that someone joined our forum just to slam Kevin and the first time, Kevin took care of the customer.
I’ve had a tube preamp pass DC to a power amp and the protection circuit in the amp would activate before doing any damage. But this still looks like a bogus thread. $30,000 speakers ?
I agree. Bogus. The thing I was thinking was maybe they were expensive speakers with built in powered subs (I know Zu has some). Plus, Isn't a preamp just an audio signal pass thru? Any power would come from the amp itself? If a Tape deck blew up, how would that effect the speaker electrically(maybe a loud noise efecting the cones themselves)?
Kevin dose not make Prima Luna gear, he is a dist for them. I agree he can be a little abrasive to Deal with (pun intended). I have purchased and used a PL Dialogue pre amp...never had a problem with it, sold it after a year and upgraded to a Manley Labs pre amp. So, I'm not sure about the OP's intent, I too find it strange that he would use PL gear with 30,000 active loudspeakers. Why would you not go directly from source to active speaker is a big question? Why use a active linestage? I find PL pre amps sound very lush and warm all the way across the audio spectrum. 2 pre amps? went bad? No!
Well we have one part of the story, and my surmise was correct, it was an ESL. But I doubt the power supply was damaged. One other part of this missive is missing- the amplifier. What amplifier was used?
So we appear to have a case of two defective Prima Luna pre-amps. Good for me that I don't consider this company anyway. I consider Lamm, Atma-Sphere, others. They don't blow the hell out of anything, as far as I know. If the speakers were indeed damaged who is going to pay for the repairs or replacement? If Keven accepted the fault should he? Yeah, one needs to know the entire chain to be able to see better. Again, who pays? George, there is a lesson for you in it - do not buy mid-level stuff, it's a waist of money and sometimes, though rarely, much more than that. We certainly would like to hear Keven speak on the matter but I am not sure it is realistic. It would not be easy for him, anyway, so if he doesn't we will understand. But..I got sort of a stutter - who pays? Still, it might be a nightmare dream, I can't really differentiate. Where is Keven? He got to help us. And George too. Who pays for what and how much?
The amplifier used was the Bryston 28B SST3 1,000 watt per channel mono blocks. Kevin asked me the same information, but the amps have been cleared, this is a PrimaLuna issue. He says that both amps have been repaired, and I should not have that problem again.
Please forgive me, if I have lost confidence in your brand.
I told him that I am not going near his products again, Chinese made equipment is PERMANENTLY off my list!
Whenever a driver blows, it is well worth checking for DC at the preamp and amp outputs prior to powering up the repaired speaker. I lost a driver in a Merlin VSM after an op amp failed to 10 Vdc signal output in the Merlin BBAM line-level bass equalizer. That DC was multiplied to the speakers by Pass Labs monoblocks that don't use blocking capacitors. It's not a common occurrence, but c'est la vie. .
This is an interesting issue. The reason I had empathy for the OP was because I had three pieces of audio equipment from a popular brand which were all defective with cheap transformers many years ago. The manufacturer would not believe the products were bad, even though he fixed them???The fan base did not believe it either, and they had not seen or touched the equipment! Were they indeed bad, or did aliens make the intermittent spurious noise, hum and sounds coming from the transformers? Yes they were bad and yes the manufacturer had not found or fixed the problem correctly. Are these kind of problems coming from a product made in China impossible to happen? I think there are some companies who make shortcuts by getting cheap stockpiles of parts, or even more likely, parts are switched at factories without proper QC. I hope, unlike many here who have outright called the OP a liar????, he gets the situation resolved. In my case, I did not, and lost a great deal of money. Don’t always believe the hype from any brand. I hope some audiophiles out there don’t buy from the company I bought from, (they are made in the USA from parts of unknown origin). Perhaps we all are too smart to make that mistake???
A 1,000 w/ch amp that does not have protection from DC at the input? To me, that would be a concern.
As to what happened with the PrimaLuna, it is something that can happen to even the best and most expensive equipment. Perhaps a bad batch of capacitors got through to the manufacturer. Sometimes the parts supplier changes the product without telling the buyers with bad results that the manufacturer only becomes aware of after several failures in the field. I had a Basis turntable power supply that failed very early and was told by Basis that a part was changed by the manufacturer without notice. Fortunately, they took care of things very promptly and with minimal hassle.
I don't know about how responsible PrimaLuna, or its distributor or retailers, is for the downstream damage caused by their product. Ideally, someone would step up and do something to make things right. But, given the circumstances, and the possibility of litigation, I can see why Kevin Deal and anyone else involved with PrimaLuna has stayed out of this conversation.
I've posted this before but here it goes again. I too had the same situation as the OP but with Threshold T2 and T400. Both preamp and the amp sent DC to the speakers. The drivers were damaged in both speakers (Snell Type b's). Threshold paid to replace all the drivers at the time (1995?). I believe the design flaws in the T series were the reason Threshold went under. I was also using Transparent Reference cables throughout the system. These paired with the wrong electronics will wreak havoc too! My current system is Classe pre and power amp. I had a pair of Transparent Reference 5 speaker cables going to a different pair of Snell Type B's. The power amp would go into standby mode once in a while. I figured it was the cables causing the trouble. I replaced all of the Transparent with Big Silver Oval's. NO more problems! Also, the volume didn't have to go as high in order to get the same sound level. That was significant. Combining gear can be a hat trick for sure. Joe
The Bryston is equipped with DC Offset protection. If the preamp made DC, the speakers would not be damaged unless the Bryston's protection circuit failed.
I'm not sure how a DC servo circuit would degrade sound if properly implemented, so it is disappointing to hear Bryston does not incorporate them.
The worst case is of course capacitor coupled, but almost all tube preamps are anyway.
Adding sensors at the output to disconnect the speakers, inputs or even turn the whole amplifier off are quite worthwhile.
DC servo circuits operate below 10 Hz. A combination servo + disconnect should be required << shrug >> but hey, I don't own a large successful audio equipment company.
The Bryston amps, as well as many other high end amps, DO NOT have DC output protection.
Usually a relay is required for DC protection, but it can be implemented by other means such as crowbar circuit (which is a means of shorting out the power supply of the amp if the DC circuit is triggered).
Because the 28B-SST's components and circuits are rugged, the
protection-circuit parameters are not as restrictive as are found in
other amplifiers. Even so, the protection circuit is designed to handle
most fault conditions, including shorts and DC offset.
It would not surprise me to find out that the above comment is actually false; that would not be a first for Stereophile. Calls to Bryston here in the US and Canada did not get me to the bottom of it. I'll try again on Monday.
Gee, could it possibly be that Stereophile routinely writes/repeats whatever market-speak they get from the manufacturer and only refute the mumbo-jumbo if JA happens to discover the discrepancy on the test bench-which is often hit and miss? But of course the main point is not the integrity of Bryston's designs or product but PL. At this point I will assume that the OP is legit since he has not retreated from his post and KD has not joined in. The OP still made some bone-headed equipment matches.
The Bryston manual is here:
http://www.bryston.com/PDF/Manuals/28BSST_MANUAL.pdf Doesn't mention DC protection circuit, though it has a soft start and thermal overload... OTOH, the manual doesn't go into specifics, except for certain turn on/off procedures, and connections.
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