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Old 26th January 2013, 02:20 PM   #33651
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Good posts regarding relays, connectors and responsibility, Christophe.
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Old 26th January 2013, 02:26 PM   #33652
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Parasound decided differently. They refused to respond IN THIS CASE. Perhaps, they had better things to do, perhaps their hands were tied. IF there is a manufacturing defect, then the amp could be repaired under warranty. However, factory pictures of the amp show that the connector for the A21 has no latch. If a number of people had independently complained (for good reasons) that this was a problem, then Parasound would most likely respond. But apparently one instance where a customer was 'ticked off' enough to hassle the designer of the schematic, in order to get special treatment, was 'a bridge too far'.
There is more to this 'story' than one disgruntled customer.
This is sort of the dividing line where my authority ends and Taiwan takes over. I would have preferred a Neutrik, but not necessarily a latching one, myself.
When the first runs of JC-1's were put out, my late business partner, Bob Crump, had a fit, when the JC-1 that came to him did not have Neutrik xlr connectors.
My boss and he, had it out, my boss (the same guy as yesterday) noting that it was an oversight by the Taiwanese factory, maintained that it didn't make much difference, as far as they were concerned, so what's the big deal?
Well Bob Crump was assigned to make this amp win listening contests, and he knew the difference between the connectors both sonically and materially (just apply a magnet), and he threatened to quit, if his input was ignored, and that he should not tell others about the problem. Thank goodness, he didn't, and we still had him around to look over the JC-2 preamp, that would have suffered the same fate as many earlier preamp designs, if he was again ignored. This is why this is important to me.
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Old 26th January 2013, 03:47 PM   #33653
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Default Bad cable XLR ??

Assumptions will always get you ---> The assumption is that the problem is only with the amps XLR. How about the cable's XLR? You guys surely know there is a IEC dimension spec/standard for the physical XLR? Are the cable XLR pins bad or too small or worn? Thx-RNMarsh

Last edited by RNMarsh; 26th January 2013 at 04:02 PM.
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Old 26th January 2013, 03:54 PM   #33654
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May-be, you presented the problem to Parasound in a bad way, John. Like about the lack of latch on the connector, while the problem is those connectors have holes too large to maintain both good contacts and cable in place ? That is, at evidence, a manufacturing defect *if the cables are not too heavy, and cables connectors of standard diameters*.
This happens often by wear in PA systems, the only professional solution is to change the connector. Even if there is a working latch, because poor contacts.
With a brand new material, under warranty, i would not appreciate the manufacturer do not face up to its responsibilities.
SY was clear about, and his remark about latch was 'theoretical', while he said that Berhinger have XLR with no latchs, but ok for home use, that i confim.
And notice too that SY was just talking about, not asking-you any personal intervention.
So why to say "hassle the designer of the schematic" ?
Well, i believe his Boss has just to bring-back the amps where he bought them, show them the problem, and ask for a fix.
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Last edited by Esperado; 26th January 2013 at 03:57 PM.
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Old 26th January 2013, 04:18 PM   #33655
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I can't believe that with the brain power here nobody has just suggested that the XLR cables be helped out with some simple cable clips. They have some that are very inexpensive with adhesive backs that you can attach to either the amp itself or the shelf the unit is sitting on. Are we such primadonna's that we can't come up with a simple fix instead of ranting about a simple problem? Yes they should have used a locking connector, but they didn't. Now do we throw out a perfectly functional amplifier because the cables must be hanging with all the weight on the connector, would you do this yourself if you knew that the connector was not locked in place? I wouldn't wan t to lose my warranty by modifying the amp, but I would quickly get pissed enough after this happened a few times to come up with a solution.

John.If I am reading your posts correctly this is not one of your designs? Are only the JC labeled products your design, or are others using your designs without using your name to market them? I for one wouldn't blame you when somebody else tries to cut corners on a product at the manufacturing stage but wouldn't allow my name to be used if I didn't have some input on the final implementation of the product. But you also should use a little bit of tact when someone has recommended a product based on your reputation, that is just shooting yourself in the foot and not going to make you any friends here. The atmosphere is already heated enough around here with the regular invective by a few. Yes I understand that some of you do not agree with John's design philosophies or implementation, but he does get his designs out into the wild, unlike most of what we do here for ourselves. He wouldn't be asked to do a design if his products did not bring in the bacon so to speak.

Sy,
Here is a link to a simple solution. Can't believe nobody else said anything!

Adhesive Backed Wire Clips - .250" Diameter / 50 Pack : 20039
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Old 26th January 2013, 04:37 PM   #33656
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Kindhorman, please read the 1st sentence in the official A21 Parasound webpage:

Product Lines > Halo > A 21 Two Channel Power Amplifier

"Circuitry designed by legendary John Curl"
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Old 26th January 2013, 04:43 PM   #33657
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YES, I DESIGNED the audio circuitry. That is all it says.
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Old 26th January 2013, 04:44 PM   #33658
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PMA,
Yes after I posted I picked up on that fact. Sometimes as I am writing multiple replies are happening while writing a post! Sorry for that. It would appear if Parasound cared half as much about product quality as appearances that this sort of thing wouldn't happen. I be that case cost much more than the cost of a large portion of the electronics in the amplifier. This is one of those instances where we can see where the market that Parasound is directed at is mostly marketing driven. To save perhaps a dollar or two on connectors is silly. I would have a taking to with the buyer if that was my company and my companies reputation.
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Old 26th January 2013, 04:45 PM   #33659
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Kindhornman, thanks for your input. I have never seen, much less used a 'cable clip', but it appears to be the elegant solution. I have never suffered this problem, myself.
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Old 26th January 2013, 04:58 PM   #33660
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On the subject of XLR connectors.
In ANY OTHER CONTEXT, the very idea of insisting on Neutrik or locking connectors would be laughed at here as absurd and extra costly.
For decades, Parasound has made amps and preamps with 'knockoff' connectors, and before the JC-1, even the most expensive designs by me or anyone else, were with 'knockoff' connectors. It was only with the JC-series that we made a stand. The Taiwanese think we are 'nuts' to NOT use 'knockoff' connectors, and only with threats from my late business partner, Bob Crump and me, they would put 'knockoff' connectors on the JC-series too. I didn't take notice that the A-21 had a 'knockoff' connector, they all look the same to me, without close inspection. Personally, at this time, the Parasound amp that I am using, the HCA2500, uses a 'knockoff' XLR connector. I do not consider this amp the best I have ever had in my home system, but I broke the modified HCA-3500 that did sound better, by accidently spilling a cup of coffee into it. I sent it to Parasound to repair, and they ultimately threw it away, and gave me a couple of JC-1's, instead. However, the JC-1's are too powerful for my system, so I sold them to Jack Bybee, and stuck with the back-up prototype, the HCA-2500, and I am still using it today.
At this time I am designing a first class power amp (for another company) that will be rated about 250W/channel, and it will cost plenty, BUT it will have everything that I can throw at it, and I will be very happy to use it.
FOR THE MONEY, the A-21 is a very fine product, and I am proud of it.

Last edited by john curl; 26th January 2013 at 05:27 PM.
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