John Curl's Blowtorch preamplifier part II

[SY]

Originally Posted by kgrlee

As you have probably gathered, I distinguish distortion/faults/evils into "detectable in Double Blind Listening Tests bla bla" and "not detectable bla bla".

So do I, but I'm not at all convinced that those tests you cite (and for which you have no data) have much, if any, audible consequence unless the results are grossly poor. Just because someone says, "Hirata Test!" doesn't mean they can correlate it with controlled listening results.

[john curl]

Dr. (professor) Hirata did his own listening tests 30 years ago.
Sorry SY, my boss tells me that your boss should not have purchased the A21, if he doesn't want or like the input connectors. Besides, he tells me that the Neutrik connectors that we use would not necessarily fit in the A21 chassis.
IF your boss bought the unit new, then it should be under warranty. He should be able to get it fixed that way.

[john curl]

Everyone, let me again remind you of the Hirata Test, that was put forth more than 30 years ago, by a Dr. Hirata. It is not an easy test to do or to make the test box to do it, but it measures SOMETHING that eludes typical sine wave testing, either single or multiple.
This is because it adds DYNAMIC ASYMMETRY to the test signal, and it tests for that, and that alone. What happens when a REAL audio signal is put through a gain stage? MOST gain stages will do OK with this test, but even I once error'd by trying to add an AC BALANCE CONTROL to a specific discrete gain stage. The Hirata box found the problem, and I removed it from consideration in future. That is PROGRESS!

[Waly]

Originally Posted by Esperado

Don't know (yet) for the 797 but i don't like NE55xxs for this reason: it is "hot" and "soft" oriented, and lacks a little both details and attack. Pure subjective and personal feeling.

Really? Others would put their ears on the line for the 5532 bass:

New Doug Self pre-amp design...

One more TDA1541A DAC

I am confused, who should I believe?

[SY]

Originally Posted by john curl

IF your boss bought the unit new, then it should be under warranty. He should be able to get it fixed that way.

He did buy it new. It's not broken, this is a basic design flaw that ought to be corrected. A $100 Behringer has locking XLRs- at the money level of the 21, shouldn't the basic connectors be of an acceptable quality level?

I'm starting to regret my enthusiastic recommendation.

[Kindhornman]

Sy,
Strike one for customer service on that preamp for your boss! Basically take it or leave it seems to be the answer. But at the same time I don't see how an XLR connector with a locking tab would let the connection disconnect from the male plug? You sure that it isn't the connector on the cable end that isn't causing the trouble? Perhaps you will have to help out your boss by changing the connectors yourself, that may be the easiest and fastest fix for such a simple problem? I guess you won't be recommending any Parasound products in the future. John I can see how a simple problem such as this can ruin your reputation even if you are not the cause of the problem. By association you are marked as a co-conspirator in something such as this. For the price that Parasound charges they should make sure that the few customers that they have are at least happy customers in such a fickle market. It doesn't seem to take much to ruin a companies stock in this industry with such simple correctable errors.

[john curl]

SY, please do not recommend any of my products again. I can do nothing to improve them when they are NOT BROKEN. (by your criteria)

[PMA]

Halo A21 is a power amplifier and really has the cheapest non-latching XLR connectors:

http://www.parasound.com/img/halo/a21_rear_big.jpg

[john curl]

You are right PMA! I hate them too!

[john curl]

No, Kindhornman, I make or at least contribute to a number of amps, I am disappointed that this connector was so 'marginal' but I have little control over 'everything'. Just the JC series, and I am going to double check those! '-)