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Tube audio-phoolery -- more teats on bulls

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Actually I read the article this morning and I guess this is the so called grape vine effect. The assertions made in this thread are at best inaccurate. The amplifier has 4 EL34, two 12AU7 and two 12AX7. Except for the filaments the 12AX7 are not connected, Art Dudley comments pretty forthrightly about this and dug far enough to determine that the reason is that the manufacturer uses a standard chassis and had two holes to fill. (Why the manufacturer did not cap the unused holes is a mystery IMHO.)

Jack didn't quite get the story straight.. This is a tube amplifier and has an all tube signal path. Looks quite nice too.
 
I can see them leaving the tubes with anode and cathode resistors to draw a quiescent current so they don't have to change their HT dropping resistors for mass production, but I can't image that two tubes (with sockets!) and four resistors would be cheaper than stocking a slightly larger value dropping resistor... who knows. Maybe blank plugs are expensive.
 
Actually I read the article this morning and I guess this is the so called grape vine effect. The assertions made in this thread are at best inaccurate. The amplifier has 4 EL34, two 12AU7 and two 12AX7. Except for the filaments the 12AX7 are not connected, Art Dudley comments pretty forthrightly about this and dug far enough to determine that the reason is that the manufacturer uses a standard chassis and had two holes to fill. (Why the manufacturer did not cap the unused holes is a mystery IMHO.)

Jack didn't quite get the story straight.. This is a tube amplifier and has an all tube signal path. Looks quite nice too.

I read the article twice, as I remember the Tom Carvel commercials :)

$2,999 and they can't have a new chassis stamped out?????. Even in the US you can get these things banged out and powder-coated with a high gloss finish for a couple of bucks.

If I told one of my industrial or retailer customers that they'd have to take the part with the extra holes, I would be laughed off the trade-show floor. They could have filled the holes with some Bondo.
 
What a waste of 12AX7s. I'm surprised they'd use a 12AU7 for the input stage. And that still seems a bit odd. With an extra socket per channel it would be very easy to add a direct-coupled cathode follower driver to support driving grid current. That may not be needed with the current output tubes but it would allow higher power if other tubes were ever used and would still add the advantage of no blocking distortion when the amp is over-driven. A 12AU7, 6CG7/6FQ7 6GU7 or 12BH7 would all work well for that. Just a tube and two resistors per channel, and possibly improvements to the negative supply needed. Perhaps they had that feature before and removed it thinking inferior output tubes couldn't take it? Some of the new tubes being made don't fully conform to the original specs. Perhaps someone knows what other amps they sold with that chassis?
 
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Only comment,

Bling Bling....Well why buy an amp with less tubes when you get more tubes for your money...side by side with another amp?

If you don't know they are not connected..whos going to ask in the shop?

:shhh: And I don't believe they had spare holes..

Regards
M. Gregg
 
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I'm surprised that he can hear anything above 5kHz. How old is he now?

He does the technical measurements, Art Dudley who is <warning> around my age wrote the actual review which I found to be even handed and raised valid issues about the quality of construction and overall sonic performance.

People ought to read things before they comment.

The amplifier is a very conventional design with a two stage RC coupled driver stage and parallel SE output stage with fixed bias. It's biggest claim to fame might be that review be believed it works and sounds OK, and is built right here in the U.S.A by a recent start up which IMHO is kind of cool.

FWIW I do agree that the unused 12AX7A per channel is lame.. A simple anodized plate installed from the inside would have looked fine, perhaps coined so that the top is flush with the amplifier chassis.

Mark ups by distributors and dealers in some instances can almost double the price of a product by the time it gets into the buyer's hands, and mark ups of 40% to 50% are not unusual by the dealer - ever wonder why they can sometimes afford to discount so heavily?
 
There were companies charged with fraud in the U.S. in the 60's after it was discovered that transistor radios were being sold advertised with more transistors but they just had the leads soldered together or were using them as diodes. Some 12 transistor radios still had only six acting as transistors. This should be investigated to confirm the facts, and action taken if there is fraud. Seeing tubes that don't do anything misleads customers. Marking one type of component with the type number of another of similar but different specifications may be fraud in other cases.
 
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<snip>

$2,999 and they can't have a new chassis stamped out?????. Even in the US you can get these things banged out and powder-coated with a high gloss finish for a couple of bucks.

<snip>

No doubt, it is a lot of money for a simple parallel SE amp with a 12AU7A for a driver..

I guess in high enough volumes you would possibly be right about the cost of getting chassis made and painted, in the volumes I built stuff it was not feasible at anything approaching a reasonable cost and that forced me to go to an offshore OEM for the lower cost amp line.. (Which in itself turned out to be quite a can of worms due to shipping issues - mostly damage in transit.)

I think this guy made an error in judgment from several perspectives, and I suspect he will come to realize that pretty quickly, the market will/should speak to that.
 
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There were companies charged with fraud in the U.S. in the 60's after it was discovered that transistor radios were being sold advertised with more transistors but they just had the leads soldered together or were using them as diodes. Some 12 transistor radios still had only six acting as transistors. What country are these amps sold in? This should be investigated to confirm the facts, and action taken if there is fraud. Seeing tubes that don't do anything misleads customers. Marking one type of component with the type number of another of similar but different specifications may be fraud also.


They are built and sold here in the USA, and as long as the fact that the 12AX7A perform no useful function other than eye candy has been disclosed there is no fraud. This is stated pretty clearly in the review if not quite worded that way.

A subscription to Stereophile is $10 a year for 12 issues if you shop around, so much easier to get the magazine, read the article than to speculate about what was written.

There is even a review of Thorsten Loesch's new RMA DP-777 DAC with measurements from several operating modes in this month's edition.
 
jackinnj said:
Atkinson is the "honest broker" -- like Diogenes carrying a lamp in the daylight, but more subtley if you read the measurements portion of the reviews.
I'm surprised that he can hear anything above 5kHz. How old is he now?

Assuming your question is not meant rhetorically, I'm 63. I have my hearing tested regularly and it still fall within the bounds of "normal" up to the 8kHz limit of the conventional audiologist test. However, when I test speaker impedances, I do so by sweeping a tone down from 50kHz to 10Hz at a low level. I always log when I start hearing the tone; these days, it is around 15.5kHz.

Note, BTW, that research by Toole and Olive suggests that presbycusis (the normal loss of high-frequency sensitivity with advancing years) does not have a negative impact of audio value judgements at lower frequencies. What does affect the consistency and accuracy of a listener's value judgments is low-frequency hearing loss, such as that caused by close proximity to firearms.

Thanks for reading Stereophile.

John Atkinson
Editor, Stereophile
 
Assuming your question is not meant rhetorically, I'm 63. I have my hearing tested regularly and it still fall within the bounds of "normal" up to the 8kHz limit of the conventional audiologist test. However, when I test speaker impedances, I do so by sweeping a tone down from 50kHz to 10Hz at a low level. I always log when I start hearing the tone; these days, it is around 15.5kHz.

Note, BTW, that research by Toole and Olive suggests that presbycusis (the normal loss of high-frequency sensitivity with advancing years) does not have a negative impact of audio value judgements at lower frequencies. What does affect the consistency and accuracy of a listener's value judgments is low-frequency hearing loss, such as that caused by close proximity to firearms.

Thanks for reading Stereophile.

John Atkinson
Editor, Stereophile

Thanks for sharing and yes I am surprised, considering the poor condition of my own hearing at the age of 52.
 
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