Vision phono preamp is in the house!!!!

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Wayner

Vision phono preamp is in the house!!!!
« on: 5 Jun 2015, 07:37 pm »


The new Audio by Van Alstine Vision phono preamp was delivered yesterday. This preamp basically makes a SUT useless as Frank has incorporated all of the gain and loading required for virtually any MM or HOMC or low output MC cartridge available today. Several gain options are available including 40db for MM and your choice of 54, 60 or 66db of gain for MC cartridges. The cartridges can also be loaded (via internal dip switches) for 30, 47, 100, 220, 475 and 1000 ohms.

Inputs and outputs are via standard RCA, gold plated jacks. The power supply for the unit is a 16 volt, 400ma wall wart (non-switching) and uses a jack on the back of the unit for connection. The unit also comes with the standard, thumb screw ground connection point.

After zero warm-up time, I fired up Thomas Dolby's "Wireless" LP, using my plain Jane VPI HW-19jr (with the sorbothane plinth dampers), Audioquest PT-6 tonearm and one of my AT440MLa cartridges in a Lofgren B alignment.

I have heard several iterations of this preamp before, but I was certainly caught off guard with the first LP. The sonic wall now seems to have a slope to it, with the low frequencies at my feet and the reverberant sound stage much deeper and wider then heard before, ever. My newly constructed (and calibrated Vu meters confirmed uniform output between the channels) and that was evident due to the excellently centered sound stage. The second LP was from Dead Can Dance's Into The Labyrinth by Mobil Fidelity Sound Lab. One of the passages on side one (The Wind that Shakes the Barley) always sounded overloaded from Liza's powerful voice, but the new Vision walked right thru this where my other phono preamps all had produced the highly modulated parts of her vocals as an over-modulation (either from microphone or other) saturation. I thought it odd that MOFI would let this pass, but as I now realize, it was the failure of my other phono preamps.

I am also experiencing a more natural presentation of the music, and I supect its due to the fact that the RIAA EQ is more correct. The highs are not bitting, nor is the bass bloated as I have previously experienced with other pres.

It is a really nice addition to Frank's family of products.

Wayner
« Last Edit: 8 Jun 2015, 04:01 pm by Wayner »

dB Cooper

Re: Vision phono preamp is in the house!!!!
« Reply #1 on: 5 Jun 2015, 08:38 pm »
Excellent.

I know Frank has brushed this idea aside before, but that chassis size looks like it would be ideal for a headphone amplifier. He's expressed reluctance to do it because "it would cost as much as one of [his] solid-state preamps" if I remember correctly, but consider this: In today's "deep-end" audio marketplace, people are paying that much and more for headphone amplifiers. The headphone area, in fact, seems to be the one area of high quality audio that is actually experiencing solid growth. I bet an AVA headphone amp with a gain switch (to accommodate the big differences between various headphones out there) and low output impedance would sell. I hope AVA revisits the idea. They have the box pretty much ready to go.

heiba

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Re: Vision phono preamp is in the house!!!!
« Reply #2 on: 6 Jun 2015, 08:22 am »
What is the recommended MM Grado cartridge load these days?  Different than in the 80's if you read the "Audio Basics" newsletter? In those days it was best to use a resistor (can't remember the value) in parallel with the standard 47 KOhm resistor.

Ola
Norway

avahifi

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Re: Vision phono preamp is in the house!!!!
« Reply #3 on: 6 Jun 2015, 11:39 am »
Grado changed the design of their cartridge coils sometime after that old recommendation for a 10K ohm load was made.

Modern high output Grado cartridges work just fine into a standard 47K ohm load.

Frank

Otis

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Re: Vision phono preamp is in the house!!!!
« Reply #4 on: 6 Jun 2015, 01:57 pm »
Excellent writeup Wayner, thanks.

Otis

Wayner

Re: Vision phono preamp is in the house!!!!
« Reply #5 on: 6 Jun 2015, 02:15 pm »
I forgot to mention that all cartridge settings are done internally via dual 10 position dip switches located on the board. There are instructions for setting the switches on a label affixed to the inside of the removable cover. The switches are arranged into groups to control for either MM or MC operation, gain settings and loading. You have to remove 4 screws to remove the cover (please disconnect the power when doing so), but no need to worry about stripping out sheet metal as with all AVA products, the screws go into captive threaded inserts.

'ner

avahifi

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Re: Vision phono preamp is in the house!!!!
« Reply #6 on: 6 Jun 2015, 06:12 pm »
The instruction manual/label on the inside of the cover also provides cabinet damping.  :)

Frank

Scroof Neachy

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Re: Vision phono preamp is in the house!!!!
« Reply #7 on: 6 Jun 2015, 06:30 pm »
It's sarcastic comments like the above that keep me from buying an AVA product.

PSB Guy

Re: Vision phono preamp is in the house!!!!
« Reply #8 on: 6 Jun 2015, 06:56 pm »
It's sarcastic comments like the above that keep me from buying an AVA product.
That's just silly. You don't know what you're missing.

Cornelis

Devil Doc

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Re: Vision phono preamp is in the house!!!!
« Reply #9 on: 6 Jun 2015, 10:22 pm »
That's just silly. You don't know what you're missing.

Cornelis
It's more than just silly, but we won't go there. :lol:

Doc

Charles Calkins

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Re: Vision phono preamp is in the house!!!!
« Reply #10 on: 6 Jun 2015, 10:23 pm »
It's sarcastic comments like the above that keep me from buying an AVA product.
  Hey Bro!!! If you buy one of Frank's excellent products and you don't like it you can send it back to him. No questions asked.
  Can't beat a deal like that. But I'm very sure if you did buy one of his products you would NEVER!!! send it back.

                                                      Cheers
                                                     Charlie

Minn Mark

Re: Vision phono preamp is in the house!!!!
« Reply #11 on: 7 Jun 2015, 01:47 pm »
Scroof might like it ( the AVA Vision phono) better if it came in a 60 lb billet aluminum case with no captive power cord....

 :duh:

minn mark

PS- I remain quite happy with my inboard MM version of the Vision phono in the AVA Insight+  pre-amp in my system.

avahifi

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Re: Vision phono preamp is in the house!!!!
« Reply #12 on: 7 Jun 2015, 01:57 pm »
Hey!  The Vision phono preamp does not have a captive power cord - it plugs into the chassis.

Well - -  of course it is captive to the wall wart power transformer but I don't recall seeing many of these having IEC input and output jacks.

Frank

sfox7076

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Re: Vision phono preamp is in the house!!!!
« Reply #13 on: 8 Jun 2015, 03:19 pm »
How many volts is the wall wart? Amperage?

Mary

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Re: Vision phono preamp is in the house!!!!
« Reply #14 on: 8 Jun 2015, 03:27 pm »
Here is the spec for the "wall wart"


Product Category:   Wall Mount AC Adapters   
RoHS:     Details

AC Plug included/required:   Included   
Region:   North America   
Mounting Style:   Wall   
Input Voltage Range:   120 VAC   
Number of Outputs:   1 Output   
Output Power Rating:   9 W   
Output Voltage-Channel 1:   16 V   
Output Current-Channel 1:   400 mA   
Commercial/Medical:   Commercial   
DC Output Connector:   2.1 mm Barrel Plug   
Brand:   Triad Magnetics   
DC Output Cord Length:   6 ft   

Regards,

Mary



avahifi

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Re: Vision phono preamp is in the house!!!!
« Reply #15 on: 8 Jun 2015, 08:52 pm »
Note that the Vision phono preamp wall wart power supply is just a simple 120V AC to 16V AC step down transformer.  No internal circuits or noisy switching regulators in the wall wart.  It just moves the power transformer outside the small Vision chassis for low noise reasons.

Frank

JerryM

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Re: Vision phono preamp is in the house!!!!
« Reply #16 on: 9 Jun 2015, 01:17 am »
Note that the Vision phono preamp wall wart power supply is just a simple 120V AC to 16V AC step down transformer.  No internal circuits or noisy switching regulators in the wall wart.  It just moves the power transformer outside the small Vision chassis for low noise reasons.

Frank

That's quite awesome, Frank.  :thumb:

Minn Mark

Re: Vision phono preamp is in the house!!!!
« Reply #17 on: 9 Jun 2015, 07:11 pm »
Wayner,

Quote
There are instructions for setting the switches on a label affixed to the inside of the removable cover.
"

Any chance you can post pictures of the interior and the instructions?   Just curious.

Mark

Wayner

Re: Vision phono preamp is in the house!!!!
« Reply #18 on: 9 Jun 2015, 08:57 pm »


You should get the instructions from Frank in the form of a PDF. Call Frank for it.

'ner

Minn Mark

Re: Vision phono preamp is in the house!!!!
« Reply #19 on: 10 Jun 2015, 11:53 am »
Thanks Wayner.

M