AudioCircle

Industry Circles => Vista Audio => Topic started by: Audiovista on 23 Feb 2013, 04:56 pm

Title: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 23 Feb 2013, 04:56 pm
Phono-1 preamplifier has gone through some changes and now exists as MkII version.

http://vista-audio.com/products/phono-1mkII/index.htm (http://vista-audio.com/products/phono-1mkII/index.htm)

Phono-1 AudioCircle Limited Edition version (ACLE) is now replaced by Phono-1 MkII ACLE.

MkII is the former Phono-1+  (http://vista-audio.com/products/phono/ (http://vista-audio.com/products/phono/)) with the following improvements:

- user adjustable load and gain settings, by use of low noise metal film resistors http://vista-audio.com/products/phono-1mkII/settings.htm (http://vista-audio.com/products/phono-1mkII/settings.htm)
- improved internal power supply
- active offset cancellation circuit can be used to also act as a subsonic filter (set by default to 4Hz, but can be adjusted up to 16Hz) - no additional components in the sound path
- ACLE comes with the Vishay ultra low noise resistors for gain and load optimization
- ACLE will come initially optimized for customer's cartridge, and the customer can change it at any time by substituting load and gain resistors (full set of resistors comes with each preamp).
- virtually unlimited possibilities for optimization make the MkII version excellent choice for all MC cartridges (HOMC and LOMC).

- Price remains unchanged: $299
- 10% of the sales ($30 per unit) will go directly to support AudioCircle
- Free shipping worldwide (see the power supply note below)



MORE DETAILS ON THIS OFFER:

- This offer has been discussed and graciously approved by JohnR.

- Prepaid orders will be logged as received, and serial number assigned (you can pick an unassigned s/n should you want). PayPal, check or MO are all accepted.

- ACLE preamplifiers will start shipping in September '09 on the first-order-first-ship basis. We'll try to speed up the process, but it may take us 8-10 weeks to build units and close all orders.

- Standard 2yr warranty and return policy applies, with exception of actual shipping costs and $30 donation to AudioCircle which are not refundable.

- Within the US/Canada, the preamplifier ships with it's own wall plug AC supply (wall-wart). Due to the various standards worldwide 230V version needs to be locally sourced. International orders will ship without the power supply. Buyer will need to provide local power supply capable of generating 12VAC, with minimum output current of 0.2Amp and standard 5.5/2.1mm coaxial connector. Free international shipping should offset the cost of the power supply.

Here are some acceptable power supplies:
http://uk.farnell.com/ideal-power/77de-06-12/adaptor-euro-12v-0-5a/dp/2112025 (http://uk.farnell.com/ideal-power/77de-06-12/adaptor-euro-12v-0-5a/dp/2112025)
http://uk.farnell.com/ideal-power/77db-12-12m/adaptor-uk-12v-1a-multi-plg/dp/2112021 (http://uk.farnell.com/ideal-power/77db-12-12m/adaptor-uk-12v-1a-multi-plg/dp/2112021)
http://uk.rs-online.com/web/p/plug-in-power-supply/4006585/ (http://uk.rs-online.com/web/p/plug-in-power-supply/4006585/)
http://uk.rs-online.com/web/p/external-power-supplies/0459843/ (http://uk.rs-online.com/web/p/external-power-supplies/0459843/)
https://www.buerklin.com/default.asp?event=ShowArtikel(24K5495)&l=e&jump=ArtNr_24K5495 (https://www.buerklin.com/default.asp?event=ShowArtikel(24K5495)&l=e&jump=ArtNr_24K5495)


- All intellectual property, product rights and responsibilities are owned by ENG Vista, Inc., the company behind Vista-Audio brand.

- AudioCircle is indemnified of all liabilities and responsibilities in connection with this offer.

- Customer support, service and all technical queries will be addressed by ENG Vista, Inc. / Vista-Audio.

- Vista-Audio reserves the right to discontinue the offer and change number of available units at any time.

Thank you,
Boris

Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: WireNut on 23 Feb 2013, 05:35 pm
Hi Boris,

How do I contact you to place my ACLE order?
After my order is placed approx how long will it be before it's shipped?
Should I send you my cartridge specs in a PDF?

Thanks,
Steve
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: sunnydaze on 23 Feb 2013, 06:04 pm
Steve....

"how to buy"  directly from his website:

http://vista-audio.com/how_to_buy.htm

I'm sure a PM here will get it done too.

Boris is a great guy and has always been very responsive when I've dealt with him.  He'll take care of you.   :thumb:
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 23 Feb 2013, 06:26 pm
Hi Steve,

Thanks for reminding me that I did not post complete info... :duh:

And thanks to sunnydaze for linking the site.  :thumb:

Yes, you can send me a PM or email to audio@engineeringvista.com

Cartridge specs are very helpful, either link to the manufacturer's website, or PDF. At minimum I need to know output voltage and recommended loading. Knowing coil resistance also helps, as sometimes recommended loading is not the optimal one.

I do have a few preamps in stock. Can ship within 2-3 days.

Thanks again guys,
Boris
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 24 Feb 2013, 01:46 am
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 26 Feb 2013, 02:44 am
Thank you Den!

I have started topic that will keep track of orders, serial numbers and contributions to AudioCircle

http://www.audiocircle.com/index.php?topic=114482.0 (http://www.audiocircle.com/index.php?topic=114482.0)

I will also start a new topic with some thoughts on optimum settings for different cartridges. That will probably apply to all phono preamps that provide means for setting gain and loading.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: jimdgoulding on 26 Feb 2013, 02:56 am
Thank you Den!

I have started topic that will keep track of orders, serial numbers and contributions to AudioCircle

http://www.audiocircle.com/index.php?topic=114482.0 (http://www.audiocircle.com/index.php?topic=114482.0)

I will also start a new topic with some thoughts on optimum settings for different cartridges. That will probably apply to all phono preamps that provide means for setting gain and loading.
Man, please DO give us your thoughts on optimum cartridge settings.  I have a phono pre with switches for various settings and I doubt that I'm alone.  Thank you in advance.  Besides that . . what a superb deal!!  Big time.  Wow!
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: WireNut on 26 Feb 2013, 03:15 am
Hi Boris,

I just purchased a pre-owned Vista-1+ from a member here on AC and I'm enjoying it very much.
I can't adjust the gain and loading on the phono-1+ but it sounds good to me with my AT120E cart.
Great product.

Steve
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: JohnR on 26 Feb 2013, 12:31 pm
Pic:

(http://www.audiocircle.com/image.php?id=75787&size=xlarge)

 :thumb:
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: richidoo on 26 Feb 2013, 04:34 pm
I still listen to my original ACLE Phono-1 everyday, it is very good.
I am interested in trying the new opamps. Will you offer an upgrade service for original Phono1 owners?
Maybe a DIY upgrade kit?
Thanks Boris
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 27 Feb 2013, 02:30 am
Hi Boris,

I just purchased a pre-owned Vista-1+ from a member here on AC and I'm enjoying it very much.
I can't adjust the gain and loading on the phono-1+ but it sounds good to me with my AT120E cart.
Great product.

Steve

Thanks Steve, we'll add it to the list!
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 27 Feb 2013, 02:42 am
I still listen to my original ACLE Phono-1 everyday, it is very good.
I am interested in trying the new opamps. Will you offer an upgrade service for original Phono1 owners?
Maybe a DIY upgrade kit?
Thanks Boris

Upgrade service is a very good idea. The PCBs are different. The original one will need to be replaced - that is fairly simple. But the op amps did not change. It is possible to install sockets that will make it easy to experiment with different op amps, although the selected ones are pretty hard to beat.

Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: WireNut on 27 Feb 2013, 03:19 am
 Moving my question to your Preamp/Cartridge Optimization thread. Sorry  :duh:

Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: SET Man on 27 Feb 2013, 04:39 am
Hey!

  Boris, that is one of the most flexible phono pre I've seen, gain and loading adjustable wise. I don't know any other at this price that can do that. Very nice. :D

Take care,
Buddy :thumb:
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: WireNut on 27 Feb 2013, 05:39 am
Hey!  Boris, that is one of the most flexible phono pre I've seen, gain and loading adjustable wise. I don't know any other at this price that can do that. Very nice. :D
Take care,
Buddy :thumb:

Yeah, I hear ya. My feelings exactly. Should I move up to the MK2 from the ACLE002 phono-1 Pre?
I have a lot of experimenting with cartridge's (as a newbe) in the future and I have NO idea what I'll end up with in the long run, so being able to adjust gain and loading seems like a BIG PLUS to me.

Thanks Mike, I'm enjoying the original ACLE Vista pre.  :thumb: 

Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: putz on 27 Feb 2013, 05:41 am
Upgrade service is a very good idea. The PCBs are different. The original one will need to be replaced - that is fairly simple. But the op amps did not change. It is possible to install sockets that will make it easy to experiment with different op amps, although the selected ones are pretty hard to beat.

+1 on the upgrade. How long to do? How much?

Would love to be able to use a better PS over the supplied wall wart, like the Pangea P-100

Love my Vista, Boris.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 27 Feb 2013, 12:11 pm
Hey!

  Boris, that is one of the most flexible phono pre I've seen, gain and loading adjustable wise. I don't know any other at this price that can do that. Very nice. :D

Take care,
Buddy :thumb:

Hi Buddy, long time no see! The preamp is indeed flexible (there is about 400 resistor values between 10 ohm and 100 kohm that can be selected for gain and loading - not that I provide all of them  :lol:)

But the user needs to do some work - remove cover and insert the resistor - not difficult, but not as simple to turning a switch. On the positive side, not having switches and extra wiring is a good thing, as far as I'm concerned. Good for sound and for wallet  :D
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 27 Feb 2013, 12:15 pm
Yeah, I hear ya. My feelings exactly. Should I move up to the MK2 from the ACLE002 phono-1 Pre?
I have a lot of experimenting with cartridge's (as a newbe) in the future and I have NO idea what I'll end up with in the long run, so being able to adjust gain and loading seems like a BIG PLUS to me.

Thanks Mike, I'm enjoying the original ACLE Vista pre.  :thumb:

Steve, the preamp you have is good for your AT120. No need to do anything just yet.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 27 Feb 2013, 12:27 pm
+1 on the upgrade. How long to do? How much?

Would love to be able to use a better PS over the supplied wall wart, like the Pangea P-100

Love my Vista, Boris.

Thaks - love to hear that you love the preamp!

Most of the cost is on the PCB, which needs to be replaced. We are probably looking at $180.

As for the power supply - the wall wart is only a transformer that I wanted to put outside the box. The rest is inside. If Pangea can output 12VAC than it can be used directly. I will take a look at other options for p/s upgrade.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 27 Feb 2013, 12:39 pm
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 28 Feb 2013, 01:42 am
Would it benefit a power supply upgrade?...

...Boris is gotta be doing it for the love of the hobby because he is sure not going to retire doing it.

Haha, I will never retire... luckilly, people pay me to do the other thing I also love - high frequency switching power supplies...

Better power supply would probably be beneficial (I would not expect dramatic changes, so this should be considered low priority), but it should be a DC supply that connects directly to the DC supply inside the unit (±15 to ±18V). I would need to figure out how to make that connection without too much mess.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 28 Feb 2013, 02:49 am
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 28 Feb 2013, 03:13 am
Thank you Den, glad you like it right out of the box!  I'm pretty happy that you like the settings I came up with. :D

Regarding the power supply: 12VAC made it possible to create internal supplies of +12V and -12V DC. Had I used 12VDC, the best I could get would have been +6V and -6V. Even though that would be sufficient most of the time, working with higher supply voltage allows for higher dynamic headroom and makes op amps operate further from the limit, which are both very good things.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 7 Mar 2013, 02:49 am
This really does look like an outstanding value.

What about capacitance loading, stick some silver micas in with the resistors?

Is there default capacitance on the board? 

Would 25 or 50pF be special order?

Is 0 shunt capacitance doable, or do you need some value there?

BTW, on your link those load resistors look like Dales.  I know it's Vishay/Dale, but Vishay has their own line which are commonly referred to as Vishay.  Just sayin.
neo
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 7 Mar 2013, 11:58 pm
Default capacitance is 150pF. Different capacitances are possible. I have many values in stock - if not in stock I'll need a few days to get them. Zero capacitance is also possible.

ACLE resistors are Vishay Dale, precision industrial

http://www.vishay.com/docs/31018/cmfind.pdf (http://www.vishay.com/docs/31018/cmfind.pdf)

Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 8 Mar 2013, 06:01 am
I think 150pF is a bit high for most modern MM carts.  AT recommends < 200pF total for all their MMs, and Ortofon is < 300.  Considering that internal arm wire + cables is usually 100 to 150pF.....

Good to know options and the versitility of your phono pre.  I wasn't schmoozing when I said it looks like an outstanding value.  In some ways it reminds me of my American Hybrid Technology, like the plug in resistors.  I'll probably be ordering one after I clear out some misc pieces.  I need another phono and I don't think anything else will come close except maybe for 4 or 5X the price. 

I know what Vishay-Dales are, I use some.  When Audiophiles read Vishay, they think this:
http://www.partsconnexion.com/prod_pdf/vishay_var.pdf

Regards,
neo
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 9 Mar 2013, 01:54 am
Thanks neo, you are very kind!

Yep, those are nice resistors, not sure if Vishay still makes them though. :(

I am finding that most modern MM cartridges work well with lower loading - 23k, or even 10k. With that loading capacitance is less critical. But it's not a problem changing it to lower value, Mica caps offer good bang for the buck.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: JackD on 9 Mar 2013, 01:58 am
Ordered mine today.  Boris and I are going to decide when he gets the parts in whether to do 20 or 50pf as the base value for capacitance.  Looking forward to experimenting with the loading on several cartridges I have that need something lower than 47kohm like the AT's and the DL-110.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 9 Mar 2013, 03:10 am
Thank you for the orders.   :)

Tracking information is in a separate thread, to make sure serial numbers are in order and contribution to AC is recorded.

http://www.audiocircle.com/index.php?topic=114482.msg1194610#msg1194610 (http://www.audiocircle.com/index.php?topic=114482.msg1194610#msg1194610)
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 9 Mar 2013, 03:25 pm
Boris,
Those naked resistors are the latest and greatest for audio, from Vishay.  They cost $16. ea retail for .1% (can get .01%) - not exactly cost effective, at least at this point.  Vishay makes encapsulated resistors for NASA - used to cost $60 ea, wholesale ('90s). The blue Dales are good clean sounding resistors, I think a good choice. I've used IRC RC55 series for loading - .1% so I don't have to match em. They seem neutral (Mouser around $1.20 ea). Even if you decide to build a state of art contender, you might want something a little sweeter like tantalum, if you're using ICs. There's a lot of prejudice against ICs, but they're superior to anything else in this application, assuming you want neutral, not euphonic.  Most designers don't know how to configure them for superior performance, and consequently some audiofools think they're only good for budget stuff.

I read the review on the thread below and some testimonials here.  Gives me a felling of deja vu. I'll have to get off my ass and snag one of these before you raise the price.  Don't know how you do it, you must have another source of income.
neo 
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 10 Mar 2013, 12:14 am
I agree about ICs. I was trained in electronics and can design with just about any electronic device out there, but ICs have some advantages that are very hard to beat:

1. Adding semiconductors costs nothing or very little. Designers are free to use best design practices (in biasing, current mirrors, and all the other good stuff) with very few limitations on circuit complexity. Not so when designing with discrete components.

2. Matched pairs, when required, come just about perfect (critical for low distortion). It is because they are all built at the same time, on the same substrate, just a few microns apart, where they share identical ambient conditions.

3. Cost keeps going down and quality goes up, something we should all love.

All this from someone who is still fascinated by how good things can be made with just a few simple parts... single ended triode amplifiers are a great example. But every component and design technique has its place and can give excellent results when implemented with skill and care.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 17 Mar 2013, 10:26 pm
nt


Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: JackD on 18 Mar 2013, 01:50 am
tomytoons

Mine will land middle of the week and I will look forward to see how it sounds.  First up is the Denon Dl-110 at a lower resistance and then the Grado's.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 18 Mar 2013, 03:23 am
Hey JackD,
What impedance do you like for the 110?  I used to have a 160 and I liked 9K.  Some other people used 1K. I'm not as familiar with the 110, but it seemed pretty good at 47K.
neo
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: bacobits1 on 18 Mar 2013, 10:04 am
I was thinking about getting a DL110too just stash it. Supposed to be real in cartridge for cheap.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: rollo on 18 Mar 2013, 02:54 pm
  I have been playing around with the MK2 using a Linn Arkiv at .15mv loaded at 100 ohms. So far no slouch. Very surprised actually with its performance.  Clean, dead quite, detailed enough and engaging.
   To keep it simple in all my 40 years in this game never has a product offered so much KA_BOOM for the buck. period end of story. Compared to my State of the Art phono [ Loesch & weisner ] it was  matter of omission in direct comparison. The Vista does no harm. The bass is outstanding and more powerfull than my reference. Buy one ! Not a dealer for Vista.


charles
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: JackD on 18 Mar 2013, 10:35 pm
neobop

I have only tried the DL-110 so far at 47kohm and then briefly at 36kohm as I had a set of loading plugs around that I used to take the 100kohm setting on the preamp down to 62kohm to experiment and see if like Felix from AK said it made a difference with the M97xe.  And while the Denon may have been somewhat better at 36 than 47 I didn't stay with it long before I went back to the 8MZ.  In addition to the extra resistors that come with the Phono-1, I have ordered about 10 other values of the Vishay CMF55's Boris recommended  to have other options too.

Jack
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 18 Mar 2013, 10:54 pm
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: JackD on 18 Mar 2013, 11:39 pm
Ordered them from Mouser, but I think Boris uses Digikey.  They seem to be within pennies of each other price wise.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 19 Mar 2013, 01:29 am
  I have been playing around with the MK2 using a Linn Arkiv at .15mv loaded at 100 ohms. So far no slouch. Very surprised actually with its performance.  Clean, dead quite, detailed enough and engaging.
   To keep it simple in all my 40 years in this game never has a product offered so much KA_BOOM for the buck. period end of story. Compared to my State of the Art phono [ Loesch & weisner ] it was  matter of omission in direct comparison. The Vista does no harm. The bass is outstanding and more powerfull than my reference. Buy one ! Not a dealer for Vista.


charles

Thank you Charles! Linn is a very challenging cartridge, I am very glad that Phono-1 is handling it well. We can try slightly higher loading, see if that makes any difference.

Thanks again,
Boris
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 19 Mar 2013, 01:30 am
JackD's preamp is on it's way!
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 25 Mar 2013, 12:59 pm
nt


Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 26 Mar 2013, 12:15 am
Somebody is having fun!  Way to go Den :thumb:
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: JackD on 26 Mar 2013, 12:33 am
tomytoons

Got my order in today from Mouser so I now have plenty of options with it and what Boris included.  Been thinking about trying a LOMC for the first time and the two you are dealing with are at the top of the list.  Would be interested in hearing your opinions on the two of them.  Going to start my experiments with loading tomorrow.  For now I have just left the unit like it was delivered at 40db, 47Kohm and 50pf.  Sounds fine with both the Grado Z1+/8MZ and the Denon DL-110 but I am sure fine tuning will make it better.  Like others have said this thing sounds way above it's price range and is a steal.

Jack
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 27 Mar 2013, 01:33 pm
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 12 Apr 2013, 01:06 pm
nt

Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: JackD on 12 Apr 2013, 01:46 pm
For my unit 50pf is the default.  Boris's standard default is 150pf.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 12 Apr 2013, 04:16 pm
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 17 Apr 2013, 06:03 pm
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 17 Apr 2013, 08:06 pm
I will post this since I'm a dum di dum dum and may help others as far as anything on this loading stuff.
Through the generous help of JackD this site will calculate any given resistance values you may need.
Very useful. Hey, I'm a dip switch person.  :roll:

http://www.electronics2000.co.uk/calc/series-parallel-resistor-calculator.php

Use the Resistors in Parallel calculator.

Thanks Jack for all the answers and time to my questions.

Is 50pf the default Capacitance?

I didn't realize the plug in load resistors are in parallel with 47K.  That means that 47K can not be exceeded, you can only load down.   There are a few carts that do much better at loads greater than 47K.  The Shure M97 comes to mind, many people prefer 62 to 70K.   A nice solution to this would be to order 1 Mohm as the default.  Then any plug in resistor would have it's value as the load. 

Most modern MM carts want to see < 200 or 300pF total capacitance.  Maybe if you order a 50pF default, another cap could be added to the load resistor if needed?  Arm wire + cables are usually 75 to 150pF.   Sometimes 300pF or so is used for LOMC.  There are a few LOMC that have a lot of inductance for their output and can cause ultrasonic ringing or oscillation in some preamps with extended bandwidth.  This can cause intermodulation distortion.  Maybe 300pF would prevent that?  Not sure about that, but I think those caps are for noise.

BTW, many carts that are perceived too bright like the AT-440, are often run at 32K.  That's 47K in parallel with 100K.  Any lower and it's too dull on most preamps.
neo

Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 17 Apr 2013, 08:28 pm
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 18 Apr 2013, 01:51 am
Thanks for sharing your experiences guys!

Changing default input resistors and capacitors would not be a problem. I can install pretty much any value. There would be no charge for that.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 18 Apr 2013, 11:03 am
Just how much better are these?
$$$$$
http://www.partsconnexion.com/resistors_vishay_var.html

In an ultimate sense they're better, but I don't think they make much sense in this application.  I can hear a slight difference in my AHT where there are no other resistors in parallel, but sometimes I use the same Dale resistors and they sound just fine.  The advantage for me is mainly in temperature stability with some of the more expensive resistors, because there is no auto DC offset circuit and it drifts with temperature.  Setting the DC offset is a PIA and takes some time.  That's one of the reasons I plan on getting the Vista.  It's plug n play in comparison and I think I already know how it sounds - fast, clean, and neutral.  I want to hear what's on the record, not some romanticised version of what's there.  I have some other phono stages built into preamps or integrated amps, but I doubt if they come close to Vista.
neo

I almost forgot, you can call Mouser or Digikey on the phone to order resistors.  If you know the brand(s), values and tolerance you want, it's a lot easier.  I know Mouser has IRC R55 .1% metal film, and Dale PTF series .1% Ultra High Stability.  Can't go wrong with either of these and you don't have to match em.  Whoever helps you on the phone can see in an instant if they're in stock etc. 
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 18 Apr 2013, 11:45 am
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 18 Apr 2013, 01:29 pm
Are some of the ultra expensive Phono Pre's using resistors like those?
I bet not.
If you are building your own boards as Nick77 is, I would think about it. It is a dual mono design with a Gary Dodd custom power supply. He has got it done maybe he will share his experience with it in the vinyl section. I sure would like to hear it.

I do not think it necessary going that high $ in the Vista.
It is "fast, clean, and neutral" I'm going to leave well enough alone.
I have a mass amount of choices here now.
 
Still, you think what if..........

I think a couple of them are using nude Vishays.  Some high end units have sealed modules so you can't see what's inside.  This is done mostly to keep other companies from stealing the design, really.  A patent that's worth anything costs big bucks and other companies will steal it anyway and fight it in court yrs later.  The consumer electronics industry is ruthless in that respect, as is most big business.  So an ounce of prevention...   I think this started with Mitch Cotter in the '70s.  He used to seal all his electronics in what looked like expanding foam.  I had a Cotter SUT that had little silver jumpers in the side of the unit.  You could resolder the little jumpers to configure it for different gain and impedance.  It had captive silver cables coming out, and the inside was completely sealed. 

The AHT Non Signature phono stage was the only 5 star component in TAS for something like 3 yrs running in the late '90s.  The TOTL sold direct for around $5K, not really expensive by today's standards, but if it went through dealers it would have been close to $10K.   You could see where the money went though, it had teflon boards with silver traces.  A couple of caps on each channel were teflon and the plug in resistors for load and gain were the encapsulated Vishay they used in the space shuttle.  The regular version of the IC, 3 per ch, cost $30 ea today, but the military version was used, at least for the one handling the signal.  The power supply had a hugh toroidal transformer which could power a pretty big amp.  My AHT isn't the TOTL, but I have the teflon boards and caps and a big power supply with regular Vishay 102, I think they are.  Those are the ones I substitute sometimes.  When the AHT designer got out of the audio biz, he had offers from Herron and Walker to buy the design.  He sold it to Walker and it now has a DC offset circuit and sells for $14K. 

I have no idea what Nick77 is building, and I don't really know how much difference a nude Vishay or a space shuttle resistor would make.  They are super stable in all kinds of temp, if the music puts you in space.   :roll:

My suggestion would be to save the money and get more records.
neo
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 18 Apr 2013, 01:46 pm
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 27 Apr 2013, 08:32 pm
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: topround on 27 Apr 2013, 09:01 pm
I had the oc9 for some time and I thoroughly enjoyed it. Very musical, gives a taste of what great MC's can do for a fraction of the price.  Play with different stepups it will be fun with that cart.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: cheap-Jack on 27 Apr 2013, 09:23 pm
Hi.
.
.. There are a few carts that do much better at loads greater than 47K.  The Shure M97 comes to mind, many people prefer 62 to 70K.   A nice solution to this would be to order 1 Mohm as the default.  Then any plug in resistor would have it's value as the load. 


"Much better" at what? Higher than 47K load will sound better or what?

With my DIY tube phonostage, I used a 100KR trimmer as my MM cartridge load. I found trimming up & down across 47KR mean value, the entire frequency response lever is somewhat lifted towards LF or HF.
In my case, I found setting it to 52KR, the bass is somewhat boosted up a couple dBs & is fairly noticeable.

c-J

Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 29 Apr 2013, 02:31 pm
Hi.
"Much better" at what? Higher than 47K load will sound better or what?

With my DIY tube phonostage, I used a 100KR trimmer as my MM cartridge load. I found trimming up & down across 47KR mean value, the entire frequency response lever is somewhat lifted towards LF or HF.
In my case, I found setting it to 52KR, the bass is somewhat boosted up a couple dBs & is fairly noticeable.
c-J

Loading is relevent only for a specific cartridge.  In general, a dull or rolled off cart will sound flatter using a higher resistance value and the opposite is true for an overly bright cart.

http://www.tnt-audio.com/sorgenti/load_the_magnets_e.html

Many people load the M97 at 62K while others load the AT-440MLa at 32K.  To a large extent it depends on the sound of your system, and taste. 
neo
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 4 Jun 2013, 11:00 pm
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: jimdgoulding on 19 Jun 2013, 10:53 pm
Boris, please reply to me when you are able at jimdgoulding@yahoo.com.  I wish to purchase and don't seem to be able to negotiate the links at your site.  Thanks, Jim. 
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Audiovista on 25 Jun 2013, 01:05 am
Boris, please reply to me when you are able at jimdgoulding@yahoo.com.  I wish to purchase and don't seem to be able to negotiate the links at your site.  Thanks, Jim.

I am finally back home! Jim - thank you for the order.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: jtwrace on 25 Jun 2013, 01:10 am
Look forward to the feedback Jim.  What do you have now?
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 25 Jun 2013, 11:59 am
Haha, I will never retire... luckilly, people pay me to do the other thing I also love - high frequency switching power supplies...

Better power supply would probably be beneficial (I would not expect dramatic changes, so this should be considered low priority), but it should be a DC supply that connects directly to the DC supply inside the unit (±15 to ±18V). I would need to figure out how to make that connection without too much mess.

I was wondering if you made any progress on that power supply connection.  Wasn't that top priority while you were on vacation?   :wink:

Did you ever spec the S/N on the Phono-1 MkII?  I didn't see it on the web site.  I guess it would vary with gain.
neo
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Airborn on 1 Jul 2013, 09:28 am
I'm interested in the Vista MkII ACLE, but am wondering about the different loading options for my MM carts because I have quite a few budget MM, including a Shure M97xe, Denon DL-110, AT 440-MLa and AT 150-MLx.  Should I get the Vista preset for my preferred cart (the AT 150MLx) or is there a setting that would be good for all these carts?  Am I going to have to change input resistors and capacitors every time I want to use my other cartridges?
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: jimdgoulding on 1 Jul 2013, 09:46 am
Look forward to the feedback Jim.  What do you have now?
A Monolithic Sound phono pre.  My new Shelter 501II MC cartridge is breaking in with it now so I should be better able to compare when the Vista gets here in a week or so.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: jtwrace on 1 Jul 2013, 11:23 am
A Monolithic Sound phono pre.  My new Shelter 501II MC cartridge is breaking in with it now so I should be better able to compare when the Vista gets here in a week or so.
Cool
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: jtwrace on 1 Jul 2013, 11:24 am
I'm interested in the Vista MkII ACLE, but am wondering about the different loading options for my MM carts because I have quite a few budget MM, including a Shure M97xe, Denon DL-110, AT 440-MLa and AT 150-MLx.  Should I get the Vista preset for my preferred cart (the AT 150MLx) or is there a setting that would be good for all these carts?  Am I going to have to change input resistors and capacitors every time I want to use my other cartridges?
If the settings are all different then yes, you will need to change resistors as required.  OR, you can buy 3 Phono-1 MKII's and have a dedicated one for each.   :wink:
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 1 Jul 2013, 12:32 pm
nt

Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 1 Jul 2013, 12:49 pm
I'm interested in the Vista MkII ACLE, but am wondering about the different loading options for my MM carts because I have quite a few budget MM, including a Shure M97xe, Denon DL-110, AT 440-MLa and AT 150-MLx.  Should I get the Vista preset for my preferred cart (the AT 150MLx) or is there a setting that would be good for all these carts?  Am I going to have to change input resistors and capacitors every time I want to use my other cartridges?

IMO you should get a custom configuration for resistance and an auxiliary set of capacitors.  A stock M97 is flatter at 62Kohm/250pF total capacitance.

The 150MLX is usually loaded 42 to 47K, but capacitance should be < 200pF.  Capacitance includes internal arm wire + cables + preamp. 

DL-110 is somewhere between 1K and 47K.  Capacitance shouldn't matter.

You can order it so that the value of your plug-in resistors is the final value.  62K for the M97 is taken from many users preference.  It fills in some drooping treble, but 250pF should be maintained.  Depending on your table, capacitance varies usually between 75 and 150pF.  So 50pF default for the AT and an additional 100pF for the Shure?
neo
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: Airborn on 1 Jul 2013, 11:38 pm
Thanks for the replies.  Tomytoons, I know I said I have all MM, but I realize the DL-110 is HOMC.  It's just that I use it on the MM setting with my Cambridge 640P b/c the output is so high, so I usually don't think of it as a MC.  I have a Technics 1210 M5G with the upgraded tone arm wiring, so I think neo is correct that I should get a lower default capacitance of 50pf or so for use with my preferred cart, the AT 150 MLx.  Then I can plug in resistors to get the correct loading if I want to change carts.  I guess I should call Boris and see what he recommends. :duh:
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 2 Jul 2013, 12:21 am
nt
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: MaxCast on 2 Jul 2013, 10:46 am
Can anyone that has one of these take a pic as to what is actually required to change a resistor?
Do they actually plug in?
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: jtwrace on 2 Jul 2013, 11:07 am
Can anyone that has one of these take a pic as to what is actually required to change a resistor?
Do they actually plug in?

http://vista-audio.com/products/phono-1mkII/settings.htm

and for more technical reading: http://vista-audio.com/products/phono-1mkII/why_optimize.htm
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: neobop on 2 Jul 2013, 11:15 am
Unlike parallel resistors, the final value of which must be calculated, capacitor values in parallel are additive.  If the minimal value to be used is ordered for default (in this case 50pF?),  then using an additional 100pF would yield a total value of 150pF.  This is assuming 100pF for the internal arm wire and cables. 

I'm not sure about the physical location of additional capacitors, maybe they can be attached to load resistors.  Resistors are inexpensive and in this case 100pF caps could be soldered on to a set of 62K resistors for a final value of 62K + 150pF.  Otherwise, maybe they could be stuffed into the sockets along with the resistors.

I'm afraid that modifications we're asking for, including my power supply question, might of necessity drive up the price of Vista Phono 1 MKII, if implemented.  After thinking about it, these considerations aren't a deal breaker for me and maybe I'll get my order in sooner rather than later.  I have an old 24V DC supply from a Sota Sapphire that I could use, but it might not even be the correct voltage for DC.  12V AC might be a challenge to upgrade, but I'm not sure it needs it.
neo

 

 
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: MaxCast on 2 Jul 2013, 01:35 pm
http://vista-audio.com/products/phono-1mkII/settings.htm

and for more technical reading: http://vista-audio.com/products/phono-1mkII/why_optimize.htm
:duh: Thank you.
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: JackD on 2 Jul 2013, 02:19 pm
MaxCast

Changing the resistors is easy.  I have probably done it over a dozen times.  Just need a steady hand and either tweezers or small needle nose pliers.  If you have a larger electronics parts supplier in you area you can buy the resistors for about $1.50 a pair and tweek to any value below 47k you want.  As to the capacitance, I had both of mine set to 50pf. You can always add.  The capacitors though cannot be stuffed into the sockets with the resistors.  If you had the rare cartridge, mostly from the 70's, that need higher capacitance, then to me loading plugs are an easier solution.  As a rule MC's and the Grado's are not capacitance sensitive unless you go crazy.


Jack
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: MaxCast on 2 Jul 2013, 05:22 pm
Thank you for that.  To remove you grip with small needle nose and pull out?
Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: tomytoons on 2 Jul 2013, 05:43 pm
I highly recommend the Vista and will continue to.
Some people look at you skeptical and stupid make accusations because you enthusiastically recommend something.
In that case it is their loss.

When I deleted my posts here I was ripped at someone else on another board but these people are on all boards.
So I will just keep things to myself from here on in. Yes, I get "thin skinned" at times.

Title: Re: Phono-1 MkII - AudioCircle Limited Edition
Post by: JackD on 2 Jul 2013, 06:26 pm
Rich

You can actually just pull them out buy hand.  I only use the tools to put them in.  Another thing, Boris intentionally leaves the legs on the resistors a little long to make it easier to get them in and out.  This does however make them a little top heavy and easier for them to become dislodged.  Once you get used to it you might want to shorten them a bit to lower the center of gravity. 

Jack