Phono-1 MkII - AudioCircle Limited Edition

0 Members and 1 Guest are viewing this topic. Read 66365 times.

Audiovista

Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #20 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.

tomytoons

  • Jr. Member
  • Posts: 286
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #21 on: 28 Feb 2013, 02:49 am »
nt
« Last Edit: 3 Jul 2013, 02:16 pm by tomytoons »

Audiovista

Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #22 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.

neobop

  • Full Member
  • Posts: 3448
  • BIRD LIVES
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #23 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

Audiovista

Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #24 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


neobop

  • Full Member
  • Posts: 3448
  • BIRD LIVES
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #25 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

Audiovista

Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #26 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.

JackD

  • Full Member
  • Posts: 1397
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #27 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.

Audiovista

Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #28 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

neobop

  • Full Member
  • Posts: 3448
  • BIRD LIVES
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #29 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 

Audiovista

Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #30 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.

tomytoons

  • Jr. Member
  • Posts: 286
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #31 on: 17 Mar 2013, 10:26 pm »
nt


« Last Edit: 3 Jul 2013, 02:16 pm by tomytoons »

JackD

  • Full Member
  • Posts: 1397
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #32 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.

neobop

  • Full Member
  • Posts: 3448
  • BIRD LIVES
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #33 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

bacobits1

Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #34 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.

rollo

  • Industry Participant
  • Posts: 5439
  • Rollo Audio Consulting -
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #35 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

JackD

  • Full Member
  • Posts: 1397
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #36 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

tomytoons

  • Jr. Member
  • Posts: 286
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #37 on: 18 Mar 2013, 10:54 pm »
nt
« Last Edit: 3 Jul 2013, 02:17 pm by tomytoons »

JackD

  • Full Member
  • Posts: 1397
Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #38 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.

Audiovista

Re: Phono-1 MkII - AudioCircle Limited Edition
« Reply #39 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