LIO MM/MC Phono Stage

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TomS

LIO MM/MC Phono Stage
« on: 23 Jan 2015, 04:33 pm »
Vinnie,

Can you please explain how the 2 loading options for the phono stage work for MC? I have a Soundsmith Hyperion 2 with output that is MC level but loads best somewhere between 1-2k.

- The standard MM/MC module states for MC "16 load settings from 26 to 400 Ohms".
  What are the 16 steps?

- With the optional Remote Cartridge Loading (RCL) module it states
    "255 individual settings for high precision cartridge loading" and
    "Load Range from 5 to 5000 Ohms"

   - Does this sort of "override" the standard 26-400 or is there a dependency?
     I remember talking to you about it at RMAF but can't recall exactly how it works.
   
   - Are the 255 settings at a fixed interval or a pattern?
   
   - Could you post a spreadsheet of the 255 settings on your site somewhere?

Thanks!

Tom

Vinnie R.

Re: LIO MM/MC Phono Stage
« Reply #1 on: 23 Jan 2015, 10:32 pm »
Vinnie,

Can you please explain how the 2 loading options for the phono stage work for MC? I have a Soundsmith Hyperion 2 with output that is MC level but loads best somewhere between 1-2k.

- The standard MM/MC module states for MC "16 load settings from 26 to 400 Ohms".
  What are the 16 steps?

- With the optional Remote Cartridge Loading (RCL) module it states
    "255 individual settings for high precision cartridge loading" and
    "Load Range from 5 to 5000 Ohms"

   - Does this sort of "override" the standard 26-400 or is there a dependency?
     I remember talking to you about it at RMAF but can't recall exactly how it works.
   
   - Are the 255 settings at a fixed interval or a pattern?
   
   - Could you post a spreadsheet of the 255 settings on your site somewhere?

Thanks!

Tom

Hi Tom,

With MC, the max load will actually end up being 2K. 

John (Bent Audio) and I have made some changes before finalizing the PCB, and that was one of them!  8)

So no matter if you are using only the LIO Phonostage (via the DIP switches to set the MC load), or the LIO Phonostage with
the RCL (remote cartridge loading) board to set the load, the highest load setting will be 2k for the MC.

- With just the LIO Phonostage, there will be 16 different load settings via the DIP switches.
- With the LIO Phonostage + RCL module, there will be 255 load settings, and this can be done on the fly as you listen... via
the front panel or remote.

[When the RCL module is used, you won't be using the DIP switches to set the load].

Yes - I will be posting the load values for both soon.  If you are using RCL, then the front panel will also display the load setting
in ohms when you are in the "LOAD' mode, so you will know what you are set to.

And speaking of the LIO Phonostage, we are now using step-up transformers for the MC input.  The step-ups add 20dB on top of the ~ 40dB of the MM JFET stage.  A cylindrical mu metal cover goes around the step-ups.  They are mounted onto the LIO Phonostage board.  Initially I was going to use a JFET stage for the 20dB gain at the MC input as well, but after trying the step-ups, there was no comparison!  The step-ups not only had much lower noise, but the sound has more punch, more air, more delicacy... it is "tasty!" :drool:

More details and pics of the phonostage are coming soon enough...

Vinnie

jtwrace

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Re: LIO MM/MC Phono Stage
« Reply #2 on: 24 Jan 2015, 12:57 am »
Vinnie & Alexis = Badass.   8)

TomS

Re: LIO MM/MC Phono Stage
« Reply #3 on: 24 Jan 2015, 02:33 am »
Thanks Vinnie! Sounds like a great plan to me and looking forward to the details.

trev4h

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Re: LIO MM/MC Phono Stage
« Reply #4 on: 3 Feb 2015, 09:14 pm »
And speaking of the LIO Phonostage, we are now using step-up transformers for the MC input.  The step-ups add 20dB


Vinnie - that will make the SUT ~ 1:10.  That is too low a ratio for my phono cartridge - Any chance we can specify the parameters of the SUT used in our phono module?  That is something that would be very valuable.   


Vinnie R.

Re: LIO MM/MC Phono Stage
« Reply #5 on: 3 Feb 2015, 10:09 pm »
And speaking of the LIO Phonostage, we are now using step-up transformers for the MC input.  The step-ups add 20dB


Vinnie - that will make the SUT ~ 1:10.  That is too low a ratio for my phono cartridge - Any chance we can specify the parameters of the SUT used in our phono module?  That is something that would be very valuable.

Hi trev4h,

Welcome to the VR forum!

Actually, John Chapman and I designed the LIO Phono board to also accept the CineMag transformer footprint (PCB mount).  I believe CM-1254. 

They offer 1:10, 20, and 40.  So YES, if you need more gain, we can custom order the 26dB or 32dB versions.  Bam! Wink2

Just email me to discuss details and we can go from there.

Vinnie

trev4h

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Re: LIO MM/MC Phono Stage
« Reply #6 on: 4 Feb 2015, 04:15 am »
Brilliant!

CarterB

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Re: LIO MM/MC Phono Stage
« Reply #7 on: 8 Mar 2015, 07:21 pm »
For the MM input, what is the capacitance?

Vinnie R.

Re: LIO MM/MC Phono Stage
« Reply #8 on: 9 Mar 2015, 02:35 am »
For the MM input, what is the capacitance?

Hi CarterB,

None is added on the board, so it is primarily be dominated by the cable that you use.  However, it you require a particular value, we can easily match and install caps across the input jacks of the module. 

In almost all cases it really isn't needed because the cable capacitance between the phono cartridge headshell and the LIO phonostage input will be sufficient / more than sufficient.  Most cartridges perform their best with the lowest possible capacitance, and adding more would not make things better - along with the fact that few people have the equipment to accurately measure the capacitance of their interconnects or the internal tone arm cables (typically around 100pF) to factor this into the total capacitance that the cartridge sees.

Vinnie

TomS

Re: LIO MM/MC Phono Stage
« Reply #9 on: 7 May 2015, 07:22 pm »
Just as a follow up to this thread, I determined that the stock gain of ~60db wasn't quite enough for my Soundsmith Hyperion cartridge. It is a great testament to the modular design to note that I popped the phono module out in less than a minute, boxed it up, and shipped just the module back to Vinnie. He had it right back to me inside of the same week round trip, with a slight mod to the JFET stage for 6-7db more gain, and it sounds terrific so far, plenty of gain.

This was great service, especially right after a busy show in Chicago, and yet another reason why I love what these folks have come up with  :thumb:

Vinnie R.

Re: LIO MM/MC Phono Stage
« Reply #10 on: 12 May 2015, 04:33 pm »
Just as a follow up to this thread, I determined that the stock gain of ~60db wasn't quite enough for my Soundsmith Hyperion cartridge. It is a great testament to the modular design to note that I popped the phono module out in less than a minute, boxed it up, and shipped just the module back to Vinnie. He had it right back to me inside of the same week round trip, with a slight mod to the JFET stage for 6-7db more gain, and it sounds terrific so far, plenty of gain.

This was great service, especially right after a busy show in Chicago, and yet another reason why I love what these folks have come up with  :thumb:

Hi TomS,

Glad that added gain did the trick!  :wink:

Thanks for your post and proving how simple the process  was - that is EXACTLY what I had in mind!  :idea:

Enjoy it!

Vinnie