• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

The Official "Build" thread for the V4 WYN Phono preamplifier

wyn palmer said:
The board has what I thought were clear instructions printed on it for wiring up the power and mute switches.
Have you attempted to follow them? If so, what was confusing about the instructions? If not- why not?
Click to expand...
I see it now. Thanks
 
Would someone please direct me to the right person to purchase the circuit boards from? I would like to try my hand at building one.
 
The first post has the gerbers. There is no group buy so you need to order the boards unless someone has an extra they will sell.
 
I used to sell boards, but the tax changes made it ill advised. The tax situation has changed with the new administration, but I don't see the demand.
 
Moderator note: all sales, even free exchange of parts or such, is only allowed by AK rules in the Bartertown forums.
 
@mkane generously loaned me his V4 so I could hear it in my system. My comparison is with my dual opamp versions of the V2 MM and MC. I used my Dynavector TKR MC cart with V4 MC (60Ω loading) and V4 MM combined with Intact Audio's 1:20CU SUTs (25Ω loading at SUT) and then with my Nagaoka MP-500 MI with the V4 MM at both 47kΩ and 100kΩ loading. I don't do the eloquent audiophile speak well and even though audio memory is notoriously short I don't have any doubt that the V4 sounds better in my system than the V2 MM and MC. Regardless of the cartridge or whether the V4 was in MM, MC or MC/SUT the sound via the V4 was clearer than the V2. "A veil was lifted off my vinyl playback" in audiophile jargon I suppose. I am certainly aware that volume can influence the impression of sound quality but I used a SPL meter to get the volume as close as possible to my normal listening level plus at lower volumes I had the same impression: the V4 delivers excellent clarity.

The V4 was in a chain of gear (listed in my signature below) and with the V4 my system was really quiet. I had to get my ear a couple of inches away from my speaker's mid-range to hear any hiss/noise. In between songs or the lead-in grooves the background was quiet too. However, I played a couple of records that apparently need to be run through the US cleaner as I could more easily hear the random clicks and pops. Apparently, clarity does not apply to just the music but whatever the stylus encounters.

I like the range of loadings provided by the six resistors on the DIP switch and the fixed 100kΩ. I have @wyn palmer 's spreadsheet to calculate the loading if other resistor values are used and I may change the values since the Nagaoka MP-500 sounds really good at about 57kΩ. I need to look at the schematic to see if I could add a RCA jack that attaches to the PCB that would allow custom resistor values for cartridges (taking into account the 100kΩ is always there) that need odd loading.

I hope to be upgrading to the V4 in the near future.
 
mkane said:
Its quieter than v3.2 also. I’ll send you one of those to compare you wish.
Click to expand...

A generous offer but if V4 is quieter than 3.2, well, I'm good. :) I'm going to have a hard time boxing this up to send back to you! Linda Ronstadt Heart Like a Wheel, MOFI is spinning on my SP-25/Nag MP-500 and good gracious!
 
AvFan said:
@mkane generously loaned me his V4 so I could hear it in my system. My comparison is with my dual opamp versions of the V2 MM and MC. I used my Dynavector TKR MC cart with V4 MC (60Ω loading) and V4 MM combined with Intact Audio's 1:20CU SUTs (25Ω loading at SUT) and then with my Nagaoka MP-500 MI with the V4 MM at both 47kΩ and 100kΩ loading. I don't do the eloquent audiophile speak well and even though audio memory is notoriously short I don't have any doubt that the V4 sounds better in my system than the V2 MM and MC. Regardless of the cartridge or whether the V4 was in MM, MC or MC/SUT the sound via the V4 was clearer than the V2. "A veil was lifted off my vinyl playback" in audiophile jargon I suppose. I am certainly aware that volume can influence the impression of sound quality but I used a SPL meter to get the volume as close as possible to my normal listening level plus at lower volumes I had the same impression: the V4 delivers excellent clarity.

The V4 was in a chain of gear (listed in my signature below) and with the V4 my system was really quiet. I had to get my ear a couple of inches away from my speaker's mid-range to hear any hiss/noise. In between songs or the lead-in grooves the background was quiet too. However, I played a couple of records that apparently need to be run through the US cleaner as I could more easily hear the random clicks and pops. Apparently, clarity does not apply to just the music but whatever the stylus encounters.

I like the range of loadings provided by the six resistors on the DIP switch and the fixed 100kΩ. I have @wyn palmer 's spreadsheet to calculate the loading if other resistor values are used and I may change the values since the Nagaoka MP-500 sounds really good at about 57kΩ. I need to look at the schematic to see if I could add a RCA jack that attaches to the PCB that would allow custom resistor values for cartridges (taking into account the 100kΩ is always there) that need odd loading.

I hope to be upgrading to the V4 in the near future.
Click to expand...
Yes, you can add an external resistor in parallel with the 100k input to produce the desired load. Just don't do anything internal to the circuit after the input coupling cap. That would be bad as it will affect the settling/range of the input buffer bias loop with potentially catastrophic consequences.
 
wyn palmer said:
Yes, you can add an external resistor in parallel with the 100k input to produce the desired load. Just don't do anything internal to the circuit after the input coupling cap. That would be bad as it will affect the settling/range of the input buffer bias loop with potentially catastrophic consequences.
Click to expand...

Thanks Wyn. Good to know I can keep the six load resistors and add a load jack position to the 100kΩ. Also, I modified your loading spreadsheet by zeroing the sixth resistor position (Pin 8) and found that 5 positions also provided an excellent variety of typical MC loads. I could attach the load jack to Pin 8 to make sure it is in correct spot within the circuit. The external load jack/plug will allow loads for some MM/MI carts like my Grado (10kΩ), some Shures (65kΩ) and a Nagaoka I own that is best at about 60kΩ.

Just to be sure: 1) If I leave the Pin8 position without a resistor will it adversely affect the circuit? 2) If I fill Pin 8 with a resistor from a load plug and leave all other Pins OFF will that adversely affect the circuit? Thanks!
 
AvFan said:
Thanks Wyn. Good to know I can keep the six load resistors and add a load jack position to the 100kΩ. Also, I modified your loading spreadsheet by zeroing the sixth resistor position (Pin 8) and found that 5 positions also provided an excellent variety of typical MC loads. I could attach the load jack to Pin 8 to make sure it is in correct spot within the circuit. The external load jack/plug will allow loads for some MM/MI carts like my Grado (10kΩ), some Shures (65kΩ) and a Nagaoka I own that is best at about 60kΩ.

Just to be sure: 1) If I leave the Pin8 position without a resistor will it adversely affect the circuit? 2) If I fill Pin 8 with a resistor from a load plug and leave all other Pins OFF will that adversely affect the circuit? Thanks!
Click to expand...
The value of the resistance in any of the load positions is largely irrelevant, and the loops are stable even with all the Rs open or closed. The MM setting is more sensitive as the closed loop gain is lower, but I don't think that any of the values you propose in position 8 will have any noticeable consequence.
 
wyn palmer said:
The value of the resistance in any of the load positions is largely irrelevant, and the loops are stable even with all the Rs open or closed. The MM setting is more sensitive as the closed loop gain is lower, but I don't think that any of the values you propose in position 8 will have any noticeable consequence.
Click to expand...
Thanks! Below is my attempt to figure out the load plug value for a variety of possible loads with the 100kΩ resistor in the circuit. Below about 500Ω the plug value is essentially equal to the target load but those values start to diverge around 500Ω to maybe 3000Ω. If the DIP switch is hard to reach for some reason or someone wants to change loads frequently then using just the load plug might be handy. Hopefully this chart is correct.

V4 Load Plug with 100kohm jpg.jpg
 
AvFan said:
Thanks! Below is my attempt to figure out the load plug value for a variety of possible loads with the 100kΩ resistor in the circuit. Below about 500Ω the plug value is essentially equal to the target load but those values start to diverge around 500Ω to maybe 3000Ω. If the DIP switch is hard to reach for some reason or someone wants to change loads frequently then using just the load plug might be handy. Hopefully this chart is correct.

View attachment 3660924
Click to expand...
It looks fine to me, having looked at a few results.
 
The v4 has been out in the wild for a bit now. The consensus seems to be that it is better than the v3.2 and significantly better than the stripped-down commercial version of the
v3- the Pyxi.

A comment from one listener. comparing the Pyxi and the V4

This is a different animal. Much deeper sound stage. More expansiveness. I’m pretty blown away so far.

​
If I get further comments I will post them.
Bill Hirsch has suggested making a remote-controlled version of the "cheapphono" by adding a couple of additional front and rear panel boards to replace the mechanical switches with relays.
We are considering this. Such boards could use some of the pre-built microcontrollers/IR receivers that are available cheaply from China and could ease the DIY construction issues.
 
I'm not sure I would have a lot of need for a remote controlled phono stage but I think it is great that you guys are continuing to explore options.
Keep up the good work
best
 
You must log in or register to reply here.
Back
Top Bottom