Mike,
Comparing the phono section in the WV has turned into a far more involved process than comparing the line stage. With variables such as loading, gain and noise level, it takes time to find an optimum setting for a cartridge. The Aria's MM stage uses a pair of 6922 tubes for a gain of approximately 35db. This simplistic circuit with the two tubes brings on a level of clarity I have not heard before with phono.
I have not had the opportunity to audition other phono stages. I have wanted to try the Lamm LP2, ARC PH7 and Einstein but I have not been able to locate these. I have once again compared the Aestheix Io signature which has been a long time favorite because of its incredible midrange texture and bloom. And the Io's gain when used with ultra low noise tubes on the input stage allows for use of low output MCs.
For both the Koetsu RWS and Clearaudio Accurate, I found the "best" loading with the Aestheix Io to be 500 ohms. Into the WV's Sowter stepup transformer input, there was not much of a difference between 200, 300, 500 ohms. I tend to run at 200/300 ohms now which mates well with the 7062 tubes in the WV line stage being just a wee bit hot in the trebles.
Solid state phono stages have many attributes that appeal to me, but I just don't like the end result of a solid state input for the first gain stage on even an otherwise all-tube design. Years ago I tried the Klyne and this was very resolving and ultra-low noise but it was just too sterile for me. And the same with the Spectral. So I have stayed with tube based phono stages (other than the ARC PH2 10 years ago) noise and all because of the " musicality" even though the noise level was higher. Perhaps modern solid state designs have improved in this respect.
Another direction I have taken has been to play with external MC stepup devices.....the classic tube products from the 1980s. These can be used directly into the Aria's MM input. This allows for a direct comparison to the Aria's MC stepup transformer input.
I have updated an ARC MCP-33 with some Dynamicaps, Blackgate caps and an IEC. And I am nearly done to replace virtually all the parts (Dynamicaps, Backgates and Texas Components TX2575 resistors) on a Music Reference RM-4. But the real prize has been a nearly completed rebuilt Counterpoint SA-2. This has a new Plitron power transformer, rebuilt PS with Blackgate caps and Texas Instruments TX2575 resistors, and the audio stage also with these resistors. Only 7 other caps need to be replaced (to be done soon) to take this unit to the stratosphere. I also have an unmodded SA-2.
Of the stepup devices above, the modded SA-2 is the BIG winner. The Plitron brings on a level of dynamic contrasts and power that is quite breathtaking. Returning to the original SA-2 transformer was quite a shock. With these power transformers in external chassis connected to the SA-2 through a 6-feet umbilical (removable on the SA-2 side) I can swap between the two transformers for comparison tests.
Before I put in all the TX2575 resistors in the SA-2 audio stage, I compared the modded SA-2 with the rebuilt PS and Plitron to the unmodded SA-2 and Plitron. The updated PS brought on a midrange smoothness and clarity in the trebles, but this difference was not to the same level as the Plitron transformer difference. Michael Elliot was clearly onto something when he discovered the major performance benefit with the Plitron transformers.
Comparing the modded SA-2 with rebuilt PS and Plitron to the Aria's MC input with Sowter transformers resulted in pros/cons for each. The MC transformer input is dead quiet as would be expected. The MC input is very clean with good tonal coherency but after listening to the other devices, there is a noticeable lower treble forwardness with the Sowters. It's not an issue of grain nor smearing but rather the trebles have somewhat of a metallic unnatural sound. One thing I have read here on A'gon over and over is that MC stepup transformers cause serious reduction in dynamics. I have not experienced this with the Sowters in the WV.
I listened again last night to the SA-2 vs. Sowters. The SA-2 was big and bold but not so much in dynamic contrasts but more so in how the tones occupied space. The Sowters bring on a more mellow presentation as if sitting further from the stage, but otherwise there is no significant "failing" of dynamics here. I can easily destroy the system dynamics by simply putting a stock power cord in any number of links in the system.
When I changed back to the SA-2 with updated PS and Plitron, the presentation was dramatic. I had solidity and extension in the lower octaves like not before. This foundation brought on a boogie factor that was exciting. And there was significant depth now unlike before. The size and location of musicians and instruments behind the SoundLab A1 speakers was something to behold. Most significant of all was that piano and voice had incredible energy, the fundamental was very strong with a follow-on bloom. There was incredible body to the midrange.
With all the benefits of the modded SA-2, there was still a slight level of grain and lack of clarity in the trebles which was not an issue with the Sowters. And of course the higher noise level with the SA-2. Not only was there a very slight hum with the SA-2 but the noise level was ever present in the background until the music started. But once it started, the modded SA-2 was in a whole different musicality ballpark than the Sowters.
I then changed 22 resistors to the TX2575 in the SA-2's audio stage. This helped significantly to reduce the treble clarity/grain problem. But the Sowters still outperformed the SA-2 in this one key area. After hearing what the Dynamicaps did to the Aesthetix Io, I suspect this could be huge in the SA-2 as well. Once I update the SA-2's audio stage with Dynamicaps, I can report on my findings.
One important note is that the Jade Hybrid IC did not work well from the SA-2 to the WV. This IC is not shielded and thus I had hum issues. The Jade cable from the SA-2 was very sensitive to cable layout and location to other cables and components behind the rack. Just touching this cable's jacket would cause hum. This meant that I had to go with a shielded IC and all I had was an old old MIT 330 pair. And this is a severely colored and low-resolution cable in other applications I have used so this too could be the cause of the treble grain I have experienced with the modded SA-2. I have had my eyes on a couple of ICs but have not seen them for sale lately. Once I get a top-performing IC here, I can also report my findings.
The Sowters outperform the ARC MCP-33 in the same way they outperform the SA-2. But the ARC with its wimpy 1980s power transformer is simply no match to the SA-2 with the Plitron. The ARC's presentation sounds so small compared to the SA-2. But their midrange magic properties are very similar. The PS in the SA-2 is beefier than the ARC as well. The Amperex Bugle Boy EZ80 tube rectifier in the SA-2 brings on another level of midrange smoothness beyond the ARC. I found a quad of Tele 6DJ8 tubes worked incredibly well in the SA-2 and a mix of Valvo PCC88 and Valvo CCA to be the best combination in the ARC.
No doubt a change to the power transformer in the ARC would be a major benefit to bring life to this unit. The ARC's noise level is a bit lower than the SA-2 but so is its gain by 6 or so db. It's a toss between the ARC and Sowters as the ARC brings on the midrange fullness but of course lacks the clarity of the Sowters. Once I finish the RM-4 rebuild, I will have another data point here. And then I can decide whether or not I want to equip the ARC or RM-4 with a Plitron power transformer. I tried various 7044 and 12AT7 brands in the ARC's PS but these made little difference which was surprising as the SA-2 and WV power supplies react strongly to tube rolling.
I used Dream State Dream Catcher PCs for the SA-2, and WV and a Veridical on the ARC. The tonearm cable was Stealth Hyperphono.
As for the Aesthetix Io Signature, this continues to do midrange textures like no other phono stage. But it lacks the refinement in treble coverage, harmonics follow-on in the trebles, and air/silence between the notes in the middle octaves. No doubt replacing many of the passive parts here would improve these areas, but the Io has so many stages and parts and tubes that there has to be a limit in the level of detail and dynamics to be recovered here vs. the other designs. No matter how addictive the midrange magic might be with the Io, once you hear the new level of detail, either brought on by the modded SA-2 or the Sowters, both into the WV's simplistic MM stage with the tube regulated/rectifed PS, it is tough to go back to the good ol' days.
Once I finalize the SA-2 rebuilt and the RM-4 rebuild I can add more information here. And then I should have some opportunities to hear other full-fledged standalone phono stages. But for now, the nearly completed SA-2 into the WV's MM input is miles ahead of anything I have ever heard from a phono playback setup. The WV's second-to-none line stage plays a major role here as well.
John
Comparing the phono section in the WV has turned into a far more involved process than comparing the line stage. With variables such as loading, gain and noise level, it takes time to find an optimum setting for a cartridge. The Aria's MM stage uses a pair of 6922 tubes for a gain of approximately 35db. This simplistic circuit with the two tubes brings on a level of clarity I have not heard before with phono.
I have not had the opportunity to audition other phono stages. I have wanted to try the Lamm LP2, ARC PH7 and Einstein but I have not been able to locate these. I have once again compared the Aestheix Io signature which has been a long time favorite because of its incredible midrange texture and bloom. And the Io's gain when used with ultra low noise tubes on the input stage allows for use of low output MCs.
For both the Koetsu RWS and Clearaudio Accurate, I found the "best" loading with the Aestheix Io to be 500 ohms. Into the WV's Sowter stepup transformer input, there was not much of a difference between 200, 300, 500 ohms. I tend to run at 200/300 ohms now which mates well with the 7062 tubes in the WV line stage being just a wee bit hot in the trebles.
Solid state phono stages have many attributes that appeal to me, but I just don't like the end result of a solid state input for the first gain stage on even an otherwise all-tube design. Years ago I tried the Klyne and this was very resolving and ultra-low noise but it was just too sterile for me. And the same with the Spectral. So I have stayed with tube based phono stages (other than the ARC PH2 10 years ago) noise and all because of the " musicality" even though the noise level was higher. Perhaps modern solid state designs have improved in this respect.
Another direction I have taken has been to play with external MC stepup devices.....the classic tube products from the 1980s. These can be used directly into the Aria's MM input. This allows for a direct comparison to the Aria's MC stepup transformer input.
I have updated an ARC MCP-33 with some Dynamicaps, Blackgate caps and an IEC. And I am nearly done to replace virtually all the parts (Dynamicaps, Backgates and Texas Components TX2575 resistors) on a Music Reference RM-4. But the real prize has been a nearly completed rebuilt Counterpoint SA-2. This has a new Plitron power transformer, rebuilt PS with Blackgate caps and Texas Instruments TX2575 resistors, and the audio stage also with these resistors. Only 7 other caps need to be replaced (to be done soon) to take this unit to the stratosphere. I also have an unmodded SA-2.
Of the stepup devices above, the modded SA-2 is the BIG winner. The Plitron brings on a level of dynamic contrasts and power that is quite breathtaking. Returning to the original SA-2 transformer was quite a shock. With these power transformers in external chassis connected to the SA-2 through a 6-feet umbilical (removable on the SA-2 side) I can swap between the two transformers for comparison tests.
Before I put in all the TX2575 resistors in the SA-2 audio stage, I compared the modded SA-2 with the rebuilt PS and Plitron to the unmodded SA-2 and Plitron. The updated PS brought on a midrange smoothness and clarity in the trebles, but this difference was not to the same level as the Plitron transformer difference. Michael Elliot was clearly onto something when he discovered the major performance benefit with the Plitron transformers.
Comparing the modded SA-2 with rebuilt PS and Plitron to the Aria's MC input with Sowter transformers resulted in pros/cons for each. The MC transformer input is dead quiet as would be expected. The MC input is very clean with good tonal coherency but after listening to the other devices, there is a noticeable lower treble forwardness with the Sowters. It's not an issue of grain nor smearing but rather the trebles have somewhat of a metallic unnatural sound. One thing I have read here on A'gon over and over is that MC stepup transformers cause serious reduction in dynamics. I have not experienced this with the Sowters in the WV.
I listened again last night to the SA-2 vs. Sowters. The SA-2 was big and bold but not so much in dynamic contrasts but more so in how the tones occupied space. The Sowters bring on a more mellow presentation as if sitting further from the stage, but otherwise there is no significant "failing" of dynamics here. I can easily destroy the system dynamics by simply putting a stock power cord in any number of links in the system.
When I changed back to the SA-2 with updated PS and Plitron, the presentation was dramatic. I had solidity and extension in the lower octaves like not before. This foundation brought on a boogie factor that was exciting. And there was significant depth now unlike before. The size and location of musicians and instruments behind the SoundLab A1 speakers was something to behold. Most significant of all was that piano and voice had incredible energy, the fundamental was very strong with a follow-on bloom. There was incredible body to the midrange.
With all the benefits of the modded SA-2, there was still a slight level of grain and lack of clarity in the trebles which was not an issue with the Sowters. And of course the higher noise level with the SA-2. Not only was there a very slight hum with the SA-2 but the noise level was ever present in the background until the music started. But once it started, the modded SA-2 was in a whole different musicality ballpark than the Sowters.
I then changed 22 resistors to the TX2575 in the SA-2's audio stage. This helped significantly to reduce the treble clarity/grain problem. But the Sowters still outperformed the SA-2 in this one key area. After hearing what the Dynamicaps did to the Aesthetix Io, I suspect this could be huge in the SA-2 as well. Once I update the SA-2's audio stage with Dynamicaps, I can report on my findings.
One important note is that the Jade Hybrid IC did not work well from the SA-2 to the WV. This IC is not shielded and thus I had hum issues. The Jade cable from the SA-2 was very sensitive to cable layout and location to other cables and components behind the rack. Just touching this cable's jacket would cause hum. This meant that I had to go with a shielded IC and all I had was an old old MIT 330 pair. And this is a severely colored and low-resolution cable in other applications I have used so this too could be the cause of the treble grain I have experienced with the modded SA-2. I have had my eyes on a couple of ICs but have not seen them for sale lately. Once I get a top-performing IC here, I can also report my findings.
The Sowters outperform the ARC MCP-33 in the same way they outperform the SA-2. But the ARC with its wimpy 1980s power transformer is simply no match to the SA-2 with the Plitron. The ARC's presentation sounds so small compared to the SA-2. But their midrange magic properties are very similar. The PS in the SA-2 is beefier than the ARC as well. The Amperex Bugle Boy EZ80 tube rectifier in the SA-2 brings on another level of midrange smoothness beyond the ARC. I found a quad of Tele 6DJ8 tubes worked incredibly well in the SA-2 and a mix of Valvo PCC88 and Valvo CCA to be the best combination in the ARC.
No doubt a change to the power transformer in the ARC would be a major benefit to bring life to this unit. The ARC's noise level is a bit lower than the SA-2 but so is its gain by 6 or so db. It's a toss between the ARC and Sowters as the ARC brings on the midrange fullness but of course lacks the clarity of the Sowters. Once I finish the RM-4 rebuild, I will have another data point here. And then I can decide whether or not I want to equip the ARC or RM-4 with a Plitron power transformer. I tried various 7044 and 12AT7 brands in the ARC's PS but these made little difference which was surprising as the SA-2 and WV power supplies react strongly to tube rolling.
I used Dream State Dream Catcher PCs for the SA-2, and WV and a Veridical on the ARC. The tonearm cable was Stealth Hyperphono.
As for the Aesthetix Io Signature, this continues to do midrange textures like no other phono stage. But it lacks the refinement in treble coverage, harmonics follow-on in the trebles, and air/silence between the notes in the middle octaves. No doubt replacing many of the passive parts here would improve these areas, but the Io has so many stages and parts and tubes that there has to be a limit in the level of detail and dynamics to be recovered here vs. the other designs. No matter how addictive the midrange magic might be with the Io, once you hear the new level of detail, either brought on by the modded SA-2 or the Sowters, both into the WV's simplistic MM stage with the tube regulated/rectifed PS, it is tough to go back to the good ol' days.
Once I finalize the SA-2 rebuilt and the RM-4 rebuild I can add more information here. And then I should have some opportunities to hear other full-fledged standalone phono stages. But for now, the nearly completed SA-2 into the WV's MM input is miles ahead of anything I have ever heard from a phono playback setup. The WV's second-to-none line stage plays a major role here as well.
John