It just does not work this way - if Kcin is saying experienced IO users have verified and many of them have found that to their liking, the only way to find out if it does it for you is to try it, and not to go by such theory. You just cannot sum up warm and neutral and linear theoretically to get to the right balance
I know; there is no substitute for trying it myself.
 
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I know; there is no substitute for trying it myself.
Sorry, you are not getting away with that generalisation as it will be true of everything.

The case is there is no case for rejecting the idea of trying it yourself based on theory and saying it will not work for you. It should be no.1 priority in your tube swaps. Chances are you are going to end up loving it.
 
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When the 1mV output Grado Epoch 3 gets installed on my Reed 5T I may return to playing with NOS tubes in the V1 - V6. 1mV output should take a lot of pressure off any NOS tube noise issue.
Then you can remove tube v5 and v6 and the gain will be reduced to 50dB. That's good: less tubes = less noise don't forget the jumper.
 
Then you can remove tube v5 and v6 and the gain will be reduced to 50dB. That's good: less tubes = less noise don't forget the jumper.
My Io has volume controls, so I would not do that.
 
My Io has volume controls, so I would not do that.
OK. then that won't help you because the overall gain always remains at 86dB. I would ask the manufacturer whether this is still possible
 
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OK. then that won't help you because the overall gain always remains at 86dB. I would ask the manufacturer whether this is still possible
86db gain? That seems excessive, no wonder you have noise issues. Very surprising that the Io does not have adjustable gain even with the volume controls. Too much gain inevitably leads to noise.
You should consider 5751 in place of 12ax7 in the first gain stage. Gain (mu) of 70 compared to 100 for 12ax7. The early triple mica versions were built for the military and are very low noise. I like the Sylvania triple mica black plates, Sylvania Gold brand triple mica gold pins, or the G.E. triple mica black plates.
 
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86db gain? That seems excessive

Not at all. Your phono stage uses a step-up transformer. That is a very different situation.
 
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Not at all. Your phono stage uses a step-up transformer. That is a very different situation.
My Coincident does use step-ups and also has volume controls (no line stage used or needed). Produces 66db of gain, more than enough for .3mv or more cartridges even with my low sensitivity Acoustats. No noise even with your ear pressed against the panels even at loud volume.
 
I was surprised that the Mullards were too "plump and rich" for me! Far worse than that, they gave the music a bit of Valium.
I concur with the neutrality of Telefunken’s as an excellent candidate for a phono stage … however which Mullards are you and @Kcin referring to ? I certainly would not consider Mullard M8137 / CV4004 to be as you describe .

Ok … One last try at neutrality with a soupçon of desirable harmonics :

IMG_0008.png
IMG_9997.jpegThe Red Print 1960’s being high grade examples .

 
86db gain? That seems excessive, no wonder you have noise issues. Very surprising that the Io does not have adjustable gain even with the volume controls. Too much gain inevitably leads to noise.
You should consider 5751 in place of 12ax7 in the first gain stage. Gain (mu) of 70 compared to 100 for 12ax7. The early triple mica versions were built for the military and are very low noise. I like the Sylvania triple mica black plates, Sylvania Gold brand triple mica gold pins, or the G.E. triple mica black plates.
I wouldn't do that without measuring the 5751 tube have a lower impedance , as that can influence on the accuracy of the RIAA equalization.
It really depends on whether passive, split or active riaa is .i don't know the shematics
 
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I wouldn't do that without measuring the 5751 tube have a lower impedance , as that can influence on the accuracy of the RIAA equalization.
It really depends on whether passive, split or active riaa is .i don't know the shematics
Yes definitely check with Aesthetix to insure the tube is compatible before trying. I shoud have mentioned this!
Does work fine in my Coincident.
 
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For Io V8

IMG_0553.jpeg
 
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I am surprised that V7 (RIAA buffer or something) and V8 (output stage) make a noticeable, if subtle, sonic difference when V1, V2, V3, V4, V5 and V6 remain stock.

I do hear differences (a touch more naturally smooth, and a more real, human-like midrange) from the Amperex USN CEP 7308 and RCA 5692 redbase. I like them!
 
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So . . . I am pretty much pencil down.

The ASC "Resnick-ators" are en route, and they will replace the standard TubeTraps in the front corners.

I should try to move the panels a little bit closer together.

I may order a small Torus isolation transformer just to isolate for peace of mind the power supplies on a legacy electric line separate from the electrical system for the listening room.

I would love to try Wavac 833.

I would like to add a pair of big subwoofers low-passed at about 25Hz.

I could try to play with a little diffusion on the front wall behind each panel.

I could fiddle more with NOS tubes in the gain stages of the Io.

Eventually I probably will replace the Pangea stands with Vintage Audio Specialties Nothing Stands.

But that's it. (And I probably won't do most of these.)
 
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I listened to a variety of genres (Billy Joel, Elton John, Symphonie Fantastique, For Duke, Anette Aavik, Eva Cassidy, Carole King, Black Sabbath, Sarah McLachlan) for several hours tonight.

I am happy with how this whole shebang is sounding. But I keep thinking that this system does not sound like the great majority of what we hear in most dealer audio salons these days. This system is not about low noise floor, crisp leading edge transients, black background, maximizing detail, slam, clearly delineated sonic images, maximizing resolution or extended frequency extremes.

In my personal preference ordering I am not willing to accept any harshness, any metallic-ness, any edginess, any dryness for more apparent detail or for seemingly more resolution. Harshness, metallic-ness and edginess derail my connection to the music, my suspension of disbelief.

Please see revised Post #4,781, below.
 
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In my personal preference ordering I am not willing to accept any harshness, any metallic-ness, any edginess, any dryness for more apparent detail or for seemingly more resolution. Harshness, metallic-ness and edginess derail my connection to the music, my suspension of disbelief.
Do you think a lot of people have a preference for harshness, metallicness, edginess?
 
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Do you think a lot of people have a preference for harshness, metallicness, edginess?

It's probably more that they don't care, or just don't hear it when it's there.
 
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It's probably more that they don't care, or just don't hear it when it's there.

must be picking up different cues from live then to suspend disbelief
 
Do you think a lot of people have a preference for harshness, metallicness, edginess?
Excellent and obvious point, thank you. Sorry, as usual for me posting when tired is ill-advised.
 
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