Stereomour II (in progress)

[denti alligator]

I'm a total idiot! I had to move the amp from one side of my credenza to the other to have the RCAs in reach, and when I moved it I forgot to re-plug it in! 

So it's going... I'm using the mono Pet Sounds to set the balance. It's sounds glorious! FAR, FAR more bass. Richer sound, wider soundstage, more detail. Etc.

[denti alligator]

By the way, I've got the hum down to completely inaudible, even with my ear up to the speaker. Should I cancel my DC filaments order, or are there other benefits to that upgrade, too?

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi68.tinypic.com%2F212tyeb.png&hash=20f54036dd1b70c3e3ea1d1f875a26399356e70a)

[denti alligator]

Listening to Kitajenko conducting Shostakovich's first symphony on SACD now and it's jaw dropping!!

All due respect to the S.E.X. 2.0, even with MQ all-nickel iron upgrade, but this leaves that wonderful amp in the dust. Glad to have it as a headphone amp--that's for sure!

[denti alligator]

All this excitement about the sound of this amp made me forget that I had wired it for 4ohm, and still need to try 8ohm to see what difference I hear. Could it sound better?

[denti alligator]

It's the damping factor. Most speakers are designed to operate best with an amp that has a very high damping factor; SETs usually have a DF between 2 and 4. This makes the response sensitive to variations in speaker impedance. Peaks when the impedance is high are limited, but notches when the impedance is low are unbounded.

In the Forte II graph, the biggest dropout would be in the bass where it drops below half of the nominal 8 ohms. There will be a smaller peak in the upper midrange where the impedance is high. Room acoustics are significant, especially in the bass, so sometimes just moving the speaker around will adequately compensate. That's why I suggested trying both options and listening.

Paul, if I understand you correctly, I am more likely to get better bass at 4ohm, but may lose something in the upper middle, whereas with 8ohm I may lose some bass?

I've got it at 4ohm right now and it sounds pretty nice all around. I'll be away for a week, but when I return I'll re-wire to 8ohm and listen.

[denti alligator]

OK, I've re-wired for 8ohms. The difference is subtle, but so far it seems like there's less rich bass. Whatever strengths this brings me might not be worth the trade-off. Honestly, I'm still so floored by the sound that I have a hard time focusing in on whatever slight drawbacks there might be in the different ohm wiring.

[tsingle999]

How did you like the clarity caps vs solens?

[denti alligator]

How did you like the clarity caps vs solens?

Haven't put the Solens in yet. Will try that later. Thanks for helping me out with those ClarityCaps, though!

[denti alligator]

Went back to 4ohms. I think I like that better.