low voltage check?

[Mach2]

I have just finished building my Mainline, and at the very last voltage check my build doesn't seem to hit the mark at all the 275V measure points, in particular, the +275vDC on the PSB, the IA on both the C4S board all read 253V instead of 275V. All the other numbers are spot on.

I couldn't resist to do the bias the tubes and plug in a headphone to see if there is any sound coming out, and yes there is. The sound is too good to be true, actually, compared to my Crack and S.E.X... Only one thing I noticed, is that with my HD650, the volume is quite low, I have to turn up all the way to -18db level on the coarse volume pot (and all the way up on the fine pot) to get to my usual listening volume. Is that caused by the lower than expected voltage?

Is there anything wrong with not hitting the 275V mark?

-PH-

[Paul Birkeland]

You probably have slightly lower line voltage than normal, and 253V is about 10% low, which is OK.

To get more output into HD-650, be sure to use the high impedance switch setting.

-PB

[Doc B.]

-18dB isn't really "all the way". You still have 12 more steps, one third of the available range.

[Mach2]

Thanks, Doc and PB! So I guess my build is good! I was a little worry when not hitting the mark on those 275V measure points, as I don't see the blurb about the usual "up to 15%" error in the manual, and that I perfectly hit every other readings.

Not really complaining about the volume. I tried my 600Ohm T1 cans and while I need to turn one more notch on the coarse pot to -9db to get to my usual listening level compared to the HD650, I don't think I ever need to turn "all the way" up to 0db unless I want to damage my eardrum.

The Mainline is really spectacular. Have to admit that I did not set a high expectation with my first try after reading Loquah's review, but the Mainline gave me a bigger WOW than the first time I tried the Crack. Oh the delicious mid!

-PH-

[Doc B.]

Yeah I was a little surprised at Loquah's initial impression. For me the first listen to Mainline was like "BAM - that's what I'm talking about!" But I think his point about how a lot of the improvement is in taking away stuff that isn't really in the recording but maybe added by other amps is particularly good and explains why one might not hear a dramatic difference at first listen. Perhaps I was more impressed at first listen because that was what I was hoping to experience, in a sense hearing less rather than more. Everyone hears differently and that's part of the reason we have three different headphone amps. I can certainly appreciate his liking of the sense of depth the S.E.X. amp adds. My goal with the Mainline was to make it as uncolored as possible so it would be a useful tool for critical listening.

[mcandmar]

I instantly understood where Loquah was coming from, and what he was trying to convey.  It reminded me of when i jumped from mid range Grado 80i/225i headphones to the higher end Alessandro Ms-Pros, my initial impression was a bit underwhelming as they didn't really stand out, but after a few days and weeks that neutrality and refinement is what made me fall in love with them.  I adore them now for that, and when i wrote a review of them i described them as very refined and smooth, but honest with nothing added, and nothing taken away. A few traits i noticed Loquah used to describe the Mainline, it was at that point i thought ahh crap it does sound perfect.

The only thing that did put me off was his comments about the S.E.X. amps greater sense of depth, its that sense of space and separation i love the most about it, and would miss that dearly.

The Mainline was always bit of an unknown for me but now Loquah has put a face on it and made it a known quantity i am confident i would love it, and i'm sure there will be many more that come away with the same conclusion.  Though the S.E.X. amp will be a tough act to follow, especially now i have mine dialed in with a few quality caps, its just sublime.

[Mach2]

When I said I have a low expectation before trying out the Mainline for the first time from Loquah's review, I meant that I expected to not be instantly impressed by it. I would expect to spend a few days with it to understand what a "natural" or "uncolored" sound sounds like. Instead I said "Holy cow!" after 5 seconds. I secretly hoped for a marriage between the S.E.X and the Crack to combine the transparency of the S.E.X and the musicality of the Crack, and the Mainline gave me exactly that.

The only thing that did put me off was his comments about the S.E.X. amps greater sense of depth, its that sense of space and separation i love the most about it, and would miss that dearly.

My initial impression is that I think Loquah's comparison of the S.E.X and the Mainline sense of depth as the first row and the third row experience is spot on. I do love the awesome depth the S.E.X offered. That combined with the HD800 and classical music is pure sex. The Mainline offers a slightly less intense experience, a "perfectly right" one. Depend on your mood, it may actually be a more pleasant experience.

[Mach2]

Just want to say that after listening exclusively to the Mainline for a few days, I went back to my Crack and... yeah I think I understand the "natural" and "uncolored" signature description now, and why "less is more" is good thing.

-PH-