best preamp ever - cost is no object

carlos, i'll be happy to address the acrolink mexcel AC cord, as i was the one who found it (in my own system, with the X0-1D2 in context). the sound was dramatically improved, with better frequency extension and tonal accuracy in the midrange.

it is wholly inaccurate to state that power cords are 'pseudoscience.' geometry & shielding affect EMI / RFI, conductor purity / gauge / stranding vs solid core affect tonal expression, connector quality affect frequency extension (particularly the bass), and connector plating also influences tonal expression. ---i am speaking from my own skeptical but impossible to ignore experiences. (in my day job, i'm forced to revise my opinion hour by hour, sometimes 180degree changes, so i've no set agenda on what is the right answer, which is how i approach audio)

you have to have an open mind and a good system to hear these things. which are you lacking?

and, fwiw, using a "tone-control" graphic equalizer is not the right answer if pursuing SOTA performance. as one designer noted "there is no perfect part", and you advocate adding an entire electronic box full of integrated circuits (and associated nasties & loss of signal accuracy) in to achieve your ends. yes, you may improve the tone (and that is the bigger element to long term satisfaction), but i can virtually guarantee that you're losing microdetail (not important to some, but greatly enhances the musical virtual reality effect)

when you find an IC that passes a signal without any attendant exaggeration or loss in a 20-20khz band, please let us all know. i think there's some several hundred high-end audio electronic manufacturers who would be interested in your finding.

Ryan,
You are talking to someone with degrees in both Physics and electrical engineering. I believe that you do accounting by profession correct?

As I said in my post above:

It is not that I think that all tubes and power cords sound the same; on the contrary I indeed believe that they sound different and that you and others are indeed “hearing” a difference. What I content is that these differences can be achieved in a much more elegant way than trial and error. The same end results can be achieved through the use of knowledge of mastering/recording techniques, physics, acoustics, psychoacoustics, electronics and the use of high-end studio equipment and techniques which will result in predictable, repeatable, defeatable and scalable phenomena.

When it comes to electronic circuit and design trust me you can't even begin to imaging who you are challenging as I design complex electronics circuits for NASA and HP among others. You have no idea what you are talking about with this statement:

When you find an IC that passes a signal without any attendant exaggeration or loss in a 20-20 khz band, please let us all know. i think there's some several hundred high-end audio electronic manufacturers who would be interested in your finding.

For one, have you ever heard of an instrumentation Op-amp?

As far as your question:

You have to have an open mind and a good system to hear these things. which are you lacking?

Quiet frankly neither. I have invited you countless number of times to come and judge my system and my approach for yourself and you refuse it. Let's try it again. Come over this Saturday and I will return the gesture by going to your house on Sunday to listen to what you bring to the table! Fair enough?

Carlos, frankly I do not believe you have any degree in physics, which by the way was one of my undergraduate degrees. I would believe an engineering degree, in particular in EE, where you are taught that all is know about electronics. And as far as designing for NASA, forget it. I know an ex-NASA electrical engineer who now does tube audio design and who has an appreciation for the limits of our understanding, which your education seems to have been remiss in giving you.

Good luck with your tilting at windmills book and don't bother to send me a copy.

You don't seem to understand that no one cares what you have to say, as you seem wholly ignorant.

My take on the "sound" of different manufacturered tubes, whether NOS or current production is that each brand has a "house" sound. For example, the famous NOS Mullard Square getter, 1959 ECC83, known for it's amazing musicality( especially in the midrange) and warmth might be a little too warm in some circuits. I prefer in my 1959 Pilot 402 receiver( bedroom system) an early 60's Siemens double post ECC83, only because it is a little more neutral with better extensions and it seems to compliment the Siemens E84L power tubes. Yet in my VAC Monoblocks, I am using an inexpensive($6.00) stock Philips 12au7aw( 1989) tube because it sounds the best as the driver tube for my current production Chinese-made Shuguang KT88-98 power tubes, which are an amazing power tube. The Shuguang company has come up with a marvelous power tube with this new KT88-98. And they're priced very reasonably as well. I've read that the solid plate version might be better in some respects) Perhaps tube-rolling can be associated with fine-tuning the tone, but there is much more than that taking place. As a musician, besides tone, which is very critical, I look for timbre, proper soundstage, imaging, extended yet refined and delicate highs, natural midranges( palpable voices, accurate portrayal of a well-miked piano) and midbass and subterranean bass that is accurate without being bloated. I have listened to a number of excellently tested preamp tubes that have a difficult time in portraying accurate and realistic bass. Of course, I could always get a fancy equalizer like Carlos to "force" that bass to be accurate. But, in my humble opinion, any equalizer in the circuit, as Rhyno mentioned, will in some way affect the signal to degrade the purity of the recorded sound. I suppose it's a matter of trade-offs, but I'd rather fine tune my room acoustics without the use of an in-line equalizer. Any true red-blooded audiophile has my blessings in finding the right tube to roll if he pleases. Fortunately, the designer of my VAC amp, Kevin Hayes, is not only a brilliant engineer, but has a very good ear as well and his factory tubes are "voiced" perfectly to suit my discerning ears. I had to learn the hard way with Mucho $$$ in tube rolling.

Ryan,
Where did I mention a graphic equalizer? I have never own a graphic EQ but that is exactly what a Cello Palette is; try to tell Tom Jung of DMP, Shawn Murphy of Hollywood/movie scoring fame, Mrs. Wilma Kozart of Mercury Living Presence fame that their $25K Cello Audio Palettes are a piece of junk! It is used in many of the recordings that you use to evaluate system as a "reviewer".

I hate to say it but I think that you have clearly over-stepped your area of expertise and are quickly getting yourself in trouble when you try to discuss electronic circuit design and mastering studio gear with me. Don't say I didn't warn you as I'm known to be ruthless.