Monthly Archives: March 2013

System Upgrade Part 1: the Musical Fidelity X10-D tube buffer stage

Tubes?  Yes, tubes. Valves.  Vacuum tubes.  The stuff that your grandfather’s hi-fi had inside its mysterious guts.  Tubes have also been praised for decades for having a certain amount of musicality that solid state devices could not touch.  There are still more than a handful of audiophile components that use tubes, although most are priced into the stratosphere; nice sounding tubes are not cheap either.  Consider that my budget is currently “ground level” as compared to stratosphere, and you can imagine that my dream of ever owning tubes would likely never come to fruition.

mf10dla[1]However, there are ways to get that “tube” sound into your system.  I had no problem with my analog playback.  In fact, I was pretty much avoiding digital over the past couple years due to how unpleasant it sounds.  The idea of trying either a new DAC (digital to analog converter) or a tube buffer stage somewhere in my system was in the back of my head.  I perused a lot of the eBay listings for examples of either, but upon discussing it with an audiophile pal of mine, he decided to mail me one of his extra Musical Fidelity X10-D tube buffers.  He had just purchased a spare on eBay, put a new set of tubes in it (more on those shortly), and shipped it my way to evaluate.

I have had the buffer plugged in now for at least two weeks straight–it uses minimal power when idle yet, keeping the tubes warm, it tends to “lock in” when the components have all stabilized.  Surprisingly, the outside of the case hardly feels warm at all when the unit is idle.  Even after a listening session of a few hours, the outside is only mildly warm.

Connecting the X10-D into my system was a challenge.  At first I had it between the CD player and preamp, but now I have it in the external processor loop of the preamp (a Hafler DH-101) in order to use it with more of my sources, including vinyl.

I did have reservations.  I did not want something to act as a Band Aid for what I feel are shortcomings in digital reproduction.  That, and I did not even know if I would be able to hear a difference.  My hearing (and my patience) is not what it used to be.  But along with the tube buffer and a handful of other changes, I was able to change the sound of my system for the better.

Finally, I have been able to hear what all the fuss is about: tubes sound niiiiiiiiice!  The effect is subtle.  A casual listener might not even hear the difference, and I admit the difference is not something that reaches out and hits you over the head immediately.  It is subtle.  The pleasures unfold the longer you listen.  You start noticing things. You notice that the soundstage blooms beyond the speakers where it never used to, yet other images between the speakers tend to sound more localized.  (A sound dead-center between both speakers comes at you strongly as dead-center now.)  There is also a fullness and body to the music I hadn’t heard previously: there seems to be more “meat” to the sound now.  With the tube buffer being a new concept to me (tubes…in an audiophile system, not an old dusty hi-fi in my parents’ basement), I’ve found myself trying familiar CDs to see how much difference the buffer makes.  I do notice that a lot of rock studio recordings see minimal improvement, while earlier rock/pop recordings, and especially vocal and acoustic music, really make the tubes glow.

That leads us to tube rolling.  As of the date of this writing, I have not yet had any alternate tubes to try, but the current tubes are a pair of National (Matsushita) 7DJ8 tubes that sound quite nice in the system.  They are a little on the bright side before they are broken in, but tame down nicely once they have had a few hours on them.  This tube is a recent find; it may be worth finding more of these before the price heads up to that stratosphere I mentioned earlier.  My loaner pal says that his preferred tube in this buffer is the Amperex 7308 JAN (joint army-navy) tube with gold plate pins.  This buffer works with a variety of tubes, as you can tell:  6DJ8, 6922, ECC88, E88C, 7DJ8, 7308, E188CC, and likely a few others.

The point of entry for this model of buffer is between $100 and $150, depending on whether or not good tubes are included.  Count on maybe $50 or more for a good matched pair of tubes, and budget for an extra pair of interconnects as well.

 

 

System Upgrades

I was getting a bit impatient with the sound of my main audio rig: it’s bright, it’s not much fun to listen to, it just wears on me. Digital in particular: excruciating.  Even the best mastered CDs out there just left me gritting my teeth.

For what it’s worth, the components of my system include the Pioneer DV-45A as a digital source, the Hafler DH-110 preamp fed into a Carver M-500t power amp, a pair of Grafyx SP-10W speakers, and a good vinyl rig.  There are other components, but these play an important role in the system tweaking I have done.

Seeing that each piece seemed to play a small but important part, I am going to list them separately in future posts.  So far, four changes have made an improvement that is noteworthy, even on subtle levels.