The phono stage dilemma

While searching for my ideal preamp, one of my criteria was for this new preamp to have a built-in phono stage.  That turned out to be more difficult, as the only way I could find them was in older preamps, or in new preamps that were way beyond my budget.  I finally caved in to the idea of getting a phono stage.

Yet, which one?  I really wanted tubes.  I still do, to an extent.  But my choices in tubed phono stages was limited within my budget.  And when pressed for a choice, tubes might not be my solution after all.

My first candidate was a Jolida JD9 Mk II.  While build quality seemed acceptable, a few Internet forums mentioned that there were additional upgrades that could take the JD9 up to a higher level.  Upgrades include swapping in premium op amps, better output coupling capacitors, and HEXFRED rectifiers in the power supply.  Not to mention swapping in premium tubes.  I also would have installed my own mono switch on the rear panel.

While I like getting into the innards of electronics with soldering iron and voltmeter, the idea of hacking up a brand new phono stage (and voiding the warranty) did not sit well with me.  Once I did the math, I realized the Jolida would not have been a good investment.

The other candidate in valve land was the Pro-Ject Tube Box DS, which has the unique loading adjustment on the front panel.  It is nicely built, sure.  Yet like the JD9, I could not find any mainstream reviews of this model.  I found a killer deal on it, but decided to pass.  I do not put 100% weight in reviews, of course, but they are a helpful second opinion.

My luck came about by way of a lightly used Phonomena II+ by Musical Surroundings.  Mainstream press?  Yep, Absolute Sound had picked it as an Editor’s Choice.  Other reviews thought highly of it, and especially praised the depth and control in the bass.  Perfect.  It arrived within a week of purchasing it, and looked essentially unused.  The sound is, as you’d expect, phonomenal (sorry).

Loading is quite easy on the Phonomena.  A series of DIP switches on the rear can be set in many combinations to get LOMC loading where you need it to be.  For my Dynavector, I am currently at 59 ohms, but feel that I could probably nudge it down to 50 ohms to really smooth it out.

Running a MM cartridge, though, I have the option of two different resistive loads, and capacitive loads.  The only drawback is that MM loads are limited to 47k or 100k ohms; ear bleeders like the Audio Technica MM carts are happier with different loading, maybe in the 22k range.  The next available setting is 2k ohms.

For gain, there are 13 steps available from 40 to 60dB.

I did notice a bit of “rush” (faint white noise) when turning the volume way up.  I am going to inquire whether this is normal or not, and if a better power supply (than the small wall wart) would help that.  This phono stage uses so little power that a battery power supply may be an option too.

Overall, I have not had much chance to listen to it yet, but the sound is very clean and full-bodied.  If the soundstage was improved with the C-J preamp, this really locks it in further when playing vinyl.  I do want to tweak loads a little more, but it is really sounding nice at 59 ohms.

I will have more impressions over the coming week as I evaluate some high-quality vinyl.

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Preamp upgrade: Conrad-Johnson PV-14L

It only took me 34 years, but I finally have a new (to me) preamp in the system, and I am finally a member of the “valve audio” club.  The PV-14L arrived two weeks ago, and I have been getting familiar with it.  My unit has had the “S2″ upgrade, which features improved caps, Vishay resistors, etc., and a new spec for the tubes.

Having only seen photos of the front panel, I was afraid it was going to be silver.  Instead, it is a pale gold color, which looks nice with the engraved front panel.  Operation is by pushbutton, with most features available via the remote.  Switching and volume are done internally, so worries about oxidizing potentiometers is eliminated.

The tubes were changed out at some point, as the factory spec Mullard M8080s were replaced with the Philips ECG 6C4WAs. For a quick replacement, I ordered in a pair of Tung-Sol 6C4s which were marked for FAA use.  I have the M8080s shipping from the UK, as they are reportedly less microphonic than these 6C4s are.  The Tung-Sols do sound nice in the system, slightly less bright or “etched” sounding than the Philips pair.

One thing I have noticed with this preamp is that the imaging is rock solid.  Instruments are more clearly placed left to right in the soundstage, and vocals are spookily centered between the speakers.  Clearly my speakers are the weak point (for that “last mile” of improvement), yet I can still hear the differences.  One critique of this preamp was weak bass (boooo….), but the S2 upgrade cured that.  The bass is definitely weighty in the improved version.

It also appears to be a good match to the Nelson Pass-designed Stasis amp (Nakamichi PA-7).

The only thing it does not have is a phono stage.  But, that issue has been solved as well…

I will be back with a long-term update, as well as an update once I get the Cardas interconnects built.

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Interconnect Update

I’ve lived with my Silver Sonic cables for several months, which I wrote about this past April.  While they are a clean sounding cable, I am finding the sound to be somewhat thinned out.  Perhaps the silver in the mix is not to my liking.

I have decided to embark on another cable project and make up a few sets of interconnects usinc Cardas 2×21 interconnect wiring.

This particular Cardas cable uses a “golden ratio” of conductors in an arrangement where the inner strands are smaller than the outer.  More notable is that Cardas produces these using litz wire, where each individual strand is insulated with a clear lacquer coating, similar to how windings in a transformer are insulated.  I won’t go into the technical and electrical advantages, but others who have heard Cardas cables mention that they are less bright (some even say they are dark) while the sound is more full-bodied.

This cable is not so expensive that I need to worry about buying enough to make the interconnects.  With that in mind, I am going to go with the Cardas 2×21 and, again, the Neutrik ProFi RCA plugs.  I had considered the Cardas Silver RCA plugs (their lowest cost plug), but it still uses a similar brass core that the Neutrik uses.  Since my RCA jacks on the new preamp (you’ll find out more in a few days 😉 ) will be gold plated, having gold on both the plug and jack will prevent metal mismatches.

Since it has the separate shield, again I will use the floating shield method of building the cables; my Silver Sonic cables remain dead quiet even today.

What’s nice is that I can mix and match these different sets of cables as needed.  If the phono playback is too dull, I can swap in one of the Silver Sonic cables.  If digital is too bright, I’ll stick with the Cardas over the Silver Sonic.

The only caveat with Cardas litz wire is that it requires special preparation–a rosin flux, and tinning.  I may not invest in a solder pot for this project, but the flux is a necessity to flow the solder and melt the lacquer insulation.  (I need to use a heat sink to prevent melting the insulation further up the wire.)

All materials are being ordered next month.  With new equipment arriving, it is a perfect time to recable the system with everything out of the rack.

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Dynavector XX2 Mk. II

XX2-1I was without the 17D3 for a couple of months, as I had returned it for a minor warranty issue.  With no new stock forthcoming, the distributor got in touch and offered me an upgrade to the XX2 Mk. II.  It would be factory rebuilt, and I could either borrow it long-term until the 17D3 came in, or keep it if I liked it; the cart would go into their demo stock for use in trade shows.

Turns out I’ve kept the XX2.  Given that I can now actually see the cantilever, it is juuuust a little bit easier to align. From what I can tell, it uses the same basic cartridge body as the 20X2.  Yet the motor and everything else is improved.

As with the 17D3, the XX2 outtracks that piece of shit Ortofon 2M Black I formerly owned.  I will say that from first impressions, I still think I prefer the sound of the 17D3–it is more neutrally balanced.  Granted, the XX2 has not broken in yet, and I have also not been able to further adjust the cartridge loading in the pre-preamp.  I find it to have a slightly “peaky” sound, almost as though I can hear the resonance of the aluminum body manifesting itself in the music.  Not that it is a glaring problem–it’s subtle. And it very well may go away once it breaks in.

After a few months and a more careful alignment, I will have more impressions on this fine cartridge.

 

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Cables, cables…

IMG_20150416_023644Ever since I dumped those crappy Audioquest snake oil cables back to Amazon, I needed to find interconnects.  I checked many brands, and let’s just say that the prices are crazy on some of them.  And each company has its own spin on cables.  Some are pure silver.  Others, silver-plated copper.  Some are pure copper.  Many are bundled together.  Some are braided, like the Kimber Cables.  And the RCA plugs…brass or copper base metal, silver plating, copper plating, cryogenically treated, etc.

Staaahp!

From the marketing hyperbole, you’d think some of them would make you shit magical rainbows.

Having read around somewhat, I came up with the idea of using the Silver Sonic cables from DH Labs.  They base their cables on a copper core with a silver plating.  The premise is that lower frequencies travel deeper into the core of a wire, while higher frequencies reside closer to the skin.  With that in mind, they use the copper core to provide better conduction of the lower frequencies, with the silver assisting the top end.  The wires arrived with an attractive blue jacket and directional arrows.

For RCA ends, I used the Neutrik ProFi plugs.  They come with a unique pressure-fit strain relief system, as well as a unique spring-loaded grounding shield that contacts the RCA jack first when being plugged in, and loses contact first when being removed.

While I don’t believe that the metals in the wire are directional (it is, after all, non-magnetic), the arrows do come in handy.  These cables come with two conductors, plus shield.  I hooked these up in a floating shield configuration.  The red and white conductors are connected respectively to the hot and ground on each end.  The shield, however, is connected only at the source end of the cable.  This prevents a potential ground loop situation caused by the shielding.  The arrows then help you connect the correct end to the source and destination.

Other than some of the lettering flaking off, the cables turned out nicely.

On first listen, they do have a clean overall presentation, perhaps a little bit leaner than I’m used to.  The RCA plugs fit snugly on the jacks.  As for noise, they are dead quiet.

Time will tell as to how they eventually sound once I am used to them.  I made three sets so far.  Next time, I may order up some cable sleeving to neaten things up a bit, perhaps even combining the two cables into one sleeve for ease of routing.

Stay tuned.

 

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