Red Wine Audio Part II, Isabella Renaissance Edition Preamplifier

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Have I mentioned that I’m a huge fan of red wine? I mean, generally speaking and all that.  Yeah, well, it’s true. It’s something of a long-time passion of mine and let’s just say that if I could find a way to relo out to Napa, I’d be gone so fast the keyboard wouldn’t even spin.

I’ve already waxed autobiographically rhapsodic on the Part I of this review, so allow me to refer you there for your daily glass of me. Ahem. But the point there, stands — I’ve been a fan of Red Wine Audio for years now, so when I was lucky enough to land a review set, I was thrilled.

Spoiler alert: they rock!

Red Wine is like … an analogy

One of my go-to high-end audio analogies relies heavily on wine. Specifically, on wine reviews. If there’s ever been a “domain” more susceptible to the vagaries of personal taste, it’s wine. There’s Wine Spectator, Wine Enthusiast, and many (many) other outlets out there, ready to share their experiences and thoughts. I’ve subscribed to both of these, at various points, and found the reviews interesting but almost never actually helpful — the wines they liked were hard to find in my neck of the woods, and when they were available, usually weren’t All That. When I found The Wine Advocate, late in the whole process, I wasn’t expecting much. But when I happened to try a recommendation from their editor and lead reviewer, Robert Parker, and was floored. I tried another and was floored again. This is the point that I’ve attempted to make repeatedly with every commentary on reading reviews and reviewers — this is still a matter of taste, and if you haven’t found a reviewer — entertaining though he may be — that actually lines up with your personal approach, then you’re probably wasting your time.

I say all that because it may be that what like and look for may not be what you like and look for. And that’s okay. It also makes it a pretty good place to start.

Looking at preamplifiers

In another review, I asked a simple question: what is a preamplifier? Like many “simple questions”, the answer wasn’t. To make a long story short-ish: a preamplifier is a volume knob and an input selector. Simple, right? Okay, so let’s keep scratching: a preamp differs from a linestage. That is, a preamp usually adds amplification of some sort (current or voltage). I’m going to wave my hands here because any more and we’ll wander too far for this digression, but what I’m attempting to get at is that this amplification (at the least) is especially for some source that desperately needs it — think ‘phono’, and you’re on the right track. Me? I prefer to think of preamps as two-fers; they tend to do more than one job. Now, it’s a fair point that just about every element mentioned directly or referenced obliquely includes a rabbit-hole’s worth of variations in approach that all purport to advance some particular aspect of performance to “all new levels”, and all that is terrific fun. But the Newest New Thing in preamp thinking is the idea that DACs, with their on-chip/integrated volume controls, make preamps/linestages completely redundant — and eliminating them is wildly beneficial to the overall sound quality of the system they’re removed from.

Okay — hopefully, you’ll pardon me while I inject myself into this thread with some personal biases. Ready? Okay: for me, I do like some of the DACs I’ve heard when used as preamps. Generally, the sound of the system can be very open and transparent at loud-to-very-loud, and that’s all well-and-good. The main issues I have with this amp-direct approach is that many DACs don’t really “do” volume control all that well, which means that at lower volumes (read: “normal listening”), the transparent sound washes out and the music becomes veiled. Personally, I think this is a bad thing. Volume control aside, this magic-killing blah-ing effect may also be due to the fact that the DACs don’t really have a particularly robust analog output stage (quite commonly, they don’t). The final nail in the coffin (for coffins that need three nails, at least) is that going amp-direct doesn’t really leave me much in the way of options for a turntable, a tuner, a tape player, or any other way to get me to my tunes — and before you go there, I have to say that any DAC that digitizes perfectly good analog signals before decoding them again seems pointless and silly. But that’s me. 

So, a real, honest-to-goodness pre that does all the things a pre does and does well and has a DAC along for the ride? Color me intrigued! There’s just something tempting about simplifying and streamlining … really tempting … even if the idea of ‘integrated solutions’ tends to be better than the implementation.

Anyway, that’s all a long way to go before saying that there are a few things I want a preamp to do for me (with the built-in assumption here that YMMV). One? It has to connect up all my crap. I’m not getting rid of my turntable! Two? It has to be transparent. Actually, I’d prefer “invisible”, but I’ll take transparent. Failing that, well, we’ll have to see where that goes. Three? It has to sound good at all volumes, not just concert levels or at a whisper. Four? Well, it couldn’t hurt to be easy to use and not awful to look at!

Isabella takes a bow

Isabella with her doting daddy and a pair of AKG K701 headphones

Vinnie Rossi is the guy behind Red Wine Audio, and as the founder, head, and main worker bee, he gets some liberties. Take product names, for example. Here, he didn’t have to reach far — “Isabella” is his eldest daughter. Which makes it rather important that the preamplifier named after her be worthy. You know. Or else. No pressure! 

What’s new with Isabella is the Renaissance Edition, a 2013 upgrade that Vinnie brought to the entire product line. The RE incorporates a couple of new things, including a brand-new look anchored by a classy-looking wood face and sides. There’s also some big chromed-out knobs, and an all-new metal remote. It’s a classy look and one that sits well on the rack. On the inside, the Isabella RE sports a brand new layout, a redesigned battery system, and a tube stage that can take the Russian 6H30 “super tubes”. 

And then, things get really nifty.

As I mentioned, with this new RE revision, connoisseurs can add a DAC to Isabella, derived from the stand-alone Bellina product. This features Vinnie’s favorite (and secret!) NOS DAC chipset, which is good for that low-res MP3 crap, up to those finely ripped CD-quality files you’ve been hoarding like squirrel getting ready for winter. Don’t deny it. Anyway, the input is right on the back next to the analog ins – well, there are three digital ins, actually, including a Toslink, a BNC S/PDIF, and an asynchronous USB input.

If you’re feeling particularly frisky, you can opt for the “high-res” DAC, called the “Pro” option, which will let you play your fancy hi-res audio files, with support for up to 24bit depths and 192kHz sampling. Perhaps most awesomely, the Pro option actually includes both DAC chips and you can flip between them whenever the mood suits. Yeah! Sweet, right? You know that’s cool. Admit it!

Not a digital guy? Well, analog junkies can add a fully-functional phono stage, based on the stand-alone Analogica phono preamplifier. The input can be moving coil (60dB, with a variety of loading options) or moving magnet (40dB at 47k) — and the configuration options are modifiable and readily accessible underneath the preamp’s top panel, which is easily removable with a trio of thumbscrews.

And if you’ll pardon the slip into late-night TV ad barker mode, “That’s Not All!” Nosiree, we haven’t mentioned the headphone option! Yes indeedy – you can get your choice of XLR or phono-plug adapters, pushing up to 5 watts into your cans. As it’s implemented here in the Isabella, this headphone option builds off the two dual-triode tubes that the Isabella has in the preamp, instead of the single dual-triode that the stand-alone head-amp, the Cassabria, uses. More! Better! Tubes!

Best of all: did I mention you can get all three options in the same preamp? The DAC plus the phono plus headphone amp? All in one. See? RWA has got your “full-function”, right there! Winner, winner, chicken dinner!

The unit that I got did not have the headphone, which is a shame, and someone Who Shall Remain Nameless did something untoward to the phono board, which makes two shames.  There’s an old saying in Tennessee — I know it’s in Texas, probably in Tennessee — that says, fool me once, shame on — shame on you. Fool me — you can’t get fooled again. Whatever.

Anyway, I’ll restrict my comments to the Isabella as I used it, which is a straight-up linestage and I’ll flavor that particular steak with some comments about the DAC, which I spent time with. Let’s start with the latter.

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Isabella is a Pro (DAC)

As I mentioned, you can get your preamp tricked out in one of two digital flavors. The first is the NOS DAC, which adds a $1,000 to your Isabella as well as a bunch of inputs. If you go nuts, you can upgrade that to the Pro DAC for another $500, but before you get all twitchy, recall that the stand-alone Bellina is $2,000, so either option offers a significant up-front savings. Like hot fudge taking that ice cream scoop into Sunday Heaven, if you opt for the Pro, you also get the NOS; a toggle switch on the back of the box will let you pick which DAC chip you’re going to run with.

Vinnie has clearly stated his preference for his vintage NOS chip, which only supports up to 96kHz sampling and no, this may not be as limiting as a cognoscenti’s jerking knee might seem to indicate. Yes, everyone and their grandmother seems to be talking about high-res digital — okay, maybe not Gran. But even if that were true, the vast majority of my audio files are not high-res and I hardly think I’m alone in this. Lossless rips from CD are still 44.1kHz, and if you’re an iTunes or Amazon Digital customer, everything there is lower still. This preference for the bleeding edge is very clearly only going to trouble folks chasing after super-fidelity as opposed to those looking to play their music. And no, it’s not that there’s anything wrong with that — that is why RWA makes the Pro DAC available, after all. The Pro DAC supports all the latest sampling for PCM conversion — up to and including 24/192 over an asynchronous USB transport.

Cutting directly to the chase, I’ll offer that the NOS converter has a sweet, almost vintage sound — warm, smooth, and terrifically forgiving. If you’re an iTunes warrior, this may well be the chip for you. I found it to play all my low-res files with style and grace, especially rendering the less favorable recordings with a bit more meat on the bone. This was entirely welcome, especially with most of my 80’s rock collection.

Flipping the toggle switch on the back of the box to engage the Pro DAC brought a more transparent sound, with greater apparent extension, top-to-bottom. To my ear, the midrange took a half-step back into the soundstage, at least as compared to the NOS DAC, and the whole presentation seeming to be more coherently seamless. Detail retrieval is also better with the Pro DAC, and little soundfield cues, like the crickets buried in “Roadhouses and Automobiles” from Chris Jones’ album of the same name, are brought forth clearly and appropriately. Bass performance on either DAC is quite satisfactory, but the Pro DAC seems to reach a bit deeper. Air and separation are also more “modern” in the Pro DAC, with good helpings of both.

For whatever it’s worth, I compared these on-board solutions to one of my favorite outboard solutions, namely, the $3,500 Auralic VEGA. This little DAC is very fancy and features file support up to and including double-rate DSD files. Comparing this to the on-board converters in the Isabella is not entirely fair as it is three times more expensive, but it shows its capabilities at the frequency extremes where it’s more grippy and more precise laying out the players on the stage.

$1,500 for a DAC is not inexpensive by any means, but it’s also a far cry from some of the more absurd offerings being bandied about in Computer Audio. As part of an “integrated solution”, the Pro DAC offers very good sound in an extremely convenient package. Spending more may well yield sonic gains, but that means more cables, more space, and more power. If I were looking for a consolidated space-saver and/or I was jumping into high-end computer audio, this would be a very easy place to start.

Isabella, out in front

Where I see the Isabella shining most brightly is right where she belongs, holding your audio system together. With three inputs on the version I had, I was able to play vinyl, digital files, and Sonos-driven Internet radio. The connections were solid, the casework was tidy and very pretty, while the sonic presentation was just superb. It’s one of the best preamps I’ve heard, and at this price, it has “value” etched all over it.

There were two things I noticed right away, well, aside from the warm look, the clean lines, and the dainty frame. The first was the soundstage. My reference preamplifier is the Control Unit EXT1 from BorderPatrol, and the reason it’s my reference is for this neat little trick it pulls out of its magical hat: an unbelievably huge, open, and airy field of sound that pushes back, to the sides, and most awesomely, top and bottom. It’s like going to see a movie on an IMAX screen instead of a “mere” movie screen. It’s incredible. It’s also $12,250. The Pass Labs XP-30 comes closest to the overall scale, but layers in quite a bit more detail; it’s also $16,500. The Sonus Veritas, at almost $17k, takes a different tack and presents something like a triumvirate in preamp thinking — tonally very dense with a real sense of scale and drama.

And there’s a reason I’m talking about these uber-expensive preamps in the context of a $4,000 unit. Ahem. I think the Isabella tends more toward the BorderPatrol unit, which itself splits the difference between the XP-30 and the Genoa. That is, its soundstage is huge, beautifully presented, with great detail and just-lovely tone. The fact that the Isabella might not quite eclipse the monsters in my preamp Trinity isn’t an indictment at all (well, not against Red Wine Audio, anyway). Placing the Isabella on my own mental price/performance curve does unkind things — if there’s an inflection point, where big jumps in price no longer yield linear or even predictable gains in performance, I think I just found it. Yes, there’s a reason this preamp has won awards. 

Okay, so that’s the first thing. Where the Isabella leaves all of her expensive cousins in the dust is silence. The Isabella is the quietest preamp I’ve used with any of my external sources — no hiss, no hum, no buzz, nothing is coming out of the drive units on my 96dB DeVore Fidelity Orangutan O/96 loudspeakers. Bing bing bing! Score! For those filling in the bubbles on the Scantron sheet, that translates into fantastic detail retrieval, specificity and placement of players, and some just plain silly dynamics. This background, this inky-black, blackety-black, Blackie Blackerstein and His Infinity Chorus, is a little disconcerting. But mostly, it’s just sweet.

Stepping back a pace or three, I find myself thinking that the main difference a really good preamp makes over a DAC-used-as-a-pre, aside from basic connectivity, is in the sense of scale. I find that many DACs don’t really do justice to complex music at volumes. It can get … thin. Precise, perhaps, with an ability to track individual notes, but still, a little sonically threadbare. Here, with “big music” like Fanfare for the Common Man from Reference Recordings’ catalog of work from the Minnesota Orchestra, the Isabella handles the score with deft grace. The clarion brass section rings out and like a call to war, the cymbals strike sparks and you feel the skin displacing on the thunderous timpani strikes. Pomposity at its best.

Speaking of which, have you had a chance to check out Todd Garfinkle’s work with MA-Recordings? Todd’s been making the audio trade-show circuit for years now so it’s hard to qualify him as a secret, but, well, maybe he is. Anyway, he’s found, recorded, and put out an enormous corpus of audio jewelry that’s truly remarkable — the best bit is that he records in “live spaces”. Think “churches” and you’re on the right track. It’s spatial cues, with natural ambiance courtesy of reflective surfaces, resonances and sheer space — that is so wild. It’s like a subtext woven throughout all his stuff. I’ve been listening to Será una Noche’s second album, La Segunda, for a little while now, and I’m mesmerized by the fullness of the sound I hear. With the Isabella out front, the music lifts out of that super-quiet background and makes this album a 3-D immersion. Goose bump time.

Another MA-Recordings favorite is actually a studio album, in the sense that it was recorded in a studio, but instead of being a mixed-to-hell piece, you get the feeling that this could have been a cozy library with the Mathias Landæus Trio almost casually riffing their way through one of my favorite jazz albums, Opening. Over my amp-direct trials, warmth is what stands out here — and no, not “tonal warmth” — I mean, timbral warmth. The piano can be cold-sounding. But not this piano. And that was different. The piano here is a big, heavily used instrument in the same way that a favorite old coat or well-worn boot is “used”; there’s this deeply rich, burnished and resonant timbre that is absolutely arresting. I … might have drooled on myself a little bit during this session, and trying to set down my thoughts is a bit like fighting my way through a thicket of cliches. I’ll offer this: This is a great performance and the fact that the recording is excellent just ices the cake.

Playing music quietly is hard to do, apparently. In preamp-less system, this may have more to do with digital attenuation than with noise in the gain stages — in specific point, turning the volume down on the Auralic VEGA, when run directly into a pair of Red Wine Audio Liliana monos, got dull pretty quick. Using the Isabella as my volume control, and running the VEGA into that first, let me keep more music in my music, especially when I couldn’t run the system wide-open. Pear Jam’s poor, inarticulate Eddie Vedder on the recent remaster of Ten is still a muddled mess — but, happily and remarkably, it’s much less so. “Jeremy”, for example, is a great track, and one that’s unfortunately still relevant. Revisiting this album, some 20+ years after its original release, is not a happy walk down memory lane for me. It’s a late-night play, maudlin, and best served with a bottle of bourbon and a bucket of ice — and Isabella gave me my clearest window yet into the lyrics. Not that anyone will ever be able to parse “Black” without a cheat sheet, but whatever.

Before I move on, I want to call special attention to a tiny toggle switch on the back panel, right between the outputs. From Vinnie:

… Note that on the low gain setting (0dB), the tubes are not giving any voltage gain, but they are giving current gain. So the voltage from the source is not amplified, but the current is and this is one of the reasons why you hear a greater sense of scale and PRaT with a good active preamp vs. a passive solution.

Me? I used the no-gain for the 96dB DeVores and to good effect. But on the 85dB Magnepans, the extra 12dB were very welcome! I think the purist will probably opt for the no-gain option on the off-chance the circuit is quieter without it, but I didn’t notice any issues with noise — just in usable range on the dial with the higher-sensitivity speakers.

Fun with tubes

I had the good fortune to get a few other tubes to play with. First up was a pair of JJ 6922 tubes, which at $30/pair, qualify as the cheap and cheerful of the set. They do nothing wrong and nothing particularly spectacularly well. Call it the baseline.

The Isabella actually comes with a pair of 6H30 tubes, known for being very linear, dynamic and extended, almost to a fault. If you’re looking for a tube that builds bridges between the virtues of solid-state and tubes, then this is your Huckleberry.

The JAN tubes (I think this pair, shown below, is a Philips but I also have a pair of Sylvanias I like even more) are NOS, obviously, and have very nice tone. A little less-quiet than the others in the set, they’re far-and-away the most interesting, at least in terms of tone and color.

The last of the set is the Genelex Gold Lions. Super-duper tube, new stock and easy to find, it’s a nice alternative to the 6H30. Linear, quiet, and a bit warmer than the bigger tubes. $85/pair will get you a terrifically matched set.

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Sovtek 6H30, Gold Lion, JAN/Philips, JJ

Isabella, by acclaim

juliarulesmallThe Isabella, as a preamplifier, is one of those few audiophile products with price tags in the multi-thousand-dollar range that actually force me to reach for synonyms for ‘bargain’. It’s not cheap. No. I feel like I have to keep saying this, but it’s worth pointing out that $3,995 for anything is just a whole lot of money. That said, audio’s high-end does some completely insane things with pricing, so yes, the scale we use to measure is a little different than other scales. On this scale, $4k is warranted if and only if the little box does what it does on par with boxes that are far more expensive, and this is exactly what the Isabella does. It’s expensive, fine. But it’s really good at what it does and you usually have to spend a crap-ton more to get to this level. This is the very definition of The Julia Rule. The fact that this component specifically (and it’s cousins from RWA, generally) also allows you do dispense with power conditioning and exotic power cables only skews that result even more.

Another side-point and largely unrelated to what’s gone before is the size of this component — it’s tiny. It’s the size of a Stephen King novel, and not one of the ones where he clearly clubbed his editor to death, either. It’s almost modest. It says something when the small size of a component strikes me as an altogether unqualified good thing — usually, my preferences tend to be for gear that’s as ambitious as a grad student’s doctoral work, which as we all know, is measure in tonnage. But there’s a reason for that bias — mass typically means that the designer has invested in a healthy analog output or power supply or something. Something that usually translates into audio deliciousness, bass authority, or perhaps just competency in design. So, when I get a piece of gear that has all the sonic hallmarks of awesomeness but only weighs, say, ten pounds, I’m all aflutter. I think I might have mentioned this in the Liliana piece, but boy howdy does my back love this RWA gear. Battery power, with its crazy-fast delivery, sure has some serious advantages, and a distinct lack of mass is one of them.

EditorsChoiceSmallThe other, of course, is the that background. A complete lack of noise and grunge is the “killer app” for RWA and may well be largely responsible for the other bits of audio joy that flow from these components. Me? I found it breathtaking and entirely addicting.

Verdict? Winner!

This is a great preamplifier — highly recommended.

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DAC board inside the Isabella preamplifier
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Analogica phono board inside Isabella preamplifier

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Thumbscrews for easy tube-access

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That tiny toggle is the hi/lo gain switch

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About Scot Hull 1063 Articles
Scot started all this back in 2009. He is currently the Publisher here at PTA, the Publisher at The Occasional Magazine, and the Executive Producer at The Occasional Podcast. There are way too many words about him over on the Contributors page.

9 Comments

  1. Great review! Sometimes your writing style is for me like what good hops do to IPAs. And to my brain as well. I’m wondering what you mean by low-level listening, because I often sit 4 feet from my speakers. At other times I have the option of about 6 feet. I’ve been told that Alps potentiometers do lose a lot of detail lower down in the dial. Now I’d guess this is going to vary a bit between different speakers, but how quiet can you play this before you start to lose something? I ask because I’m considering the Red Wine Sig57. Thanks.

    • You start to “loose something” right away with most volume controls, Alps pot included. But I lost more with the digital control on my Vega.

  2. Love the review, I my case, I use a benchmark DAC 1 as a preamp into Bel Canto amp in my desktop system, and while I am content with the performance, the red wine seems to be a great upgrade. You know this is a crazy hobby LOL. Now this is the issue as somebody who was raised in the 80’s I dont have a clue about TUBE gear. I don’t even know where to start learning. I heard somewhere (dont know if its true) that after a while you have to change them, etc, etc. Anyway I was wondering if you can point me to a place that I can learn something about Tube Gear and if you think this Red Wine would be a good upgrade to my “vintage” DAC 1. Thanks, keep the good work. Maybe we will call you “Full Time Audiophile” one day. Ismael

    • I think tubes can be scary when you know nothing, but don’t be afraid! If this would be your first step into tubes, it’ll help that the vendor is very accessible (Vinnie is really easy to talk to and very patient). If you want to chat with another tube guy, Jim McShane of McShane Designs has been a good resource for me.

  3. “Spending more may well yield sonic games”

    I think you probably meant to say “gains.”

  4. Sweet! Both the Isabella and the review. Very nice photos, too. This is going on my want list for sure! Along with the Orangutan O/96 speakers. Just as soon as I win the lottery. In the meantime, can you recommend a nice value red wine to drink that will enhance listening on my current system? Ha! Keep up the great reviews. Thanks!

  5. There’s a misprint in the last paragraph before the “Isabella is a pro DAC” section heading. You call it Liliana, instead of Isabella.

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