TONEAudio Magazine
New member
- Joined
- Apr 19, 2013
- Messages
- 391
- Thread Author
- #1
<p><strong><a rel="attachment wp-att-11181" href="http://www.tonepublications.com/review/ava-ultravalve-vacuum-tube-amplifier/attachment/1-43/"><img class="alignleft size-full wp-image-11181" title="1" src="http://www.tonepublications.com/media/154.jpg" alt="" width="600" height="377" /></a>The finger snaps on Thomas Dolby’s “The Ability to Swing” hang in midair between the speakers, as Dolby’s highly processed yet ethereal vocal enters the mix.* “It isn’t worth a bean, if you haven’t got the ability to swing,” he declares.</strong></p>
<p>Indeed, the six-figure system assembled in room two is in full swing right now, but the amplifier powering the Sonus faber Guarneri Evolution speakers is the humble AVA Ultravalve, not the $65,000 Octave Jubilee monoblocks I’ve been using for some time.* This is truly an amazing amplifier.* If I powder-coated the chassis a certain shade of blue-green, slapped an Air Tight badge on the front panel and told you I paid five figures for this little jewel, you’d believe me—it’s that good.</p>
<p>With so much excitement about the vinyl resurgence of the last few years, some of you have forgotten how popular vacuum tubes have also become lately.* Yet, in the midst of these newer products sprouting up, it’s easy to forget some of the players that have been around for quite a while.* Audio by Van Alstine (AVA) is that “other” amplifier company in Minnesota—Audio Research is located nearby—and it is a perfect example of a manufacturer that has quietly gone about its business making great products without a ton of fanfare. *And you rarely see products from AVA for sale on the secondary market.* The company obviously has a legion of loyal customers,</p>
<p>No matter how much time I spend with mega-dollar power amplifiers, I always love a variation on the Dynaco Stereo 70 theme. *While I’ve never heard one that I <em>didn’t </em>like, there are big differences between them.* Some have a softer, warmer presentation and definitely embellish more than others; the original ST 70 is the prime example of that voicing.* With these types of amps, your best recordings don’t sound much better than your worst, but everything sounds somewhat liquid and dreamy—not a bad place to hang your hat if you have a modest system, or a lot of MP3s.</p>
<p><strong>Tube Through and Through</strong></p>
<p>Frank Van Alstine has been at this game for a long time. *He started out modding and repairing Dynaco electronics 30-plus years ago, and revamped the ST 70 circuit so much over the years that it is now truly his own design now.* The Ultravalve is still based on a pair of 6CA7 output tubes (EL34 or KT77 tubes can be used as well), but it does not have a switch for triode mode, fancy power output meters or anything that distracts from the amplifier’s performance.* And its price is right: $1,999 puts one in your hot little hands.</p>
<p>Like the original ST 70, the Ultravalve uses a 5AR4 rectifier tube and a pair of more readily available 6GH8A small-signal tubes in place of the now long-obsolete 7199 tubes in the ST 70, which is fetching premium prices online.* The Ultravalve is one of the first power amplifiers I’ve listened to with which I just don’t feel the need to roll tubes.* It sounds just fine as is, and a little bit of research shows that there aren’t a lot of variations on the 6GH8A tube anyway.* Perusing Mr. Van Alstine’s board on the AudioCircle forum shows him to be a practical man, so I just enjoyed the amp’s stock tubes.</p>
<p>I do upgrade the power cord to a Cardas Clear cord for my review, only because that’s what I use with everything else and we value consistency here.* The Ultravalve does benefit slightly from the upgraded power cord and from being plugged into a Running Springs Dmitri power conditioner.* But keep in mind that none of this is necessary to enjoy the Ultravalve.</p>
<p>Removing the bottom panel of the highly polished stainless steel chassis reveals tidy workmanship throughout, again showing that AVA sticks to the basic layout of a ST 70: driver circuitry on a well-thought-out PC board and the rest of the amplifier wired point to point. *There is a switch on the rear panel to float the ground, as well as three binding posts for 4-, 8- and 16-ohm speakers; this is my only gripe with the Ultravalve.* It really could use some beefier binding posts for those of us with bigger speaker cables. *My solution is just to re-terminate with bananas plugs.</p>
<p><strong><a rel="attachment wp-att-11182" href="http://www.tonepublications.com/review/ava-ultravalve-vacuum-tube-amplifier/attachment/2-38/"><img class="alignleft size-full wp-image-11182" title="2" src="http://www.tonepublications.com/media/248.jpg" alt="" width="600" height="411" /></a>Ace of Bass and Dynamics</strong></p>
<p>Bass control is a big part of the equation here.* The original ST 70 has a puny power supply and it shows up in the playback, with the bass response lacking dynamics and sounding wild and wooly.* An original Conrad-Johnson MV50 isn’t much better.* An original Marantz 8B has a more liquid midrange but still falls short down under.</p>
<p>As brilliant as the Sonus faber Guareri Evolution speakers are, like any high-performance Italian product, they are a bit picky about what you feed them.* Just like my Fiat Abarth getting grumpy when filled with anything less than premium gas, the Evos need current and control to give a stellar performance and sound as big as they should.</p>
<p>And when delivering Nine Inch Nails’ “Help Me I Am in Hell,” the Ultravalve sounds <em>big.</em> I move the amp out into room one, with the KEF Blades (with their 90-dB-per-watt sensitivity), and it sounds damn big, with guitars floating around the soundstage and the heartbeat at the end of the track filling the listening room.* Upping the game with a much more densely recorded track, “Mr. Self Destruct” from NIN’s album <em>The Downward Spiral</em>,<em> </em>I find that the Ultravalve not only keeps the groove of the driving synth bass well intact, but it also does not lose the focus.* The amp starts and stops on a dime as Trent Reznor brings the music to barely a whisper, only to audibly assault us again and again with a huge ball of sound and dynamics.</p>
<p>It’s still hard to believe I’m listening to a $2,000 amplifier. *For those of you in the audience thinking that it’s sheer insanity to put an amplifier like this in a system like this, I submit that it’s the only way to see what its performance envelope truly is.* Daft Punk’s <em>Homework</em> lights up the Blades and I can turn the volume up to the point where I feel like I’m back in New York at Fashion Week.* All that’s missing is the catwalk.</p>
<p>The Ultravalve carefully follows Stanley Clarke as he rips up the fretboard on “Bass Folk Song No. 7,” clearly demonstrating its ability to keep the Blade’s 9-inch woofers in control.* The amp reveals Clarke’s delicate touch on the fretless bass, and it never gets sloppy, slow or wooly.</p>
<p><strong>It’s also Got Top</strong></p>
<p>The Ultravalve is ultra quick, even when playing a less-than-superb recording, like The Stooges self-titled album, on which the amp keeps its composure, provided you don’t turn the volume past the point of soft clipping.* Rather than getting harsh, like many other low-powered tube amplifiers we’ve auditioned, the Ultravalve begins to suffer from a collapsed soundstage.* This degradation is slow at first, but the amp then quickly slides into the same flat, brick-walled sound that plagues many of today’s digital recordings.* But if you keep the Ultravalve within its comfort zone, you’ll be handsomely rewarded.</p>
<p>Miles Davis’ “Diane,” from <em>Steamin’ with The Miles Davis Quintet</em>, proves open and spacious, with Philly Joe Jones’ brushwork on the drums exquisitely rendered, as Davis floats through the soundstage.* This amplifier becomes more convincing the longer you listen; about an hour is required for it to open up completely, but it is still damn good two minutes after initial turn on.</p>
<p>Perhaps the only stretch for the Ultravalve while paired with less than highly efficient speakers comes when asking it to reproduce large-scale orchestral pieces or electronica at club levels.* Prokofiev’s suite from <em>The Love for Three Oranges</em> taxes the Ultravalve as the large kettle drums reach full throttle, requiring listening at less than what might be considered a live level—but how often do you do that?</p>
<p><strong><a rel="attachment wp-att-11183" href="http://www.tonepublications.com/review/ava-ultravalve-vacuum-tube-amplifier/attachment/3-34/"><img class="alignleft size-full wp-image-11183" title="3" src="http://www.tonepublications.com/media/343.jpg" alt="" width="600" height="586" /></a>Back to Earth</strong></p>
<p>Using the Ultravalve with similarly priced components is highly rewarding.* It is fully capable of anchoring a modestly priced but high-performance system.* Mating the amp to a Conrad-Johnson PV-12 preamplifier (with CJ’s recent capacitor updates), an Oppo BDP-105 universal player and the Rega RP6 turntable, with a pair of KEF LS50 speakers, proves breathtaking—especially for a relatively inexpensive system like this one.* But you’ll be surprised just how damn good the Ultravavle sounds as part of a no-holds-barred system.</p>
<p>While the 35 watts per channel of the Ultravalve may not be enough juice for everyone, if that much wattage will work for you, I cannot recommend this amp highly enough.* The level of resolution, tonality and bass control this amplifier offers for $1,999 is unmatched by anything I’ve ever experienced at this price point.* I am very proud to award the Ultravalve one of our Exceptional Value Awards for 2013.* I’m keeping this one!</p>
<p><strong>AVA Ultravalve Vacuum Tube Amplifier</strong></p>
<p>MSRP: $1,999</p>
<p>Audio by Van Alstine (AVA)</p>
<p><a href="http://www.avahifi.com/">www.avahifi.com</a></p>
<p><strong>Peripherals</strong></p>
<table width="100%" align="left" class="easy-table easy-table-default "><tbody readability="4.5"><tr readability="2"><td><strong>Analog Source</strong></td>
<td>SME 10 turntable * *Sumiko Palo Santos cartridge * *Aesthetix Rhea phonostage</td>
</tr><tr readability="2"><td><strong>Digital Source</strong></td>
<td>dCS Vivaldi stack * *Oppo BDP-105</td>
</tr><tr readability="2"><td><strong>Preamplifier</strong></td>
<td>Conrad-Johnson PV-12c1 * *Nagra Jazz * *Robert Koda K-10</td>
</tr><tr readability="3"><td><strong>Speakers</strong></td>
<td>Dynaudio Confidence C1 * *KEF LS50 * *KEF Blade * *GamuT S9 * *Sonus faber Guarneri Evolution</td>
</tr><tr><td><strong>Cable</strong></td>
<td>Cardas Clear</td>
</tr></tbody></table>
[Source: http://www.tonepublications.com/review/ava-ultravalve-vacuum-tube-amplifier/]
<p>Indeed, the six-figure system assembled in room two is in full swing right now, but the amplifier powering the Sonus faber Guarneri Evolution speakers is the humble AVA Ultravalve, not the $65,000 Octave Jubilee monoblocks I’ve been using for some time.* This is truly an amazing amplifier.* If I powder-coated the chassis a certain shade of blue-green, slapped an Air Tight badge on the front panel and told you I paid five figures for this little jewel, you’d believe me—it’s that good.</p>
<p>With so much excitement about the vinyl resurgence of the last few years, some of you have forgotten how popular vacuum tubes have also become lately.* Yet, in the midst of these newer products sprouting up, it’s easy to forget some of the players that have been around for quite a while.* Audio by Van Alstine (AVA) is that “other” amplifier company in Minnesota—Audio Research is located nearby—and it is a perfect example of a manufacturer that has quietly gone about its business making great products without a ton of fanfare. *And you rarely see products from AVA for sale on the secondary market.* The company obviously has a legion of loyal customers,</p>
<p>No matter how much time I spend with mega-dollar power amplifiers, I always love a variation on the Dynaco Stereo 70 theme. *While I’ve never heard one that I <em>didn’t </em>like, there are big differences between them.* Some have a softer, warmer presentation and definitely embellish more than others; the original ST 70 is the prime example of that voicing.* With these types of amps, your best recordings don’t sound much better than your worst, but everything sounds somewhat liquid and dreamy—not a bad place to hang your hat if you have a modest system, or a lot of MP3s.</p>
<p><strong>Tube Through and Through</strong></p>
<p>Frank Van Alstine has been at this game for a long time. *He started out modding and repairing Dynaco electronics 30-plus years ago, and revamped the ST 70 circuit so much over the years that it is now truly his own design now.* The Ultravalve is still based on a pair of 6CA7 output tubes (EL34 or KT77 tubes can be used as well), but it does not have a switch for triode mode, fancy power output meters or anything that distracts from the amplifier’s performance.* And its price is right: $1,999 puts one in your hot little hands.</p>
<p>Like the original ST 70, the Ultravalve uses a 5AR4 rectifier tube and a pair of more readily available 6GH8A small-signal tubes in place of the now long-obsolete 7199 tubes in the ST 70, which is fetching premium prices online.* The Ultravalve is one of the first power amplifiers I’ve listened to with which I just don’t feel the need to roll tubes.* It sounds just fine as is, and a little bit of research shows that there aren’t a lot of variations on the 6GH8A tube anyway.* Perusing Mr. Van Alstine’s board on the AudioCircle forum shows him to be a practical man, so I just enjoyed the amp’s stock tubes.</p>
<p>I do upgrade the power cord to a Cardas Clear cord for my review, only because that’s what I use with everything else and we value consistency here.* The Ultravalve does benefit slightly from the upgraded power cord and from being plugged into a Running Springs Dmitri power conditioner.* But keep in mind that none of this is necessary to enjoy the Ultravalve.</p>
<p>Removing the bottom panel of the highly polished stainless steel chassis reveals tidy workmanship throughout, again showing that AVA sticks to the basic layout of a ST 70: driver circuitry on a well-thought-out PC board and the rest of the amplifier wired point to point. *There is a switch on the rear panel to float the ground, as well as three binding posts for 4-, 8- and 16-ohm speakers; this is my only gripe with the Ultravalve.* It really could use some beefier binding posts for those of us with bigger speaker cables. *My solution is just to re-terminate with bananas plugs.</p>
<p><strong><a rel="attachment wp-att-11182" href="http://www.tonepublications.com/review/ava-ultravalve-vacuum-tube-amplifier/attachment/2-38/"><img class="alignleft size-full wp-image-11182" title="2" src="http://www.tonepublications.com/media/248.jpg" alt="" width="600" height="411" /></a>Ace of Bass and Dynamics</strong></p>
<p>Bass control is a big part of the equation here.* The original ST 70 has a puny power supply and it shows up in the playback, with the bass response lacking dynamics and sounding wild and wooly.* An original Conrad-Johnson MV50 isn’t much better.* An original Marantz 8B has a more liquid midrange but still falls short down under.</p>
<p>As brilliant as the Sonus faber Guareri Evolution speakers are, like any high-performance Italian product, they are a bit picky about what you feed them.* Just like my Fiat Abarth getting grumpy when filled with anything less than premium gas, the Evos need current and control to give a stellar performance and sound as big as they should.</p>
<p>And when delivering Nine Inch Nails’ “Help Me I Am in Hell,” the Ultravalve sounds <em>big.</em> I move the amp out into room one, with the KEF Blades (with their 90-dB-per-watt sensitivity), and it sounds damn big, with guitars floating around the soundstage and the heartbeat at the end of the track filling the listening room.* Upping the game with a much more densely recorded track, “Mr. Self Destruct” from NIN’s album <em>The Downward Spiral</em>,<em> </em>I find that the Ultravalve not only keeps the groove of the driving synth bass well intact, but it also does not lose the focus.* The amp starts and stops on a dime as Trent Reznor brings the music to barely a whisper, only to audibly assault us again and again with a huge ball of sound and dynamics.</p>
<p>It’s still hard to believe I’m listening to a $2,000 amplifier. *For those of you in the audience thinking that it’s sheer insanity to put an amplifier like this in a system like this, I submit that it’s the only way to see what its performance envelope truly is.* Daft Punk’s <em>Homework</em> lights up the Blades and I can turn the volume up to the point where I feel like I’m back in New York at Fashion Week.* All that’s missing is the catwalk.</p>
<p>The Ultravalve carefully follows Stanley Clarke as he rips up the fretboard on “Bass Folk Song No. 7,” clearly demonstrating its ability to keep the Blade’s 9-inch woofers in control.* The amp reveals Clarke’s delicate touch on the fretless bass, and it never gets sloppy, slow or wooly.</p>
<p><strong>It’s also Got Top</strong></p>
<p>The Ultravalve is ultra quick, even when playing a less-than-superb recording, like The Stooges self-titled album, on which the amp keeps its composure, provided you don’t turn the volume past the point of soft clipping.* Rather than getting harsh, like many other low-powered tube amplifiers we’ve auditioned, the Ultravalve begins to suffer from a collapsed soundstage.* This degradation is slow at first, but the amp then quickly slides into the same flat, brick-walled sound that plagues many of today’s digital recordings.* But if you keep the Ultravalve within its comfort zone, you’ll be handsomely rewarded.</p>
<p>Miles Davis’ “Diane,” from <em>Steamin’ with The Miles Davis Quintet</em>, proves open and spacious, with Philly Joe Jones’ brushwork on the drums exquisitely rendered, as Davis floats through the soundstage.* This amplifier becomes more convincing the longer you listen; about an hour is required for it to open up completely, but it is still damn good two minutes after initial turn on.</p>
<p>Perhaps the only stretch for the Ultravalve while paired with less than highly efficient speakers comes when asking it to reproduce large-scale orchestral pieces or electronica at club levels.* Prokofiev’s suite from <em>The Love for Three Oranges</em> taxes the Ultravalve as the large kettle drums reach full throttle, requiring listening at less than what might be considered a live level—but how often do you do that?</p>
<p><strong><a rel="attachment wp-att-11183" href="http://www.tonepublications.com/review/ava-ultravalve-vacuum-tube-amplifier/attachment/3-34/"><img class="alignleft size-full wp-image-11183" title="3" src="http://www.tonepublications.com/media/343.jpg" alt="" width="600" height="586" /></a>Back to Earth</strong></p>
<p>Using the Ultravalve with similarly priced components is highly rewarding.* It is fully capable of anchoring a modestly priced but high-performance system.* Mating the amp to a Conrad-Johnson PV-12 preamplifier (with CJ’s recent capacitor updates), an Oppo BDP-105 universal player and the Rega RP6 turntable, with a pair of KEF LS50 speakers, proves breathtaking—especially for a relatively inexpensive system like this one.* But you’ll be surprised just how damn good the Ultravavle sounds as part of a no-holds-barred system.</p>
<p>While the 35 watts per channel of the Ultravalve may not be enough juice for everyone, if that much wattage will work for you, I cannot recommend this amp highly enough.* The level of resolution, tonality and bass control this amplifier offers for $1,999 is unmatched by anything I’ve ever experienced at this price point.* I am very proud to award the Ultravalve one of our Exceptional Value Awards for 2013.* I’m keeping this one!</p>
<p><strong>AVA Ultravalve Vacuum Tube Amplifier</strong></p>
<p>MSRP: $1,999</p>
<p>Audio by Van Alstine (AVA)</p>
<p><a href="http://www.avahifi.com/">www.avahifi.com</a></p>
<p><strong>Peripherals</strong></p>
<table width="100%" align="left" class="easy-table easy-table-default "><tbody readability="4.5"><tr readability="2"><td><strong>Analog Source</strong></td>
<td>SME 10 turntable * *Sumiko Palo Santos cartridge * *Aesthetix Rhea phonostage</td>
</tr><tr readability="2"><td><strong>Digital Source</strong></td>
<td>dCS Vivaldi stack * *Oppo BDP-105</td>
</tr><tr readability="2"><td><strong>Preamplifier</strong></td>
<td>Conrad-Johnson PV-12c1 * *Nagra Jazz * *Robert Koda K-10</td>
</tr><tr readability="3"><td><strong>Speakers</strong></td>
<td>Dynaudio Confidence C1 * *KEF LS50 * *KEF Blade * *GamuT S9 * *Sonus faber Guarneri Evolution</td>
</tr><tr><td><strong>Cable</strong></td>
<td>Cardas Clear</td>
</tr></tbody></table>
[Source: http://www.tonepublications.com/review/ava-ultravalve-vacuum-tube-amplifier/]
