Link Spotlights

Link Spotlights
The Pinnacle of The Electrostatic Sound

Tuesday, November 21, 2017

Audiophile Review!
Pass Labs INT-60
Stereo Integrated Amplifier
“A Top-Notch Combo Amp
Nets Blend of Sound, Features”



Brevis...
Price: $9,000 MSRP
Likes: perfect mix of clean sound, features
Dislikes: should have an onboard phono pre
Cool Factor: that big ‘ole volume knob!
More Info: Pass Labs INT-60

by John Gatski
  In 20 years of testing Pass Labs amps and preamplifiers, I always get a little excited when a new one hits the market. The super Class A XS-150 amp and the HPA-1 headphone amp were recent examples of products that I effusively waxed positive. And now the INT-60 integrated amp joins the list.
  The INT-60 is an integrated that not only lets you listen to any kind of music with that point 8, MOSFET output ease, but it is very accurate in its transmission of Hi-Res audio, such as 24/192 PCM and DSD. Much like the INT-30 from half a dozen years ago, the INT-60 quickly became a favorite in my listening room, despite its heft.

Features
  Priced at $9,000, the INT-60 is a 60-watt Class A-A/B stereo amp (30 watts in Class A), utilizing the Pass Supersymmetry .8 design implemented a few years ago. The .8 amps run higher into Class A and offers a subjective listening character that is both linear, yet super smooth, with a wide, two-channel presentation when using the best speakers.
  The basic .8 structure of the INT 60 is the same one used in the X30.8 stereo amp, but with a high voltage to get the extra power.
  The INT-60, indeed, is one of the best sounding integrated preamp/amplifiers I have ever reviewed. It is tough to better the INT-60 with separates in this price range. Even if you spend a bit more, you probably will not top it. Incredible detail, width and depth in the expansive stereo image, plus quick bass response.

  The INT-60 features four sets of inputs: three sets of RCAs and two balanced XLRs (inputs one and two have both). There are also a set of XLR and RCA variable outputs if you just want to use the preamp section with another amp. Five-way binding posts complete the connection section.
 Of course, high quality parts abound: precision matched MOSFETS, massive power supply and lots of heat sink to keep this significantly Class A running integrated cool.
  Pass Labs Designer Wayne Colburn says the INT-60 is a quality integrated amp that offers medium-sized power and bridges the dollar gap between the old INT-30 and the INT-150.8. Plus,   it is an integrated that eases the complexity of having to run separates if you don’t want the fuss.
  “I suppose in some ways an integrated is a compromise,” Colburn says, “but it also eliminates a set of cables and simplifies things. I use an INT-60 as my home amp.”

All the line connections most audiophiles need

  Colburn noted that the INT-60’s sonic improvements stem from extra power and a better preamp stage then the previous .5 integrated amps. Spec-wise, the INT 60’s numbers include 35 dB of gain. Distortion well south of 1 percent and a damping factor of 150. Power consumption at full power is, gulp, 375 watts.
  Pass’ classic front mounted current meter shows relative amp operating mode. With 30 watts Class A on tap, you seldom will ever be in Class A/B. The meter’s blue light hue looks really cool in the dim light.
  A Class A/AB amp means a big power supply, combined with a beefier output section, plus it has an onboard line preamp. Translation: this is no lightweight amp at over 70 pounds. The amp’s dimensions  are: 19-inches wide, 21.2-inches front to back and 7-inches tall.

The set up
  I auditioned the Pass INT-60 with numerous speakers, including the MartinLogan Impression electrostatics, Audio Physics Tempo tower, Amphion  Argon3S small stand speakers and PSB T3s.
  Other amps on hand included a 2004 Bryston 14B SST II, Rogue Audio Medusa Class D/tube hybrid,  Pass XA30.5 30 watt Class A stereo amp, and my very old original mid-1960s Macintosh MC275. Review preamps included a Rogue Audio RP-5 tube preamplifier, Coda line preamp and a slew of DAC/preamps including Benchmark DAC3-HGC, Mytek Digital Manhattan II, Oppo Sonica and Prism Sound Callia.


$6,000 PSB T3's were a perfect mate for the INT-60


  I also routed a VPI Player turntable through the INT-60, with the help of a phono section in the Rogue Audio RP-5. The Hana hi-output, moving coil “E” cartridge was a good match for the Pass amp/speaker combos that I auditioned.
  Per usual, interconnects and speaker cables were all from Wireworld, and the AC accessories were courtesy of Essential Sound Products, based in Michigan.

The audition
  The first speakers we powered with the Pass INT-60 were the MartinLogan Impressions, a new model that replaces the Montis. With a slightly bigger panel, and dual-powered eights with digital crossover, the 45-inch tall Impression is a wonderfully detailed, airy, accurate electrostatic that kick solid bass down 32 Hz.
  Since the Impression has a powered subwoofer section, I was mostly focused on how well the INT-60 resolved the low-to-high midrange and treble sounds. And the unanswered question regarding the new integrated was whether the addition of a newly designed preamp changed the texture of the .8 amp section sound that I knew quite well?
  The .8 amps run higher into Class A and offers a subjective listening character that is both linear, yet super smooth, with a wide, two-channel presentation when using the best speakers.

  I played the Warren Bernhardt jazz SACD So Real that I usually audition with new gear. And I immediately noticed the clarity and space in the drum cymbals and piano. The dimensional room reverb cues and that brush-to-metal cymbal tone was very real indeed. But the mostly Class-A delivered sound never had an edge, which made the music that much more listenable.
  The other thing I noticed was how neutral the INT-60 is. It is musical in the sense that we are listening to music delivered as it was played and recorded, but the lack of artificial color made my ears quite happy. This integrated has nearly perfect balance of listening ease and accuracy. I would challenge you to find separates in this range (or more) that deliver sonic faithfulness.
  Okay, so it sounded great with electrostatics that have a powered subwoofer, how did it fair with passive speakers? The PSB T3 towers, one of my favorite bargain audiophile speakers, offered a terrific blend of treble extension, smooth midrange and nice tight, extended bottom end. With the amp now driving a full-range speaker, the bass delivery of the modestly powered, INT-60 was clean and quick through the PSB’s.
  I confirmed the Pass’ bass capability with my review pair of Westlake Towers 5’s as well. The midbass is a little leaner on the Westlake than the PSB’s, which made it sound even quicker. The INT-60 amp is not some overly warmed MOSFET circuit; it is really clean! Classical guitar picked notes, drum cymbal brushes and upper-piano notes rang with accuracy without any edge.
  Switching to another Classical SACD, I played the RCA Living Stereo of Berlioz — Symphony Fantastique from 1958, great dynamics from analog tape, and recorded in a superb venue. The PSB T3s relayed all the Pass-powered intensity that I am used to hearing from this recording, but nary any hardness. Though 60 watts does not seem like much power. It is plenty. Likely only the hardest-to-drive speakers would give the Pass INT-60 any problem.

Pass remotes still made of metal, exuding that classy feel...

  On Pop Music, I popped into the Oppo the 2015 remix of YesFragile, done by Steve Wilson. The Hi-Res files are on Blu-ray. The long album cut “Roudabout” sounded really good with a wide spread of the acoustic/classical guitar intro, and then clearly separate drum, guitars and keyboards. A fairly complex recording for its time, it really holds up in Hi-Res. Another track that showcases the reissue is “Heart of A Sunrise,” which has really good vocals by Jon Anderson centered nicely with the Pass INT-60 powering the Westlake Tower 5s. This amp can do no wrong.
  As good an amp as the INT-60 is in keeping the congestion out of complicated, multitrack music, I really dug its ability to convey the minimalist  acoustic tracks and solo music I was listening to. On the MartinLogan Impressions, the system sounded so good on the Gene BertonciniBody and Soul SACD, which is one of my favorite nylon string solo recordings. Mr. Bertoncini’s version of “Greensleeves” has this enveloping acoustic image that just spreads across the room, courtesy of the INT-60 and the ML’s. And it is clean and warm, just as a nylon string guitar should be.

A serious choice for LPs
  I played a bunch of vinyl with the budget VPI Player belt-drive turntable, equipped with a Hana “E” series MC high-output cartridge. I bypassed the onboard VPI phono pre, and used the excellent phono pre section of the Rogue RP-5 preamp. On my limited edition, 45 RPM West MontgomeryFull House LP set, the sound was clean and well defined across the image, and delivered that live percussive character the recording is known for. Guitar, piano, sax, bass and drums sounds are relayed via the Pass with the audiophile's original energy intact. Me thinks the INT-60 can do no wrong.


  Ditto on the Three Blind Mice reissue of the 1970s Jazz audiophile classic Isao Suzuki TrioBlow Up. I paired the Pass with the tube phono pre stage of the Rogue RP-5 tube preamp to play this classic reissue; the LP sound was just about as clean as the SACD version from the same tape, and the Pass kept the percussion from becoming too course, as it is some places.
 Whie we are on the subject of vinyl, I would like to see the INT-60 have a built-in phono pre for those who decide that 60 watts is plenty for their vinyl playback system. Using an outboard phono pre shows that it is quite capable with vinyl. Maybe Pass could add one as an option, and keep the cost under $10,000
  Overall, the Pass INT-60 worked perfectly as far as function and ergonomics. The remote reliably switched between sources, and I love the tactile feel of that big, on-board, volume control. Although it got plenty warm, it never got too hot to touch.
  I did use the balanced outputs to drive another amp during the review, a hybrid Rogue Audio Class D/tube Medusa (200 wpc). The combination of the .8 preamp and the Rogue’s precision also reinforced what I heard with the integrated’s internal pre/amp collaboration: the no-nonsense character of the preamp complements what ever good amp you are using. The Pass/Rogue pair sounded great as I expected they would. You can also use the variable XLR and RCA outputs to drive powered subwoofers if you desire a system of speaker separates.
  One other pairing that I did included the INT-60 and a pair of made-in-Finland, Amphion Argon3S stand speakers. I bet a lot of Pass customers will buy the INT-60 to pair with space-saving, stand speakers, like the Amphion's; the integrated worked wonderfully with the Argon3S  two-ways, which are very analytical and have a clean bass character that is not pumped in the midbass. 
For those who desire more power in this design, Pass Labs also offers the 250 wpc INT-250, which is essentially the same design with four times the power. It is priced at $11,000, and is said to be able to drive even the most difficult-to-drive speakers.

The verdict
  The INT-60, indeed, is one of the best sounding integrated preamp/amplifiers I have ever reviewed. It is tough to better the INT-60 with separates in this price range. Even if you spend a bit more, you probably will not top it. Incredible detail, width and depth in the expansive stereo image, plus quick bass response makes it ideal for those who want to explore the best in Hi-Res, or their CD collection. Or hook up your favorite phono preamp (the only thing missing from this fine package) and you got a dandy vinyl playback system.


  Although separates often attract the audiophile’s attention, 99 percent of us HQ-audio listeners would be happy with the simplicity, economy and, in this case, great sonic attributes, of an integrated. And look at all the space you save.
  The list of my INT-60 accolades concludes with an Everything Audio Network Stellar Sound Award, and a nomination to our EAN Integrated Amplifier of The Year category.

 John Gatski has been evaluating consumer, audiophile, home cinema and professional audio gear since 1988. In 1995, he created Pro Audio Review, and he has written for SoundOnSound, Audio, Laserviews, Enjoy The Music, The Audiophile Voice, High Performance Review, Radio World and TV Technology. Everything Audio Network is based in Kensington, Md. Articles on this site are the copyright of the ©Everything Audio Network. Any unauthorized use, via print or Internet, without written permission is prohibited. John Gatski can be reached via email: everything.audio@verizon.net


Wednesday, November 1, 2017

Audiophile Review!
Rogue Audio RH-5 Headphone Amp:
With Line Stage, Phono Preamp Option,
“Top-Tier Path For Serious HP Listeners”

Brevis...
Price: $2,495
Likes: clean detailed HP path with line pre
Dislikes: like it all, but please add a DAC
Wow Factor: a must-audition for HP fans
More info: Rogue Audio RH-5

by John Gatski
  I have owned numerous Rogue Audio products since 1998, and currently run a RP-5 as my reference tube preamp and a Medusa as my Class-D amplifier. Rogue makes all kinds of tube components, and a few preamps with a headphone circuit, but the company never has made a focused separate headphone amp — until now.
  Rogue Audio President, Founder and Chief Designer Mark O’Brien have remedied the standalone HP amp omission with the new RH-5, a dandy, full-featured headphone amp/line-stage preamp that exemplifies a state-of-the-art tube /solid state design that gives you a low-noise, and hi-res playback finesse — without the excessive color of many HP amps.
  Priced at $2,495, the RH-5 is a HP amp with several unique design aspects that O’Brien has implemented to get the best out of good-sounding headphones.
  “Because the requirements for a headphone amp are very different than for typical stereo preamps or power amps the RH-5 is a unique design that is quite different from any of the other gear we make,” said O'Brien. “I wanted it to be a tube design but creating a tube-based headphone amplifier has some very unique challenges."

  Rogue Audio has  taken the traditional HP amp circuit applied a bit of custom, hybrid circuit magic, and netted a fantastic-sounding, HP listening path that you would not believe is tube; it is that quiet!

  He explained: “the basic circuit uses a pair of Russian-manufactured, low-noise 12AU7tubes in a mu-follower circuit configuration, followed by high-power MOSFET buffers. Pretty much all of the voltage amplification is done in the tube domain, while the buffers provide the current to drive the most difficult headphone loads.”
  O’Brien said the hybrid design approach offers the best of solid state and tube in terms of  its sonic attributes. “I really like this circuit because it offers the great sound of tubes, yet is super quiet and very powerful.” O’Brien noted.
  Besides the sophisticated, modern, hybrid design approach, the RH-5 also utilizes Rogue’s RP-X technology platform, which is a DSP engine that offers more modern control of the gain, more efficient and quieter switching as well as a host of connection options. I love that 30 second countdown upon start up as the circuit stabilizes.



Features
  The RH-5 connection cadre includes three pairs of RCA inputs and one pair of balanced XLR inputs. Headphone outputs are provided via fully balanced, 3-pin and 4-pin, fully balanced outputs, as well as two 1/4-inch TRS headphone jacks . The extra 1/4-inch jacks enables the two-listener option, such as in a pro audio tracking/mixing room and for audiophiles who like to test different headphones via a really good HP amp.

Not only is it a HP amp, but it is a full-festured line preamp

  Three gain settings allow the output to be matched for either high, medium or low-sensitivity headphones. An easy-to-read OLED display elegantly communicates component settings and volume. The display can also be turned off, if desired, for those who like the dark side of HP listening. The included remote allows you to turn on the RH-5, change volume, select source, mute output and dim the display.
  The RH-5 is not just a superb headphone amplifier, it can also be used as a line preamp with balanced and single-ended preamplifier outputs. And if all that is not enough, an optional phono board enables quality, vinyl playback through either the HPs, or line out to an amp and speakers.

 “Because the requirements for a headphone amp are very different than for typical stereo preamps or power amps the RH-5 is a unique design that is quite different from any of the other gear we make.”
Mark O'Brien
President, Rogue Audio

  The onboard MM/MC phono pre offers user-adjustable gain settings of 43 and 58 dB to accommodate most cartridges. A wide variety of loading options also means your favorite cartridge can be configured to sound its very best.
  Although there are numerous HP amp/DAC combos on the market at various price ranges. Rogue Audio did not go down that road (this time). However, this hybrid RH-5 design is so impressive, I bet if they did design a HP/amp DAC, it would be a killer. After all, Mr. O’Brien knows a thing or two about digital products. His digital/tube hybrid amps are top class in their respective niches.
  For the RH-5, however, O’Brien simply stated: “Most people using this level of headphone amp would prefer to use their own dedicated digital gear.”

 Rogue Audio RH-5 Specs:
- Tube complement: 2 x 12AU7/ECC82 tubes;
- Frequency response: 5Hz – 50 kHz +/- 1 dB;
- THD: <0 .05="" font="">
- Gain line stage: 3dB/12dB/16dB (selectable;)
- Rated output: 3.5W (32Ω);
- Output impedance: <0 .1="" font="" khz="">
- Gain phono stage: 43 dB, 58 dB;
- RIAA accuracy: +/- 0.1 dB;
- Phono overload: 40mV;
- Power consumption (On): 31W;
- Dimensions: 15”W X 13.5 ”D X 4” H;
- Weight 19 pounds.

The set up
  I installed the RH-5 into my audiophile system for the review, feeding it with several DACS and then driving several headphones over a two-week period of serious listening. The HPs included a pair of Sennheiser HD-650, Shure SRH-1840 and AKG K702/K812, and Oppo PM-1 planar magnetic.
  I also used the RH-5 as line-stage preamp with the various DACS as sources, including Benchmark DAC3-HGC, Oppo Sonica, Prism Callia and Mytek Manhattan II. For comparison purposes, I had on hand a Rogue Audio RP-5 line preamp.
  All speaker listening was done via MartinLogan Impression. Cabling was courtesy of Wireworld Cable. The AC cables and distribution were provided by Essential Sound Products. Since Rogue Audio burns in all their products before they ever hit a dealer (or reviewer), I hooked up the RH-5, let it stabilize for 10 minutes and began my listening.

The audition
  First up, I played the Everything Audio Network reference track I always start most listening sessions with: Warren Bernhardt "So Real," the ripped DSD tracks  from the DMP SACD of the same name.
  This live-to-two-track direct DSD recording from the early 2000s was recorded by Tom Jung, and the stereo is simply awe-inducing with a great HP (or speaker system). Percussion sounds, such as cymbal brushes and snare rim shots are incredibly real sounding, as is the warmth of the bass and the precision resolution of the Steinway grand piano.
  The Rogue Audio showcased the “So Real” track with that wonderful, wide spacing of the instruments, and it is oh-so quiet for a tube HP amp. If you are a listener of traditional tube circuits, you would swear the RH-5 is all solid state.
  The RH-5 also passed the upper-register piano textures of the Steinway piano with that unique tinkle and slight reverb decay that the better audio products are capable of delivering with this track. Lesser headphone amps seem to muss up that bit of room reverb projection in that track — with their narrower soundstages.

Good design, good parts = great sound!

  I auditioned Gene BertonciniBody and Soul, an album with a slew of jazz standards played on a nylon-string guitar, exquisitely mic’d in stereo and recorded straight to DSD. Again, the RH-5 revealed the wide spacing of the stereo recording setup, and fully fleshed out nylon string note runs as played by Mr. Bertoncini. The tube microphone warmth embodied in the recording was intact, but not over-bloomed.
  Sticking with the acoustic guitar theme, I played the recent reissue of the YesFragile, the latest Steve Wilson mix at 24/96 on Blu-ray, using a Oppo UDP-205. Guitarist Steve Howe’s “Mood For A Day” acoustic guitar masterpiece. The RH-5 really nails the track, showcasing Steve Howe’s  dynamic pick attack, a very full, defined stereo image and that subtle warmth often lacking in  today’s Rock solo acoustic guitar recordings that use inferior, internal guitar pickups.

Yes - Fragile remix/remaster sounded great via Rogue RH-5

  Moving on to Classical music, I played Joshua Bell’s Tchaikovsky in D Violin Concerto DSD recording on SACD, via the Oppo 205. Listening through my AKG K702 Anniversary HPs, I wanted to hear whether the Rogue could relay the vibrant, but not harsh, violin texture of Bell’s instrument. Sometimes HPs and HP amps combine to add an over stridency to the violin, the delicate balance of high-frequency, wood/string/bow energy becomes hard edged. It always gets blamed on the digital, but it is not always the case. The HP amp can exacerbate stridency.


  Again, the RH-5 revealed the wide spacing of the stereo recording setup, and fully fleshed out nylon string note runs as played by Mr. Bertoncini. The tube microphone warmth embodied in the recording was intact, but not over-bloomed.

  The Rogue Audio RH-5 added not one bit of extra edge to the violin recordings. The AKG’s sounded as smooth with the Tchaikovsky as I have heard it through headphones. I noted the same transparency when playing several Heifetz, Midori  and Hillary Hahn violin recordings.
  Classical lovers who are headphone users will also love the RH-5 on symphonic music. I recently purchased the RCA Red Seal “Living Stereo: reissue of the 1950s BerliozSymphony Fantastique, and fell in love with this version: incredible analog smoothness with great dynamic power when the orchestra goes full force, especially in the fifth movement.
  On my Oppo PM-1 planar magnetic headphones, which I ran balanced from the Rogue’s balanced HP output circuit, the Berlioz Symphony was indeed fantastic.!Such smooth, yet powerful brass and strings. Hard to believe it was recorded 60+ years ago. The dynamic range of the fifth movement is such that you have to turn it down when it reaches the crescendo.

Its only Rock N‘ Roll
  On Rock/Pop music, such as the Yes reissue and numerous, other well-recorded albums, the RP-5 is very good at resolving the complex path of multitrack mixes and transmitting listenable audio directly to the ears. Daft Punk’s "Get Lucky,' with that funky Nile Rogers rhythm guitar and disco drum beat, came through with ample air around instruments and a warm, kick drum presentation.

  On Gene Bertoncini — Body and Soul, an album with a slew of jazz standards played on a nylon-string guitar, exquisitely mic’d in stereo and recorded straight to DSD, the RH-5 revealed the wide spacing of the stereo recording setup, and fully fleshed out nylon string note runs. 

  My Led Zeppelin and Nirvana hi-res downloads got the royal treatment from the Shure SRH-1840 open ‘phones and the RH-5. Its smooth, low-noise persona showed that the midrange-heavy overdriven style of Rock did not get overly charged by the playback electronics and HP drive. That separates the men from the boys when it comes to good HP design.
The line stage
  Since the RH-5 is billed as HP amp, by golly that is how I used it — mostly. But since it offers a fully featured line stage (as well as the optional phono stage, which I did not have installed), I played everything that was monitored by headphones through the line-out to the Pass amp/ML speakers.
  Sonically, the line stage is a great bang-for-the-buck, balanced and unbalanced audio pathway for those who who like to use their HP amp and line preamps in one box. However, the RH-5’s line stage is not as revealing as the Rogue Audio RP-5, which has more of that tube richness and image openness, while the RH-5 sounds more solid state. Mr. O’Brien terms the RH-5 as “a great headphone amp with a good, entry level, line stage.” I agree.


  I had not one single complaint about the RH-5, through the 100 hours or so of listening over several months, it had no problems. No tube noise, and the remote worked perfectly — even when I aimed it off center of the IR receiver on the front face plate.
  As with the RP1 and RP-5, I love the 30 second countdown as the tubes warm up, The RP-X switching and control engine is a major step up over conventional analog controls, routing and switching, and it gives the Rogue a much higher-end feel and operation precision.

The verdict
  Rogue Audio has  taken the traditional HP amp circuit applied a bit of custom, hybrid circuit magic, and netted a fantastic-sounding, HP listening path that you would not believe is tube; it is that quiet.
  Couple the great sound with its massive drive capability, full array of connection options and a top-tier line stage (plus an optional phono stage), the RH-5 is all that most HP-focused audiophiles will ever need. I nuzzled up to it, immediately, with my Austria-manufactured AKGs and never looked back. I guess I liked it. Stellar Sound Award? You betcha!
  By the way, I believe that a HP circuit this good should have a digital converter attached to it. I would like to see a version of the RH-5 with a built-in DAC. Are you listening, Mr. O’Brien?

 John Gatski has been evaluating consumer, audiophile, home cinema and professional audio gear since 1988. In 1995, he created Pro Audio Review, and he has written for Audio, Laserviews, Enjoy The Music, The Audiophile Voice, High Performance Review, Radio World and TV Technology. Everything Audio Network is based in Kensington, Md. Articles on this site are the copyright of the ©Everything Audio Network. Any unauthorized use, via print or Internet, without written permission is prohibited. John Gatski can be reached via email: everything.audio@verizon.net