December 2019

World Premiere Review!
Raven Audio Osprey MK3 Vacuum Tube Integrated Amplifier
Fanatic attention to every detail.
Review By Ron Nagle

  Once upon a midnight dreary, while I pounded, weak and weary, with a tap, tap, tapping on a darkened Qwerty. Now with many a quaint and curious tome proffered, still, I must type evenmore. The Raven Audio people are a Texas based company. Raven's products are made in the town of College Station, Texas. They are a manufacturer sharing some manufacturing facilities with the aerospace industry. And the aerospace people manufacture some things that are classified as, "only on a need to know basis."

This evaluation concerns the newest upgraded version of the latest Osprey Integrated Amplifier, the Mark 3. The Osprey MK3 manufacturer's suggested retail price is $4895. It occupies the top of the Raven Audio's Avian series. This series is comprised of three hollow state amplifiers. Following the Osprey MK3 is a less expensive Blackhawk Integrated at $3795 and last at number three in the line is the $2995 Nighthawk MK3 integrated.

The founder of Raven Audio, Mr. Dave Thomson as he's the tube Docent, has a broad knowledge of vacuum tubes, especially rare vacuum tubes and he has amassed a formidable collection. Fairly recently Raven Audio has expanded their line of audio products too include audio cables and two floor speakers. One of these the larger Corvus speaker comes with built in bass amplifiers and sells with an introductory price of $12,995. And following that is the smaller Celest speakers with the introductory price of $3995. Ravenrecently added a line of high quality SONIQUIL branded power, speaker and interconnect cables.

Note: There were many sample cables that came packed with the Osprey amplifier. I assume that the Raven guys want me to try them out.

Raven Audio Osprey Technical Details
Physically speaking my Avian Series Raven Amp has a very classy looking high gloss pearlized metallic black baked ceramic powder coat finish. This is in contrast with a silver matte finished anodized aluminum front panel. This same silver treatment extends to a top trim plate and the thick silver handles (I love) on either side of the Amplifier. I weighed the amplifier with all ten tubes in place, it was 31.8 pounds. Side to side it measures 15.375" at the front panel, 13" deep and 7" high. The Raven tube complement consists of four matched beam power 7581A tubes.

Additionally, there's two each 12AT7 for the preamplifier stage, 12AT7 for the power amp first stage, and two 12AU7 for phase inverter / driver. The power tubes were unfamiliar to me I had to look up the 7581A tube. The suggested match was a 6L6 Beam Power tube. However this is not just any old 6L6GC replacement mind you. The 7581A is an upgraded version of the Tung-Sol 7581. It offers an impressive amount of clean headroom and boasts a plate dissipation rating of 35 Watts.

The front panel has three matching control knobs, left to right they are. A two position on/off switch, next at the center, a Volume control and last a five-position source select switch. Commendably, turning the Osprey on or off never produced any nasty sound from my speakers, that function was totally silent.

Around the back at the amplifiers input side you will see six pairs of incredible quality female RCA jacks. These gold plated jacks are serious heavy duty hardware, and I have never seen the like before. They are bolted onto the rear panel, I had to force one set of RCA plugs forward to attach the cables. Compare this to mass market components with board mounted RCA plugs sticking through holes drilled in the back panel. I wish all RCA connections were made like this.

The innermost number 6 pair of RCA jacks is near the center of the rear panel and serves the special purpose of a dedicated SUB OUTPUT. Now directly in the center next to that is a control knob for a high pass crossover. With it you can select three options for your subwoofer signal, they are Bypass, 80 Hz, or 100Hz. Also you will find six plastic insulated European style speaker cable connectors. There are three for the left channel marked "0, 4, 8 Ohms" and there are the very same designations marked for the three right channel connections. Last but not least is the IEC socket for the AC power line and a five Ampere fuse.

State Of Who's Art?
Log on and you can shop the electronics supermarket with your computer. There you will find a broad selection of printed circuit boards that are already stuffed with components. And to power that you could buy a digital power supply. As a matter of fact to power most anything you need only select a digital power supply directly from a manufactures catalog. But using this process something very valuable gets lost. The point I'm trying to make is that the birth a stereo amplifier needs to be a trial and error creative process. Someone who cares will proceed as if they were tuning a piano, stopping to listen at each step in the process.

It seems to me what is left of this fanatic attention to detail still resides with our hot bottle brethren. Granted, it is never good to generalize. However I did find actual supporting evidence when I unpacked the Raven Audio Osprey Integrated Amplifier. The Teflon wired hand build quality is absolutely first rate. Every vacuum tube that came with this amplifier was specifically chosen and place marked as to its' location. In addition I was given twice as many tubes as was necessary. Some of these are rare and some are expensive. Tube swapping referred to as tube rolling would enable me to alter the sound of my system and to a smaller degree change the stereo image. To use an analogy; like the astronomers' telescope, our music systems are time machines. Though them we can look back and evoke a pleasant memory from the past.

Here To Testify For You
How do you describe what you hear as real? The answer is with great difficulty it seems. There is a myriad of very small things that must be present, and all of it must be contained in a natural balance. Let me use my own PrimaLuna Prologue Integrated amplifier as a comparison. I have owned the Prologue for several years and I know it's sound intimately. It is an early version, one of the first in the PrimaLuna line. Still, it makes a rather fair comparison to the Osprey review subject. There are similarities; The PrimaLuna is powered by four matched KT88 tubes churning out 33 Watts per channel. The Raven Osprey is rated at 30 Watts per channel and is powered by four matched 7581A tubes. During the time I had it I never thought that the sound of my Prologue was in anyway lacking with the possible exception of some low bass drive. But I am not into seismic bass so I never thought that it was important. My Prologue Amplifier has a nice Tube'y top to bottom voice that seems real and natural.

Yet compared to what I'm experiencing now with the Osprey MK3 in my system. I can hear most of the same top to bottom tube generated even order harmonic tonal retrieval. But now you can add to that much better definition. [Read: detail retrieval.] The overall effect is a deeper stereo sound stage. Small details that were buried and overridden appear now in a more dimensional sound field. Let me refer to a Diana Krall CD and it is her very first debut album. Stepping Out [Justin Time, Just 50-2] is from Montreal Canada, with my favorite track being "Do Nothing Till You Hear From Me". She forms the third part of a trio. And accompanying Ms. Krall on piano is Jeff Hamilton on Drums and John Clayton on String Bass.

With the Osprey pushing notes there is an unexpected reality that moves forward and sits in my lap. Clayton's bass conveys a crystal clear bass line. That gets resolved to the sound of his finger friction stroking those fiddle strings. Clayton's bass is the sound of a warm wooden chamber that projects and propels the music into my room. When the lights in my room are turned down low, Ms. Krall words and phrasing are intimate and real as she sings just for me.

Black Disk
Under my arm I carry two records that I won at an Audio Society ticket drawing. Was I supposed to refuse free music? One of the recordings is The Sony Clark Trio. Very hard to find and very high quality, but not a recording that I would have selected. For me my insight into the meaning and emotional message in music is contained in the human voice. The recording is The 1960 Time Recording Sessions with George Duvivier on Bass and Max Roach on drums. Before I get any further, I need tell you my reference Phono amplifier is my six tube Tavish Adagio.

I'm repeating myself when I tell you I believe hollow state tube amplifiers and vinyl recordings seem to have an affinity to each other. Listening to the Sonny Clark track, Nica (Take2) the recording is very revealing but in a disappointing way. The start of this recording is mic'ed very close to Max Roach's drum kit in the right side speaker. So much so that the swirling metallic brush work on the drum surface partially obscures Sonny Clark on piano. Additionally the string bass fiddle is pushed back in the mix and almost not part of this track. Color me very surprised that this particular microphone setup made it to vinyl LP. I can only think it appeals to people who play drums. Crystal clean and clear but you can't get much melody out of a drum head. Lesson learned, you get exactly what is in the grooves, nothing added and nothing held back. As a review subject, the opening track and the entire recording shows the impeccable resolving power of the Osprey Amplifier.

Moving On
Many recordings and many hours can be summarized by describing this first track from Sting's vinyl album, The Dream of The Blue Turtles song "If You Love Somebody Set Them Free" [AM+CD 2750]. This is perhaps the least compressed vinyl recording that I own. The track is replete with tons of studio reverb featuring a prominent repeating bass. The reverberation may be artificial but it is full of micro dynamic details that locate and separate all of the players onto a wide and deep soundstage. Nothing is held back the bass line is reproduced as a deep driving force. It is a repeating low frequency tempo that compels you to become involved. It serves as a perfect example of large and powerful dynamic contrasts.

My Piece De Resistance
At the just ended New York Audio Show 2019 I purchased from Chad Kassem of Acoustic Sounds a copy of a Nils Lofgren album, Acoustic Live [APP 090]. This is a two record vinyl reissue. The CD/DSD version has been one of my go to reference recordings for quite some time. Spinning the Vinyl version is a better musical experience. The most noticeable difference between vinyl and the CD version is the sound stage. There is just more information in the form of Micro dynamic contrasts. Buried in the grooves of this audiophile quality recording there exists even greater details revealing the layering of the elements that make the performance. The most prominent area on this Black Vinyl disk is in the lower midrange. You can't call the string guitar accompaniment deep bass but as the lowest instrumental part of this track it serves as the emotional underpinning of the performance.

My favorite song on this record is Some Must Dream. Now as you listen you can hear the subtly present live sounds of the surrounding venue. That space is in fact a complex mix of many small whispers of sound. For me a large portion of this quality is described by the word "continuousness" that is a term coined by the late Harry Pearson. It used in part to describe an organic live presence that exists as you listen to a complex cord that slowly decays into silence. I would like to remind you of a problem inherent with Red Book CD digital encoding. As the intensity / volume of a sound fades it is treated as a least significant bit and dropped. The major difference between this recording and the same DSD versus CD version is that the entire body of sound retains a natural and complete range of frequencies both odd and even. With an analog recording those overtones decay into silence naturally, just as it is in life.

My Deposition
At home my music system has never sounded better. I have invited friends over to listen and they commented that it sounds, real. The effect they described was "as if the performers were actually in the room" with them. I went on to explain that's audio's Holy Grail, that's why some people spend tens of thousands of dollars. It's all because of their love of music. It is not enough for some of us to just sit and listen. But far better to suspend disbelief and immerse your senses, than to become part of the performance. Why do I write about audio? It is because on rare occasions I just might experience music with a deeper understanding and with a greater emotional involvement.

For a brief time that's the gift the Osprey has given me. In my 30 year long pursuit to bring music into my home, this is the best of times. The Raven Osprey and specifically the Mark 3 version is built like a tank to last for decades. At $4895 the amplifier is not cheap. But if you see it and hear it you can appreciate for yourself where the money went. No expense was spared in its design and construction. If you can afford it then don't deny yourself, go and audition, you won't regret it. You will have a 45 day home trial to make up your mind or if you might opt to return it. The Raven Osprey amplifier paints a better musical reality then anything I presently own.

Remember to enjoy the music! And from me, Semper Hi-Fi.

Footnote: Regarding the mix of audio cables that was sent with the Osprey Amplifier…. I can only comment that I probably own the worst audio test bed to audition cables. Over the last 30 years I have accumulated a Hoge Poge mixture of every kind of audio cabling, they are a conglomerate of Good, Bad, and Indifferent. The back of my audio rack looks like a spider's web. To do a meaningful evaluation you should do a complete rewire of a system that you know very intimately and all with the same brand of comparatively priced cables. All things considered, I do not own that system. To be fair, I can see the cable fabrication is of a very high quality and the plug termination on all the wiring is first rate. As a matter of fact the banana plugs have a spring contact feature that I have never seen before.

Reference System
Sources:
SOTA Nova Turn Table, Grado Laboratory Standard Tone Arm, Denon DL-301 II Cartridge.
Sony UHP-U1 Universal digital disc player. Music Hall upsampling DAC 25.3 with headphone amplifier, and Yamaha WXC-5 Wi-Fi Bluetooth receiver.

Reference Amplification:
Sanders ESL power Amplifier and Prima Luna Prologue Integrated Amplifier.

Speakers:
Aurum Cantus V30M, with Mark Daniels Omni Harmonizer tweeters.

Speaker Cables:
Kimber Kable 12TC @ 11ft. And a Kimber Kable 8TC 18" to tweeter speaker.
Interconnect Cables: Monster Reference four pairs, two 0.5 meter, 1 meter and 1.5 meter, Nordost Red Dawn, Music Hall1 meter Phono cable, Audioquest Cinnamon XLR 1 meter,
Chord Silver Siren 1 meter, Homemade Teflon RCA 1 meter, Autobahn 0.5 meter digital

Power Conditioning:
Wire World 10 gauge IEC line cord, Power Cords: Kaplan Cables 12 gauge IEC
Islatrol Industrial 20 Ampere ac line conditioner, Richard Gray 20 Ampere Sub Station
Alpha Core Balanced Transformer Power Supply, and Audio Power PE-1 power enhancer.

Specifications
Type: Vacuum tube stereo integrated amplifier
Output: 30 Watts per channel, two channels
Frequency Response: 20Hz to 20kHz
Tube Complement:
    Two 12AT7 - Preamplifier stage
    Two 12AT7 - Power amplifier first stage
    Two 12AU7 - Phase inverter/driver
    Four 6L6GC - Power tubes
Auto-biasing (typically no need for adjustment, yet can be for vintage tubes)
Speaker Terminals: 4 and 8 Ohm
Inputs: Six unbalanced RCA
Recommended Speaker Sensitivity: 85dB+
Dimensions: 15.5" x 14" x 6.5" (WxDxH)
Weight: 35 lbs.
Price: $4895 on up depending on tube configuration.

Company Information
Raven Audio
6840 W. 70th Street
Shreveport, LA 71129

Texas Office
135 Old Groveton Road South
Onalaska, TX 77360

Voice: (318) 703.4542
E-mail: info@ravenaudio.com 
Website: www.RavenAudio.com