Date: 2024-11-25

Germany-based Octave Audio's origins date to 1968 when it began as a transformer-winding factory called Hofmann, after founder Karl Heinz Hofmann. In 1975, Hofmann's son Andreas, an audio enthusiast with "electric current in his blood," to quote the company website, introduced hi-fi into the family business by building and selling his own amps, initially under the Hofmann name. Then, in 1980, the company rebadged his wares with the Octave logo. Not until 2000, when Andreas took over the company, was the Hofmann brand changed to Octave Audio. Today, the company builds transformers for OEM companies, though only a few.

Octave Audio released the class-AB, 70Wpc, push-pull V 70 integrated amplifier in 2003. It has been a constant staple of the company's product line and remains so today—only now it has a brother, the 50Wpc V 70 Class A, released officially in May 2020, though the launch stretched into 2022 due to the COVID pandemic. It's the company's third class-A design, after the 8Wpc V16 headphone/integrated amplifier (2017) and the Jubilee 300 B monoblock (2019). As a fan of the sound of class-A, and an enthusiastic owner of a solid state class-A amplifier (footnote 1), I was excited to review the new model.

I was also a little perplexed because this class-A was different—a push-pull design built on a pentode circuit Hofmann developed to surmount what he considers class-A's inherent liabilities: low power, limited dynamic range, and energy-sucking inefficiency. He dubbed this new design Dynamic Bias Control, a souped-up class-A technology with the potential to deliver 50Wpc—and up to 70Wpc when paired with the company's optional Super Black Box Capacitance Power Storage ($3500 each), a power supply–looking device connected to the back of the V 70 that's said to increase the amplifier's capacitance tenfold to improve current delivery and, hence, the ability to drive difficult speaker loads. Octave says it "stabilizes current delivery and reduces the impedance interaction between amplifier and speaker." Better synergy.

Among the V 70's technical features are a 20–30 second "soft start" delay that turns the V 70 on in stages to protect tubes and other critical parts (but especially tubes) from the inrush of high current that can lead to premature wear; an ECOmode that automatically switches on to shut off the amp's tube section after about 7 minutes of detecting no music signal; a home-cinema bypass circuit; a pre-out for connecting to a subwoofer; and an autobias circuit that shows the stages of a tube's lifespan via a multicolored LED layout: yellow for warm-up, green for biased and ready to go, red for kaput.

In the event of a kaput, Octave recommends replacing two tubes—the matched pair it's a part of. An even better (though more expensive) option is to replace all four tubes—both channels. Compatible tube types include the 6550, KT88, KT90, KT100, KT120, and KT150.

Initially, the V 70 was sold with the KT120 tube, but Russia's invasion of Ukraine made that tube harder to get, so it has been replaced by the KT88 as standard. You can still purchase the V 70 with the KT120.

John Quick, of Octave importer Dynaudio North America, encouraged me to start my critical listening with the KT120. One JJ ECC83S (12AX7) (ECC83) and two Electro-Harmonix 12AT7 (ECC81) input tubes complete the tube array. Thanks to the V 70's "protection circuits and soft-start electronics"—that's from the manual—the power tubes are estimated to last 3–5 years, while input tubes should last 10 years or more. I was intrigued by Octave's assertion, also in the manual, that some tubes can require up to 300 hours of break-in to sound their best.

Like Octave's other top models, the V 70 comes with a power selector—a two-position sliding switch on the back of the unit that offers two power-output settings: High (50W) and Low (25W), the former intended for use with more powerful tube types such as the KT120 or KT150, the lower with tubes that produce less power, such as the 6550, KT88, KT90, and KT100, to avoid overloading them. However, since the KT88 included with the Octave was the Carbon Plate High Bias version, John suggested I try the KT88s in the 50W position on the basis that, as per his email, "the carbon plating allows it to be reliable when fed a higher bias level, thereby producing more power in the V 70 when used in the High 50W setting. We don't recommend using standard KT88 tubes in this setting." I tried the KT88 in both settings and preferred the more open and dynamic presentation I got with High 50W.

The V 70 comes with a tube cage, but John suggested I remove it during listening because, "even though it's ventilated, a certain amount of acoustic energy can build up inside that little chassis. The cage is there really for safety and import reasons." Besides, the tubed V 70 looks prettier with the top down.

Listening
Desert Lady/Fantasy (CD, Columbia CK 57856) by Toshiko Akiyoshi and her 16-piece Jazz Orchestra, featuring Lew Tabackin. I played three minutes of the first track, then three of the next, the title track. The soundstage was grand: flush with detail, big pictures, and colorful images, except this time, during some parts, its pacing and images seemed to drift more than usual, none of which I had noticed on the Adderley CD, which is a much more sterile-sounding recording than this more harmonically tufted Akiyoshi one...

Tube Rolling
Finally came the moment to AB-test swap the KT120 and KT88 output tubes, and it's at this juncture that the concept of synergy became a theme for this review, because while I expected my tube comparisons to result in a universal winner, that's not what happened. The KT88's generally denser tone, more cut-out imaging, and more realistic timbre suited some recordings particularly well, while with other recordings I preferred the KT120's more panoramic, harmonically developed, bassier, more dramatic presentation. In the end, I chose the KT120s over the KT88s, in part because they sounded a smidge more refined and less grainy than the KT88. That could be because, though I burned them in for 50 or so hours, it might not have been enough.

The wrap
I found the Octave V 70 to be a slightly tweaky component (in view of its several options) that presented music on a grand scale, with vivid colors and shapes and a dynamic momentum that was emotionally engaging. It did a few things that don't often coexist in a single product as well as they did in this one: color, texture, transparency, tonal density, sense of touch, bass heft, and dynamic power. Does that sound like your typical tube amp?

I would say that Andreas achieved what he set out to do: create an amplifier with the soul of a class-A combined with the muscle of high-powered AB. The result is a product like nothing I've heard before, which sounded bigger than life and natural simultaneously. The Octave V 70 had the spirit of cinema vérité in Technicolor. All things considered, I think the $15,900 asking price for the V 70 with the KT120 tubes and the Super Black Box is a pretty good deal.

Basic Model                      V 70 Class A, optional Phono MM or MC
Tube Complement            4 x KT120
Design                              Aluminium silver or Aluminium black
Options                              Phono Input  MC or MM
                                        Black-Box and Super Black Box

SPECIFICATIONS
Output power                    2 x 50 W continuous, 70 W Peak into 4 Ohm
Frequency response           20 Hz - 70 kHz @ 50 W - 1 / -3 dB
Distortion                          0.1% @ 10 W into 4 Ohm
Signal-to-Noise Ratio           - 100 dB / 50 W
Optimal Load Impedance    4 - 16 Ohms
Damping factor                  5 @ 8 Ohms

Connections
Inputs                               5 x Line Level / RCA, 1 x Bypass-Function / RCA
                                        1 x Phono optional / RCA
                                        1 x XLR Input

Outputs                             1 x Rec Out / RCA, Pre-Out adjustable / RCA

Features                            ODT / Octave Dynamic Technologies,
                                        ECO Mode, Power Management

Date: 2024-11-20

Lector Digidrive 與 Digicode 旗艦分體 CD 機

• 經過漫長歲月，結合了厰方應用於設計和物理方面的長久經驗，賦予產品發燒級音響純機械、先進電子設備、發燒級細節和所有相關設施，共冶一爐。
• 足以發揮具潛質的音響系統，那怕是膽是石機、個性不同的音響系統。
• 令人注目是其售價適中，乃成功的另一主因。

聲音

• 充滿音樂氣氛，但絕不偏倚，反之靈巧流暢，具備活力，分析力不俗。
• 究竟如何發揮得更好，就看系統質素及調校手段。

Digidrive TL-3 CD轉盤 (配PSU-DTL供電器)

• 參考級頂置式轉盤
• 高度可靠 CD 機械部分，訊號檢拾力強
• CD 穩定器
• 大型黃銅內部結構
• 一體化鋁製機體
• 巨型有機玻璃實心前面板
• 重量：12.5 kg
• SPDiF（1 RCA和1 BNC direct）- AES/EBU XLR 數碼輸出連接器
• 光纖數碼輸出：Toslink（基本)（可選）
• HAFO ST-II (高質素)（可選）
• 原厰遙控器 (可選顯示開/關）

Digicode S-192 解碼器 (配PSU-DC 192供電器)

• 真平衡設計
• 四枚著名 BB PCM1704K 晶片的 R2R 梯形解碼器
• 輸出電路使用四支 ECC-81/12AT7 真空管
• 所有輸入(包括USB)高達 192 kHz 24 bit
• 配備了字時鐘(取樣時鐘，跟其他設備的時鐘訊號用步)輸入和數碼 SPDIF 輸出
• 5 個數碼輸入
• PSU-DC 192 內置一隻隔離牛，為多隻環牛供應 500VA 電力

Date: 2024-11-19

Exposure returns to its roots with a full-width integrated inspired by the improved circuit design of the recent 5010 monoblock power amps. Does 'old school' still cut it?

Nostalgia doesn't come any better than this: an integrated amplifier that looks like it escaped from the 1980s, all minimalist and line-level and 440mm wide. But Exposure has been around for close to 50 years, so this isn't some exercise in retro from an arriviste brand with cod heritage. Rather, the 3510 is a device for reminding people like me of (hi-fi) life in simpler times.

Bold Step
There are three forthcoming plug-ins – a USB/DSD64-compatible DAC and an MM phono or an MC phono board, but the 3510 can only house one. Both phono modules will offer two sensitivity/gain settings combined with 47 kohm loading for MM and 100, 110, 130, 160, 210, 310 and 470ohm for the MC board. In the spirit of the price category, I reviewed our line-only 3510 with an external sub-£500 phono stage.

Specs-wise, too, the 3510 integrated amplifier could have been plucked from the pages of the 1980 Hi-Fi Yearbook although key areas of the preamp circuit design, and even the choice of power transistors, have witnessed a process of evolution and improvement over the decades. Otherwise Exposure operates under the very sensible 'if it isn't broken, don't fix it' school of engineering. The conservative factory power rating is 110W/8ohm and it provides line inputs labelled Aux/Phono, CD, Aux 2, AV with fixed gain for switchable home theatre bypass, a tape in/out loop and two preamp outs, the latter useful for feeding subs or for connecting other power amplifiers.

All of these are single-ended RCA connections, accompanied by two sets of loudspeaker outputs for which Exposure took a bold step – instead of multi-way binding posts, the 3510 accepts banana plugs only. And, in case you're wondering why an amplifier would offer two sets of speaker outputs, but no A/B speaker selector switch (as was once the fashion), their role here is to simplify bi-wiring.

Its uncluttered front panel contains, from left to right, a push button for power on/off, rotary source selector, a row of LEDs to indicate the chosen source, a sensor for the remote control and a ¼in headphone socket. The supplied remote is a new system commander with buttons for other Exposure components, but here deals with source, volume up/down and mute.

Hot Topic
The installation is self-explanatory for anyone who has ever set up a basic system, which adds to the delicious blast-from-the-past ambience. The lack of phono or DAC modules in our sample made my life even easier, and I immediately set it up with feeds from an SACD player, a CD player, an open-reel deck and a turntable-via-phono-amp. Speakers were all stand-mounted two-way systems, but I couldn't resist a burst of the Wilson Sasha DAWs [HFN Mar '19] to sate my curiosity.

Despite the closed nature of all integrated amplifiers, the 3510 does encourage growth over the years, as its doubled-up pre-out and speaker outputs suggest, while a detachable mains cable also begs for experimentation. These, too, recall the mind-set, zeitgeist and status quo of the early days of Exposure, when cables, bi-wiring and other tweaks were hot topics, and even audiophiles on a tight budget expected an element of flexibility. If I remember correctly, even the market-dominating, £79 NAD 3020 [HFN Jan '80 and Nov '12] offered a preamp output.

Silky Thrills
Switch-on is accompanied by a brief muted period, after which three red LEDs illuminate and tell you the system is operational: one for power on, one for the source indication and the last is on the motorised volume control so you can see its position from the listening seat. When you hit mute, the source and level LEDs are extinguished. As for the headphone output, this mutes the speakers when you insert a ¼in jack, and I'm happy to report that I couldn't find a pair of cans it wouldn't drive with anything less than distinction.

Of late, I have been rediscovering SACD, staggered by the way it narrows the gap between CD and LP, but baffled by its cult status. What Exposure's 3510 delivered with the kind of impact I would expect of a £25k high-end import weighing 50kg was Nilsson's Schmilsson [Mobile Fidelity UDSACD 2219], in its tougher moments. Of course, the aching ballad 'Without You' demanded finesse, which the 3510 exhibits by the bushel, but it was the bass run that opens 'Jump Into The Fire' that made me realise this wasn't 'just another integrated'.

For this track, the bass guitar is the lead instrument with Herbie Flowers in virtuoso mode, dominating the number while the rest of the album is piano-biased. The 3510 reaches down deep, but it pulls off a deft trick: instead of the bass overshadowing all else, the guitars at the extreme ends of the soundstage hover around it, while Nilsson's slightly nasal vocals nestle on top of the big, fat, bottom end.

All the while, there's a coherence and openness that reminded me more of the vinyl offering than CD, while the drum solo towards the track's finish had the kind of atmosphere I expect of a pristine Kodo recording. Then the bass comes in again, and even my diminutive LS3/5As seemed more comfortable with the surfeit of lower octave material than one might imagine. Why is simple, for the 3510 exhibits speaker control like a Sgt Major.

As I wasn't in the mood to wallow solely in wooferland, I cued back to 'Without You', a song so excruciatingly poignant that even Maria Carey's histrionic delivery couldn't butcher it. Nilsson treats it with a tenderness that recalls the great romantics such as Johnny Mathis, the stage set with the most delicate piano trills, along with utterly gorgeous strings and horns.

What the 3510 did to surprise me was to present them with a silkiness I associate more with tubes like EL34s or even 300Bs. The 3510 was emerging as a solid-state amp for those who want but cannot cope with valves. Better still was the sense of majesty that this love song warrants, because it is one of the all-time heartbreakers, up there with the likes of 'In My Life' and 'Waterloo Sunset'.

Into Africa
I was starting to think that, at least in digital terms, using SACD was a cheat because it is so inherently superior to any other pre-recorded digital format I have experienced. Turning next to conventional CDs, I slipped in a disc from a package I detest, 80 vile tracks from Now Yearbook 1983 [Sony/EMI 94398 73352]. It made me thank the heavens that I wasn't a teenager when the charts were dominated by the likes of Spandau Ballet, Wham, Spandau Ballet, Duran Duran, or the tedious Spandau Ballet. Desperate to find even one track that wouldn't render me suicidal, I settled on Toto's 'Africa'.

Why, you might ask, would I even bother with this set if I hate 75% of the content? Simple: if a system is magical, you will listen to anything, as I found myself sitting through open-reel tapes from Mantovani, Percy Faith, and even the soundtrack to Zorba The Greek. If the 3510 could render any of those tracks tolerable, from a period when everything was synthesiser-driven, reeking of artifice and so bright and edgy that one's teeth ached, then it was a champion indeed.

Thumbs Up
Back to Toto, which I actually admire because they are peerless musicians and 'Africa' is a gorgeous, elegiac work. (It was that, or Public Image Ltd, or New Order…) Bang! Straight off I was hearing snap and transient attack, supported by rich bass. I have no idea what instruments are on this track because it is, like the dreck that shares disc space with it, a mix of the real and the electronic.

Regardless, the sound drew me in, a scaled-down facsimile of what was possible from an SACD via £100,000's worth of high-end kit. And it was enough to sell me on the 3510's sheer listenability, its competence having already been demonstrated with the Nilsson SACD. One other track on Now Yearbook 1983, though, couldn't be skipped as it's been a while since I revelled in genuine a cappella.

Five voices in perfect harmony: The Flying Pickets' magnificent 'Only You' was a fave demo track back 40 years ago and it still sends chills up and down my spine. Here the challenge was to see how Exposure's 3510 separated the voices, though I have no idea if this was multi-tracked, tweaked in the studio or otherwise manipulated electronically. Whatever its origins, the performance was opened up sufficiently for me to home in on each voice with remarkable facility, and yet it was always cohesive.

It was the new 45rpm issue of Jeff Beck's immortal Truth [Mobile Fidelity MFSL 2-502] that stamped a solid thumbs-up on this integrated amp. Take my word for it, if you love this album as I do, this is as good as it gets. The 3510 handled every element with skill, from the textures of a then-young Rod Stewart's vocals to the roiling bass courtesy of Ronnie Wood, all the while respecting the thunderous percussion of Micky Waller.

But the star here is Beck, and his specialty is wrenching myriad textures and sounds from his guitars: wah-wah, fuzz, even a lush interpretation of 'Greensleeves'. So a tip for Exposure dealers: demo the 3510 amp with this album, and you'll sell one every time.

Hi-Fi News Verdict
In addition to providing a muchneeded and refreshing wander down Memory Lane, Exposure's 3510 integrated reminded me how much fun an uncomplicated system of source/amp/speakers can be. It worked faultlessly, drove hungry speakers with ease (inc. Wilson's Sasha DAW) and established a case for simplicity – not something every part of the audio biz wants to hear. You want painless hi-fi? You got it.

Technical Specifications
Continuous power (<1% THD, 8/4ohm)           135W / 220W
Dynamic power (<1% THD, 8/4/2/1ohm)         166W / 318W / 546W / 762W
Output impedance (20Hz–20kHz)                    0.010–0.022ohm
Freq. resp. (20Hz–20kHz/100kHz)                   –0.19dB to –1.0dB / –15.8dB
Input sensitivity (for 0dBW/110W)                  25mV / 265mV
A-wtd S/N ratio (re. 0dBW/110W)                   80.2dB / 100.6dB
Distortion (20Hz-20kHz, 1W/10W)                   0.003–0.058% / 0.006–0.051%
Power consumption (idle/rated o/p)                 25W / 370W (1W standby)
Dimensions (WHD) / Weight                           440x115x300mm / 12kg

Date: 2024-11-15

多年來 Siltech 的旗艦音響線材一直都是 Royal Triple Crown「三皇冠」，它不僅是品牌最好的線材，也可稱得上是全球最好的線材。2015 年面世的 Triple Crown 至今已超過 8 年， 是時候推出比 Triple Crown 更好的產品了。其實 Siltech 早於 4 年前已立項新一代旗艦線材的研發，由於 Triple Crown 的性能已相當完美，要想再次突破實屬不易。經歷無數次的試驗和失敗，終於在技術上取得突破，成功研發出最新一代旗艦 Master Crown 系列。

Master Crown採用的是Siltech更新的 S10+單結晶純銀導體，以最佳比例混入單結晶純金，而架構導體的絕緣和隔離材料高達11層之多，例如；Kapton聚酰亞胺薄膜、Kapton、真絲、鐵氟龍、獨家絕緣材料，藉此讓不同材料彼此揚長補短，就不會有單一材料的癖性而造成聲音不均衡。Siltech篤信用最好的材料及足夠好的線結構才能設計出最好的線材，僅有一兩層材料的單一導體線材是不可能像Siltech線材這樣好聽。

Siltech覺得自己的 Triple Crown已是完美很難超越，要發出比 Triple Crown 更好的線材所遇到的困難可想而知。在這種樣樣都完美的情況下，僅在冶金技術上是無法再有重大突破，於是改變了舊有的思路，一切回歸音樂本源，通過研究不同類型與不同等級的真實樂器，然後用最新研發的軟體來分析在高等級樂器聲音的關鍵差別數據。這做法顯然超越了傳統儀器所能達到的結果，通過非常細微的聲音差別研究所得到的數據用於線材設計，才有了新一代旗艦 Master Crown 的全面突破。Master Crown的導體用量比Triple Crown多出最少有1.5~3倍，在絕緣方面使用了5種不同材料 (Kapton聚酰亞胺薄膜、Kapton、真絲、鐵氟龍、獨家絕緣材料) 才達到了聲音全頻穩定、均衡、低失真、無音染的更高目標。

Master Crown 平衡訊號線運用了首創的新技術，讓噪訊和失真達到歷史最低水平。此平衡訊號線具有特殊的結構和屏蔽，可以讓正負訊號傳送的時間完全一致，使平衡傳輸的共模排拆功能徹底發揮，如此一來使正負噪訊抵銷的效果可以達到最佳狀態。這是 Siltech 首創的一項全新技術從未有人做過。為了讓 Master Crown 平衡訊號線更能適應不同音響系統，線身上有一個屏蔽切換開關，讓使用者可以依照系統狀況選擇平衡接地還是浮地，如果器材都是真平衡，建議選擇平衡接地，若非真平衡，則切換至浮接地試試。同樣重要的是插頭，訊號的終端傳輸發生在插頭上。這就是為什麼所有插頭的接觸針棒均採用 S10+ 單結晶結銀導體，透過特殊的 PVD 製程鍍金，以進一步加強音質。 RCA 插頭上的鎖緊機制已改進，藉此避免渦流風險。

對於 Master Crown 喇叭線，低損耗和低失真是其性能之關鍵，並且線材需要配合良好的器材，透過優化所有參數，確信我們的線材可以在任何音響設備組合上都能發出令人難以置信的聲音。

通過添加MFD（磁場失真）和CSD（電流屏蔽失真）消除技術，Siltech 的新一代Master Crown 創造出令人難以置信的強大聲音，聲音具有極豐富的信息、準確度，最重要的是流暢的動態，即時吸人注目。它可以處理 10kW 的功率，但更重要的是，它還可以讓您聽到 8 飛瓦（0.000000000000008 瓦）的聲音。 這種令人振奮的極緻範圍，使每個微細的聲音細節（或更好；飛細節）都能被聽到，使你的聲音超逼真，並在任何情況下增加一層精細的細節和真實性。

Master Crown 喇叭線採用6 股特粗 S10+ 單結晶純銀導體線芯，完美對稱 Hexagon 六角形排列結構。由於訊號傳輸的終端極為重要，Master Crown 喇叭線上的 S10+ 單結晶純銀叉頭，直接採用 PVD 鍍金技術，可增加音場的深度和聲音質感。

Master Crown電源線對重播音樂具有意想不到的巨大聽覺效果。漏磁會導致特定頻率範圍內失真，從而引發與音樂無關的小失真，也會影響附近所有連接的音響設備和其它（主要是訊號線）線材。此外，這些失真的電流會導致許多電源線飽和，從而在這些峰值電流下產生可聽得見的音染。即使是小型音響設備也可能有 1 安培的重複峰值電流，同時僅從交流電中消耗 10 瓦的能量。在電源線的開發過程中，我們的研究小組使用 COMSOL Multiphysics 等先進軟體和世界上最先進的測量設備來盡可能減少峰值電流產生畸變的影響，其結果使電源擁有極高水平的完整性和令人驚嘆的主觀和客觀表現。

電源線的特殊接地消除了發燒友通常為改善聲音而解除接地的需要。 Siltech 的新型 18 股導體的配置由 S10+ 單結晶銀線和 G9 銀金合金線組成，可極大減少訊號損失和失真，並消除外部幹擾。消除刺耳聲、完全沒有誘發失真以及其後的低頻穩定性，最大電源完整性和極真實音樂還原能力，創造了一種極為真實的現場感。

奇妙的音樂性
在高端音響中，最靈敏、最重要的測量工具就是人耳，才是真正展現 Master Crown 性能和規模之美的因素。沒有其它線材能夠像 Master Crown 一樣準確測量，也沒有其它聽起來如此具有音樂吸引力和真實感。 Master Crown 系列超越了傳統的線材設計，提供無與倫比的聲音清晰度、音場深度和音樂準確性。 從獨奏鋼琴的精緻複雜性直至交響樂團雷鳴般的逐漸高潮，這些線材為每個音符、每個和弦和每個音樂時刻注入了生命。

Date: 2024-11-12

The Octave Audio V 70 is a Class A push-pull pentode integrated amplifier capable of outputing a specified 50 Watts of power into 4 Ohms.

If you read my review of the lovely Octave V 16 Single Ended Integrated/Headphone Amplifier, you know a bit about Octave’s history and how the company’s roots go back to 1968 when Karl Heinz Hofmann founded the transformer winding factory Hofmann in Karlsbad, Germany. His son, Andreas Hofmann took over the Hofmann company from his father in 2000, gave it its new name—OCTAVE Audio—and a focus on the tube-based electronics he’d been designing and building since the 1970s. History is something to respect, imo.

The Octave Audio V 70 Class A Integrated Amplifier incorporates the company’s Dynamic Bias Control and I’ll let them do the talking:

Dynamic Bias Control means that Andreas Hofmann has found ways to dynamically shift the limited dynamic range, and thus the limited power of the Class A concept, according to the requirements. The development of the dynamic operating point setting enabled a self-regulating Class A amplifier with approximately twice the output power of 50 W RMS with up to 70 W (with Super Black Box) peak power.

This technology combines the tonal purity of Class A with the dynamics and performance of push-pull A / B technology.

The modern concept of a Class-A push-pull amplifier in a pentode circuit makes it possible to guarantee the Class-A virtues over the entire frequency response up to maximum modulation. The enormous power, with up to 70 watts peak power, is significantly above the performance level of conventional Class A amplifiers and is more than sufficient for most speakers.

It just so happens I also have Octave’s Super Black Box in for review, so we’ll see what kind of more, beyond power, that brings to the table.

The V 70 comes with a total of 5 line level inputs (3x RCA, 1x XLR, 1x Front Channel/HT Bypass), a Tape In and Pre Out. A MC or MM Phono module are optional. There’s also a single set of speaker binding posts, a Black Box Connector for adding one of Octave external power supplies, a 3-position Ecomode toggle switch (“Ecomode serves to reduce heat and unnecessary power consumption when the unit is switched on but not in use”), and an IEC inlet. I’ll let Octave explain the reason for the Power Selector High/Low switch:

Power High and Low, so that the device can be optimally adapted to different power tubes. Due to the high power in Class A operation, a KT 120 or KT 150 tube must be used for Power High. Less powerful KT88 or 6550 types should be operated at Power Low. Around 15 W Class A and 25 W music power are still available.

The V 70 also ships with a quad of Tung Sol KT120s but you can also use 6550s, KT90s, KT100s, KT120s, and KT150s in their stead. The preamp stage employs a single 12AX7/ECC83 and a pair of 12AT7/ECC81s. The front panel’s two dials dial in input selection (left) which also has a stop for checking the auto-bias of the output tubes while the other dial is for volume control. In between sits a display that shows the selected input, Bias status when in Bias mode, and amp status (Power, Soft Start, Protection, Front Channel).

There’s an included chunk of aluminum remote with but two buttons—good and better. The amp and remote’s matte aluminum finish is a favorite of mine for two reasons—I like the way it captures light and you can touch either without leaving finger smudges. To my mind it makes perfect sense to finish something that’s going to be touched with a touch-proof finish.

Specifications
Output Power: High: 2 x 50 W / 4 ohms; Low: 2 x 25 W / 4 ohms
Frequency response: 20 Hz – 70 kHz @ 50 W – 1 / – 3 dB
Total Harmonic Distortion: 0.1% at 10 W / 4 ohms
Signal-to-noise ratio: – 100 dB / 50 W unrated
Options: Phono MC or MM
Design: Silver or Black
Tube Configuration: 4 x KT 88-S4A-Carbon, optional 4 x KT 120 TS
Inputs : 5 x line level RCA (one is a bypass input and one is a phono input with the phono option) / 1 x XLR
Outputs: 1 x pre-out regulated / 1 x record output RCA / 1 x loudspeaker output
Dimensions: 451 x 150 x 415 mm (W x H x D)
Weight: 22.1 kg