Vincent Audio SV-737 Integrated Amplifier

What do we have here? A compact, modestly powered, polite, integrated Euro-amp? Not quite. The $3499 Vincent SV-737 is a big, heavy, beefy, bratwurst-mit-sauerkraut-eating German power amp that just happens to have a fine onboard tube preamp section and onboard DAC and Wi-Fi, too. True, its integrated nature will save space to make it more attractive to apartment dwellers, giving it a higher value in terms of price/features and price/performance. However, its size and looks suggest that it can pump some serious current into your speakers, and, indeed, it is rated at 180Wpc into 8 ohms and 300Wpc into 4 ohms.

Hybrid in more ways than one, the SV-737 features a tube preamp section with a proudly displayed 85A2 (German-made NOS) tube upfront as a voltage regulator. Two 6N1P and two 6N2P tubes do the work behind the scenes in the preamp stage. In some ways, having tubes in the low-level signal sections of a component is optimal. They make very linear voltage amplifiers, allowing you to design simple circuits with low feedback that sound great, but they don’t have much current gain. Transistors, on the other hand, have a lot of current gain, so they match well with the low impedances of speakers without needing transformers in-between. I have noticed over the years that output transformers in amps can sometimes muffle high-frequency detail. Can this Vincent mix the best of both worlds?

Vincent calls the SV-737 a Class A/AB amp, since it operates in Class A up to 10Wpc (which covers most of the listening I do). That is the way that all Class AB power amps work; they run in Class A up to a particular output power (determined by the amount of bias current) then, above that, operate in Class B. Other amps might not be able to go as far as the Vincent does in Class A, however. (Something between 1–5 watts is more typical, since Class A operation necessitates large, expensive power supplies and heatsinks and large numbers of output transistors.) The Vincent runs pretty warm; you won’t want to place anything on top of it, though seating it on a shelf might work as long as there are at least 3–4 inches of open space above. It’s very attractive with its thick aluminum front panel, large knobs, tube window, and large heat sinks. Judging from the build-quality, there is no mistaking that it’s a high-end unit made to last.

Most of its “Tube Line” (Vincent also offers a more affordable solid-state line) is engineered and designed in Germany, and manufactured in China, as is this model. Like many other recent integrated amps, it includes a DAC and digital inputs. However, Vincent takes this one step further with Bluetooth and Wi-Fi inputs. You can stream directly to it with no other network hardware needed (other than a standard Wi-Fi router), using Vincent apps called “Legacy Player,” “Bobblestone,” or “Medion X” for Android or iOS. (See Vincent’s online owner’s manual for instructions; I couldn’t find the first two available on Android in the USA, so I used Medion X.)

Design Details

Starting up front, there are four classic-looking knobs for volume, input select, and bass and treble. Below the tube window in the middle is the power button, then on the left you have a ¼” headphone jack, an analog/digital button, a tone-control bypass, and input indicator lights. On the bottom right there are more indicators, speaker A/B select, and a WPS button for Wi-Fi connection. The unit comes with a nice remote control, modestly sized and made of metal instead of plastic. 

At the rear are two coaxial SPDIF digital inputs, two TosLink optical, and connectors for the Wi-Fi and included Bluetooth antennae. For analog you have six line inputs on RCA, but no balanced and no phono. There are also pre-out/main-in and record-out outputs, two sets of stereo binding posts for speakers (switchable), a standard IEC connector for the power cord, and two trigger control outputs at 12V.

When you turn it on, the red light on the volume control knob (indicates position) blinks red to let you know that the tubes and the circuits are warming up. The unit does not produce any sound during this period, for about 40 seconds. This automatic warmup helps extend tube life. As with many types of components, however, I found the sound of the Vincent improves after it warms up for quite a few minutes, until it reaches an equilibrium (and the heat sinks are warm). The light comes on briefly showing you volume-knob position when using the remote also, but I wish it would stay on. It is not easy to see from more than 5 feet away when it is not lit up.

Listening Impressions

The first thing I thought when listening after the break-in period (at least 50 hours of medium-volume music) was that this was a very-good-sounding amp, but a little bright. Part of this response was my fault; I had paired it with super-detailed but leaning-to- the-bright-side Shunyata Delta v2 bi-wire speaker cables. Selling for nearly the same price as the Vincent, they may not be representative of what people would use with this amp, but they are in many ways the best-sounding cables I have on hand right now. The Vincent was certainly very lively and detailed, but did it sound tube-like? By definition yes—it uses tubes. However, it does not have all the smooth, forgiving sound of a classic tube power amp, but then again, many recent tube-amp offerings might not sound like that anymore. Personally, I am not a huge fan of very forgiving components anyway; they tend to only sound great if other parts of the system or the recording have too much of an edge or are too bright. The Paradigm Premier 800f speakers I was pairing the amp with most of the time are a touch forgiving in the treble, so it was a good match there. I also tried it with the Paradigm Founder 80fs, which are not as forgiving, but overall helped the Vincent strut its stuff, as well.

As stated earlier, I typically listen at low levels, at or below 10 watts (my reference single-ended amps have no more than 15Wpc). So, for much of my auditioning the Vincent was running in Class A. I did crank up the volume to higher levels—what some listeners might consider typical or party loud—with the “Roll the Bones” CD by Rush from The Studio Albums 1989–2007 (Anthem 8122796508). The amp still sounded very good. Though the character of the sound had not changed drastically, I could tell it was not in Class A anymore. There was a slight “ragged edge,” which manifested itself as grain in the voices of different instruments, as well as less tight and coherent transient attacks. Keep in mind the difference was very small, but those of us who often live on a steady diet of pure Class A may notice the difference. 

Many, I’m sure, would be perfectly happy with the Vincent’s Class B sound at high volumes, particularly due to the prominent presentation of the bass and overt display of detail. Certainly, it was not coming anywhere close to where measurable distortion was high (>1%). It’s nice to know you have plenty of headroom when you feel like pumping it up. This experience reminded me of when I owned a pair of Muse Model 150 monoblock power amps. I modified them slightly with better parts and adjusted the bias current to the output stage. When I turned up the bias a little, the Muses ran warmer and sounded better. They were running higher in Class A, so that most of my listening did not take them into Class B operation. Officially, I must recommend that you do not try to modify your electronics; doing so could void the warranty, or you could break them (not to mention the fact that you could cause them to overheat while idling or shorten their life span). But I’m a modder. I modify audio gear; it’s what I do.

Speaking of modifications, those two little plastic-insulated metal jumpers that connect the pre-out to the main-in jacks? Common things, I have some on my old NAD 3020 integrated from the 70s too (without the plastic). It’s not so much that they are covered in a plastic, which is not PTFE or some other good dielectric (none of which are as good as air, anyway), but that they are made from nickel-coated steel. Through listening comparisons with similar nickel or gold-plated steel jumpers that are provided for bi-wire speaker binding posts (when using single-wire cables), I have found that these are fiendish, horrible things that you do not want in the signal path anywhere. They can really ruin the sound; I’m not kidding. So, I swapped in some solid-copper jumpers made from 10-gauge Romex with the insulation removed. Easy to make and inexpensive, these improved the sound. Timbres were more liquid; vocals and instruments with a lot of treble sounded smoother and more realistic.

Next, I wanted to do some listening comparisons, starting with streaming vs. streaming with the Bluesound Powernode 2i ($949). It’s easier to tell exactly what you have when you make close-in-time comparisons with competitive products. On Icehouse’s White Heat, a compilation of biggest hits remastered with really exciting sonic qualities (Tidal 16/44), things sounded very well balanced with the Powernode. But when I switched to the SV-737, instruments had better separation, and small details stood out of the mix better. Timbres were smoother and had more noticeable reverb. The bass was more solid and meaty, serving the rhythm section well. The Powernode, on the other hand, had a touch more dynamics and a more balanced lower treble. Other than that, the Vincent amp was preferable, proving why it is more than three times the price of the Bluesound. The Powernode made a good showing, coming closer than one might expect in sonics considering its affordable price, but for those wanting that extra measure of realism and excitement, the SV-737 was a real upgrade.

Not being able to leave well enough alone, I wanted more of a slice of the magnificence and refinement coming out of my reference system daily. Can you use a fiber-optic connection for reducing the jitter of streaming sources when there is no Ethernet input on the streamer/amp? Yes, you can (for as little as $150 in parts; see Stephen Scharf’s feature article in Issue 305), by hooking up the output from a Sonore optical-Module deluxe via Shunyata Delta v2 Ethernet to a Wi-Fi access point, then connecting the Android tablet to that Wi-Fi instead of your main house router. You then log into the Medion X app, and then log into Tidal again. With the optical connection, the Vincent sounded like the best of both worlds; no, make that the best of three worlds: digital streaming, tube, and solid-state! Keep in mind, though, that Tidal is native on Medion X, but it doesn’t offer other full-quality, uncompressed services like Qobuz, Deezer, or Apple. 

On Bad Company’s “Straight Shooter,” timbres were even more liquid and analog-like. Reverb was more noticeable and pleasing, and there was more info about the room the track was recorded in. Images were more solid and convincing. Guitars and voices were starting to fool me into thinking they were live. The sound was so enjoyable that I didn’t want to stop listening. The Wi-Fi nasties had been mostly tamed by my jitter-reduction optical network link. I could hear the better qualities of the built-in DAC now, and it jumped up a notch in my esteem. When I switched to the Powernode again, images had less separation, making it harder to hear each musical line. The upper bass and midrange sounded a little threadbare, missing the meaty rock & roll momentum that the Vincent had. The Powernode had slightly better dynamics, and drums were more noticeable, but other than that the Vincent SV-737 won out in every other category.

I next compared the Vincent to the other overachieving integrated amp I have on hand, the Cambridge CXA-81 ($1299). The Cambridge has no streaming and does not include as serious a DAC as the Vincent and the Bluesound do, so I just listened from CD via the Cambridge CXC transport and Cambridge DacMagic 200m DAC, with an Ultra Jitterbug in-between to remove jitter. On Generations by Journey, the Cambridge really shined, giving the different instruments and voices equal weight, and letting me focus in on whatever part of the music I wanted to, while still allowing me to hear the whole meshing together well, too. Switching to the Vincent, again I noticed the prominent bass (good for rock) and that tube midrange magic, seducing me on male vocals and electric guitar. Some aspects of the sound were better, for sure, but not all. The Cambridge had a more realistic upper treble and top octave, clearer and more communicative in the highest frequencies. And drums and cymbals were a bit more convincing on the CXA81. Overall, this showdown went in favor of the SV-737 again, but not by as wide a margin as it held over the Bluesound Powernode. Here we were comparing less—just the preamp and power amp sections—but the Cambridge CXA81 confirmed what a phenomenal value it is again, at just a little more than one third the price of the Vincent. 

I also did some headphone listening with the affordable Tascam TH-07 over-the-ear monitors. Another publication performed lab measurements on the Vincent SV-737 and remarked that they were not as impressed with the headphone output as they were with the amp. I must disagree, I found the headphone performed excellently. When comparing the Vincent’s headphone-out to that of the Bluesound Powernode on Boston’s self-titled album (Tidal MQA), I came to same conclusions I reached when listening through speakers. The Vincent was superior. And when comparing it to the headphone-output of the DacMagic 200m, I preferred the Vincent, as well. To my surprise, a touch of tube glow was more exciting and more lively sounding than going without a separate preamp. 

So, there you have it; the Vincent SV-737 is a great all-around performer with high power output and refined sound that make it worth the asking price. My listening comparisons confirmed it is a significant step up in sound quality from other good amps in the $900–$1500 range. In some ways it is the best of both worlds, proving the value of a carefully designed hybrid (tube+transistor) approach. The SV-737 is very versatile, as well, with plenty of analog and digital input options and a commensurate-quality onboard DAC. It even accommodates today’s streaming music from phones and tablets, though you will want to have a Tidal HiFi Plus subscription for the highest-resolution tracks.

Specs & Pricing

Type: Stereo integrated amplifier, hybrid with DAC (tube preamp, transistor power amp)
Power output: 180Wpc into 8 ohms, 300Wpc into 4 ohms
Inputs: 6x analog RCA, 2x optical digital, 2x coaxial digital, main amp in
Streaming: Wi-Fi and Bluetooth, proprietary iOS/Android app
Outputs: RCA preamplifier outputs, RCA record outputs, two pair speaker terminals
Input impedance: 47k ohm
Frequency response: 20Hz–20 kHz ±0.3dB; 20Hz–50kHz, ±1dB
Harmonic distortion: <0.02%
Signal-to-noise ratio: >90dB
Dimensions: 6.5″ x 16.9″ x 16.9″
Weight: 46.3 lbs.
Price: $3499 

PANGEA AUDIO DISTRIBUTING (U.S. Distributor)
5500 Executive Parkway SE
Grand Rapids, MI 49512
(616) 885-9818
pangeaaudio.com

Associated Equipment
Sources: Cambridge Audio CXC CD transport with DacMagic 200m DAC, or CXN v2 streamer/DAC, Sonic Frontiers Ultrajitterbug. Streaming from optical ethernet link with generic FMC upstream and Sonore opticalModule Deluxe downstream
Integrated amps: STAMINA single-ended Class-A MOSFET monoblocks, Cambridge Audio CXA81, Bluesound Powernode 2i
Loudspeakers: Paradigm Founder 80f, Paradigm Premier 800f
Digital cables: Shunyata Research Alpha V2 and Delta V2 ethernet, AudioQuest Cinnamon ethernet, Shunyata Delta V2 SPDIF
Analog cables: Shunyata Delta V2 RCA, Kimber Hero, Alpha Core Goertz MicroPurl AG, AudioQuest Mackenzie XLR interconnects; Shunyata Delta V2 and Alpha Core Goertz MI 2T bi-wire speaker
A/C power: AudioQuest NRG-Z3 and NRG-Y3 cables, Shunyata Venom NR-V10 and NR-V12 cables, AudioQuest Niagara 1200 conditioner, Audioprism Power Foundation III, isolation transformers (x4, for network gear)