Primare SP31.7 AV Preamp Reviewed

Published On: January 4, 2003
Last Updated on: October 31, 2020
We May Earn From Purchases Via Links

Primare SP31.7 AV Preamp Reviewed

This unit has been replaced by the SP32 which allows LPCM input for the uncompressed codecs of Blu-ray. Audiophiles love the UK flavor of brands like Primare. For a full review of this surround sound processor and or a place for home theater enthusiast to read more...

Primare SP31.7 AV Preamp Reviewed

By Author: Home Theater Review
The staff at is comprised of experts who are dedicated to helping you make better informed buying decisions.

Primare-SP31.7-preamp-reviewed.gifSaying good-bye to something many regard as the finest of its type is painful. No, not the Aston-Martin Vanquish, though that did render me lachrymose. I mean the Lexicon MC-12, as fine an A/V processor as I've ever had the pleasure to experience. Importer CSE, though, is not cruel, so another processor was left in its place the same day they collected the MC-12, and it was as far removed from the Lexicon as one could get.

Nothing was more telling of the change than the Primare SP31.7's front panel: only two rotary controls, four buttons and a display. Oh, and it's roughly half the height of the Lexicon, again suggesting 'stereo pre-amp' rather than 'all-singing, all-dancing digital brothel'.

Additional Resources
Read audiophile grade AV preamp reviews from the likes of Lexicon, Meridian, Krell, Classé, Mark Levinson, Anthem, Sunfire and many others by clicking here.
• Read an Arcam FMJ AV888 AV processor review from Dr. Ken Taraszka.

This sort of minimalism isn't the norm for home cinema processors capable of 192 kHz/24 bit processing for the various shades of Dolby (ProLogic, ProLogic II, Digital 5.1, Digital Surround EX 6.1, Digital Matrix 6.1) and the assorted DTS variants (Neo:6, 5.1, ES 6.1, ES 6.1 Discrete). Little on show, perhaps, but the unit also offers expansion potential for future upgrades, can handle seven channels, and incorporates a 5.1 channel analogue input for DVD-A and SACD. Because of the dearth of buttons, you could easily mistake this for a standard, two-channel analogue pre-amp, not something you can say of the breed of high-end A/V processors (or receivers) that seems conceived to instil techno-fear through the presence of too many controls. And yet at no time could I turn up anything Primare had left out....

The SP31.7 uses Primare's own proprietary DSP, developed by designer Mike Bladeleus and the Primare team, a chip 'which combines with superior analogue circuitry to deliver a class-leading range of processing options, including a 7.1 channel mode, and an elevated standard of multi-channel audio and video reproduction.' Designed to complement Primare's CD/DVD players, it was conceived from the outset to ensure that the two-channel brigade had nothing to moan about, and that bare front panel is the key.

If you think back to the earliest top-loading CD players, was is not merely sleight-of-hand to remind analoguistas of their beloved turntables with top-opening dustcovers? If this sounds like psychological trickery far too subtle for the audio industry, then you're probably right - hi-fi prefers to use a tactical nuke to kill a fly - but that's the take I get from it, and the Primare didn't disappoint. It just may be the easiest-on-the-ears separate A/V processor around. But if you can kid yourself, too, that it's a stereo pre-amp, so much the better if you're the sort who has 'issues' with multi-channel. In which case, why have you read this far?

But the Swedes are thinking of people just like you. Primare's stated dictum is that '...the SP31.7 disproves the idea that exceptional stereo performance from analogue sources must be compromised by the inclusion of digital processing and video circuitry. The SP31.7 is designed as two totally separate units mounted in one case: a fully-balanced pure analogue stereo preamplifier, and, via independent power supplies, a high quality 7.1 channel Dolby Digital & DTS processor with full video switching.'

To reach a goal of ensuring that analogue stereo can live side-by-side with home theatre - achieved by many others, but still with huge, cluttered boxes - Bladeleus included details such as balanced output for the stereo channels, a proper bypass mode to avoid the processing and independently adjustable crossover points and output levels for every speaker in every surround format. Thus, each mode can be optimised, say, to allow the user to operate the front channels in absolutely full-range fashion when listening to pure music, and then switch the same primary channels to a 60Hz crossover point for Dolby Digital and an 80Hz crossover for DTS.

And be not deceived by dimensions of a mere 430x385x100mm (WDH). The Primare will still handle more components than even the saddest of videophiles can imagine; thoughtfully, you can configure the rotary so it only scrolls through those that are in use. In my case, I had it set up for satellite/TV (Sky), analogue VCR (Sony), DVD player (Rotel RDV-1080), direct CD (from the Rotel, and the Sony '333 SACD player) and LaserDisc (Pioneer DV919L). Thus, I was unaware during day-to-day use that the Primare accommodates a mighty digital inputs and video inputs.

Although the front only shows you control of source select and volume via rotaries, and buttons to choose menu, select, level and standby, the back is filled to the edges with the following audio inputs: an XLR AES/EBU digital, five coaxial digital, two TOSlink digital optical, a pair of XLR balanced analogue, seven pairs of coaxial RCA analogue. Outputs? How about: one coaxial and one TOSlink digital output, a pair of XLR balanced analogue outputs for the main left and right stereo channels, and RCAs for all channels including a brace of subwoofers, and a pair for analogue record out.

Then there's the video: two for full component video, plus one for component output, three s-video in and two s-video out, four composite video in (via RCA) and one for main out and one for record. And, to ensure full compatibility with custom installations and multi-room, there are four programmable 12 volt triggers through optional interface), full RS232 and discrete IR control, a microphone input and remote output. The support for custom installation allows the processor to be controlled via a wide range of home automation touch screen controllers, e.g. Crestron, while the onboard triggers can allow control over partnering components or such video necessities as screens and blinds. (The unit comes with two remotes of differing complexity, Oh, I almost forgot: there's also an IEC input for the, er, mains.

Confession time: although I watched him do it, CSE's Adrian Blundell set up the Primare. Although not as daunting as the Lexicon, which comes with its own take on , the Primare's 28-page manual looks like something you'd get with your copy of Adobe Photoshop. And I didn't feel too guilty because CSE confirmed that they expect a dealer to set this up in the customer's home, not let the poor bastard suffer a two-day learning curve before he can watch a movie. If that sounds like a cop-out, so be it; just note that it's the norm because a multi-channel system is blindingly more complex than a CD-player-amp speakers rig.

Here's but a part of the litany of set-up parameters: assigning components to inputs, setting the displays, setting delays via speaker distance, setting speaker levels, adjusting bass management through speaker crossover settings from 30Hz-150Hz in 10Hz steps, assigning parameters to different sources, blanking off unused inputs, assigning default surround modes (e.g. you don't need DTS for TV playback), ad infinitum. Let's look at it another way. Adrian turned up and simply substituted the Primare for the Lexicon in an existing set-up, . Still, he was there for the better part of five hours. It would have taken me two days, minimum.

As for the rest of the system, the Primare controlled the above-listed sources, a Theta Intrepid amplifier, two Martin Logan Ascents, Cinema centre channel, Descent subwoofer and Scenarios at the back. The screen was a Marantz FL4200 plasma, and the majority of the wiring came from Chord. So, I was auditioning the Primare and nothing else, in a system that had been unchanged for some months. The transformation was NOT subtle.

What quickly transpired was a familiar audio phenomenon: the Lexicon and the Primare are so different that it made it more difficult rather than easier to assess the changes. Yes, I know that the Lexicon isn't to everyone's tastes; a colleagues whom I respect without reservation simply cannot get on with it, finding it sterile and hearing the sound sliced-up into five channels. He uses dynamic speakers, I use dipole ESLs, so we agree to disagree, relative to our own system conditions. Conversely, the MC-12 gave me a delicious 360 degree surround, but will admit to a hint of uber-clarity that some may find the be the very element that makes multi-channel a no-no. We are not talking 300Bs and vinyl here.

But the Primare? It's soft and sweet and lush, all-enveloping with the efficacy of the Lexicon, but with far less concern for minuscule detail than it is for overall consistency and 'musicality'. I seem to recall years ago defending my love for valves by saying that I preferred a glorious lie to distasteful truth - my way of saying that sonic accuracy isn't the be-all, end-all - and the Primare errs on the side of music. Call it 'sonic air-brushing', the reason why the latest 16-year-old starlet is zit-free on the cover of a colour supplement. I can live with it.

Let's deal with the video switching first. Perhaps a 42in plasma isn't enough to make this revelation worrisome, but there was a barely perceptible drop in absolute visual clarity. To detect this, you needed shots like close-ups of actors' chins, if counting stubble is your arbiter. It was enough, though, to minimise some of the benefit of SuperBit discs. Would it be exacerbated by a full-blown projector and a 15ft screen? Probably. But I was at no time concerned with the change. I'd seen far greater variance between DVD players, e.g. the Rotel vs the Pioneer. Suffice it to say, videophiles will not be dissatisfied with the switching. Then again, the most sophisticated systems would not channel the video signals through the processor anyway, but rely instead on the installer to feed the video directly to the projector or screen, with the switching accomplished by the remote control.

So back to the sound.

Like many videophiles, I now have - after five years - a fairly healthy library from which to choose. And certain 'winners' have emerged in the sound stakes. Eric Clapton's , ELO's and the Band's (oh, and the inevitable Eagles...) are fine tests of the music capabilities in surround mode. For pure music, I played Eric Bibb's , the stereo SACD of the Kinks' , and a pirate CD of Mickey Katz's Capitol recordings.

, and are among the favourites I viewed and auditioned for movie soundtrack retrieval. Additionally, the following films were viewed during the loan period: ( recommended!), , the revised , , the new edition of , , and the recently-released Jack Ryan box set, sticking with DTS over Dolby where applicable.,>

Inject dose of schizophrenia here: the Primare is so, so , so easy-on-the-ear that I had a slight contretemps with a colleague who wanted to defend the Lexicon. And, hey, I'm not going to deny that I'd take the Lexicon over the Primare hands-down. But it wouldn't be snap a decision, because the Primare does things that will soften the heart of the most bigoted of analoguistas. It demonstrates a warmth that is missing from nearly every A/V processor I've heard bar the balanced-mode, seriously expensive Theta Casablanca. It exploits Martin Logan's 'spread' with the most all-enveloping blanket of sound you could want, while reinforcing the rear effects channels, despite their sound pressure levels having been set to the decibel. It matched the truly discrete, directionality of the Lexicon, without the merest whiff of disembodiment my colleague attributes to Lexicons.

Put it another way: I was able to watch three episodes in a row of (one of my secret, dark, nay perverse pleasures...) without any listener fatigue, and that's just plain vanilla Dolby Surround quality. Old mono films with suspect soundtracks? No problem: I even watched a genuinely shitty transfer of an obscure 1930s Bogart film, devoid of the benefits of major label remastering, and worried not about the utter loss of dynamic contrasts.

Read more on page 2


Even viewing of programs via Sky was a delight, especially the way the Primare prevented audience applause from sounding like Rice Crispies, and laughter from decaying to a dull roar. This preamp processor, purely and simply, handles sound with the respect and finesse that you lot seem prepared only to attribute to purist audio components. This could be the product that makes the scales fall from your ears.

As for a lone complaint? So spoiled am I by the comprehensive nature of the Rotel DVD-Audio and Sony SACD players' displays that I was left wanting by the minimalism of the Primare's info panel. Silly, I know, but I love the reassurance of a display that tells you what speakers are in operation, sampling rates, what flavour or Dolby or DTS you're using and other non-essential but comforting data. And the on-screen display? OK, but graphically nothing to worry Spielberg.

Normally, you don't expect this level of utter competence from a small specialist. It's been the Achilles' heel of so many of the purist makes that I'm no longer surprised when a much revered analogue/stereo brand fails miserably with its bid for a slice of the multi-channel pie. Sorry, but video and multi-channel ain't as simple as two-channel analogue, as many are finding out the hard way. For the most part, they're merely re-boxing someone else's technology. Primare is one of very few specialists to manage the seemingly-impossible: creating an A/V processor with the usefulness and competence of a Japanese A/V receiver, yet - miracle of miracles - at a price that's not in keeping with Theta, Mark Levinson, Krell or, yes, Lexicon. The Primare SP31.7, you see, costs only 2500.

'Only'? Yes: 'only', because you would eagerly pay that price for a conventional, two-channel, analogue pre-amp with this sound quality. It is a marvellous product, and must be commended for doing more bridge-building between the pro- and anti-multi-channel types than any I can name below, say, 4000. You get superb two-channel performance (with the proviso that we're talking about CD rather than vinyl) and utterly delicious surround sound performance, in a package that won't unhinge those with buttonophobia.

And now the Primare has gone back to CSE. Guess what? I miss it nearly as much as the Lexicon MC-12. At three times the price....

The Matching Amps
Thanks to a savage shipper, this review turned from a study of the SP31.7 and one of its matching power amps in the 30 Series to the solo review you're holding. Better for me, I thought, as it allowed me to concentrate on the processor through the familiar Theta Intrepid. But, out of duty, I thought you should know (especially if you're the sort who - wisely - likes same-brand pre/power pairings) what the natural mates are for the Primare. The matching amps, designed to address include:

A30.5: 140W/ch, five channels, price 1700 
A30.3: 140W/ch, three channels, price 1300
A30.2: 140W/ch, two channels, price 1200

All feature fully independent power supplies and one massively specified transformer per channel, plus 12V triggers. Alas, all I can tell you is that the amplifier they brought along looked great. Too bad about the rattling noises when it was shaken. KK

Subscribe To Home Theater Review

Get the latest weekly home theater news, sweepstakes and special offers delivered right to your inbox
Email Subscribe
HomeTheaterReview Rating
Overall Rating: 
© JRW Publishing Company, 2023
As an Amazon Associate we may earn from qualifying purchases.

linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram
Share to...