Audio Research PH5  Review

by James Leahy

 

 

 

Introduction

The Audio Research PH5 is the direct replacement to the PH3 and PH3SE and at a lower price than the PH3SE with far greater performance! Does life get any better with a deal like this... The PH5 uses four 6922 vacuum tubes in it's output stage. The newly improved RIAA circuits Audio Research says are taken from the old vaunted Reference Phono unit.

Maybe the biggest change to the PH5 is the new remote control being issued as standard and one is now able to switch cartridge loading 'on the fly' from 47K, 1000, 500, 200, or 100 ohms all from the comfort of one's listening chair. We are getting spoiled here but it is fun never the less. Other functions available via the remote controller or from front panel actuation are, Power On/Off, Mute and Mono.

 

The back panel is a simple yet functional affair with a pair of SE input and outputs plus the obligatory earth point. Front handles are an optional extra on the PH5 and in my book a must have for all true collectors or fussy Audio Research owners. It just completes the look of the unit and brings it into line with the rest of the Audio Research range.

The total gain for the PH5 is factory set to 57.5dB which as Audio Research claim is more than sufficient for even low output MC cartridges. I can attest to this claim personally as I am running an Ortofon Jubilee with output of only 0.340mV. While this is not the lowest output MC cartridge on the market there is still plenty of gain left on my LS26 pre-amplifier when in use.

To understand why a good phono stage is so important for those that do not know or have not already experienced the benefits please read this, 'What's The Most Neglected Component in a Phono System?'

 

 

 

 

 

 

 

 

                                                               Sonic Evaluations

Without any further delay let us see what makes the new PH5 tick and how it compares in a typical Audio Research system. I first allowed my usual 60 minutes of warm-up time before making any serious evaluations and to let the valve circuits stabilize after reaching full operating temperature. Connected firstly to the Audio Research LS26 and VT200 Mk.I the PH5 was something of a landmark in the development of phono stages at a reasonable price as I heard Mick & Keith of the 'Rolling Stones' serve it up on 'Let it Bleed' (Decca, 1969). My reference analogue rig being the slick Rega P7 loaded with Ortofon's finest, being the famous MC Jubilee cartridge which can be very unforgiving of weak phono pre-amplifiers.

 

I am pleased to report that the PH5 handled this ominous task with great ease and then some! The great dynamics that were produced by the PH5 even when mated to a low output cartridge were staggering to all that have heard this combination. Do not underestimate the value of an excellent phono pre-amplifier on your system's analogue performance. Only a fool would discount the real world sonic benefits without first auditioning one against what they are currently using if it was an integrated unit, as the differences are that vast. When the very small details are lost here at the first point of amplification they can NEVER be recovered later in your system.

There is no MM or MC switch on the unit as Audio Research explained to me the circuit was designed to accept even the lowest output MC cartridge on the market and at the same time has been tested with the highest output MM cartridges without producing any measurable distortion. This is an engineering feat of no small note within itself folks. The PH5 is not inherently over warm or bloated nor is it overly detailed. I would describe the soundstage as extremely wide. Spanning in all cases the entire width of my listening room and having a tremendously low noise floor. This was one of the most critical areas of concern for me and I am sure many others that are running low output MC cartridges. Typically if the Phono Stage is not up to presenting a well balanced presentation throughout the full scope of it's dynamic range the mid to high frequency bands can be overly pronounced and shrill at higher volumes.

The image is precision and vocals are liquidly smooth with a touch of warmth, classic Audio Research all over again. The midrange was well controlled and harmonically well developed yet the treble was sufficiently fast and detailed to prevent sonic boredom. There was no hint of grain or grunge/harshness to be heard. However I will say this about what it is to be paired with. The pre-amplifier choice with this unit is critical for the best performance. I tested this unit with a solid state Threshold FET9 pre-amplifier and the magic that surrounded my listening chair was instantly squashed if not somewhat muted and veiled.

The authority exhibited by the PH5 was nothing short of miraculous with the LS26. Regular readers of my reviews will know that I like to feel my music as much as hear it and the combined experience that the PH5 offers will sway even the most ardent critic. Ok, so the PH5 sounds good but just how good compared to something else. I decided to do a head to head with the Audio Research SP15 and the results were interesting to say the least. In short, the PH5 smoked the SP15 when run through one of it's own line level input's and when connected up to the LS26 the soundstage went to a whole other higher level again. The SP15's line stage kept the authenticity of the PH5's character and tonal accuracy and glorious midrange intact without loosing anything when used in this fashion. The PH5 pulled out whole sections of music that were previously buried within the complex musical passages never to see the light of day until the PH5 appeared and showed up the tiniest sonic cues. It was as if the PH5 was playing a different album that was a half speed studio master recording or the like such was the difference in presentation between the two. In other words if you have a decent line level pre-amplifier ideally from Audio Research themselves this phono stage would match perfectly.

 

 

 

Associated review Equipment

  • Amplifiers:          Audio Research VT200 Mk.I

  • Line stage:         Audio Research LS26

  • Speakers:           ScanSpeak & Vifa Custom

  • Cables:              Neotech

  • Cartridge:           Ortofon MC Jubilee

  • Turntable:          Rega P7

  • Subwoofer:         Velodyne HGS-15