Graham Slee has just released a new flagship phono stage (we’ve been using their Elevator EXP MC Step-up Amplifier and Reflex XM phono stage to excellent effect for some time). Called the Accession, it’s a moving magnet sensitivity device with a new take on equalisation and many useful features for the serious vinyl enthusiast.

Equalisation

Firstly it doesn’t do RIAA equalisation like any other phono stage – it does it quite differently. It recognises that magnetic cartridges have what’s called a constant velocity output. In other words their output isn’t flat like most people think – it rises at 6db per octave – and so the cartridge plays its own frequency response as well as playing the record’s frequency response.accession-black-front

The Accession does the RIAA EQ by first equalising the cartridge, then equalising the record, which makes sense seeing these two things came about at different times. Part of the EQ is being caused at the very moment the record is in play (by the cartridge). The other part of the EQ happened at the cutting lathe (many years before??).

Over 99% of phono stages work by equalising the combination of both curves as if the record was recorded with that. No matter how it’s achieved it leads to some interaction of filter slopes requiring “empirical tuning”. With the Accession there is no interaction – calculated values result in the correct response.

It also means that the records own EQ can be switched off using its “Flat/CA” switch to give a constant amplitude response, and so the user can use software EQ reconstruction when digitising via a digital to analogue converter. It also means that acoustic records will be reproduced as flat as they were cut.

Not only that, but as well as having RIAA record equalisation, it also has two other EQ settings: “British” for FFRR LPs and EPs; and “American” for NAB equalised records – great for older mono vinyls. Two front panel switches provide these functions and a third front panel switch selects stereo or mono (left-right sum).

Volume Control & Two Outputs

There are two outputs, one which is fixed level and the other which is via the Accession’s volume (or level) control.

This gives the user the ability to record or digitise (via an ADC) from one output whilst listening on the other. The volume control can be used to set just the right level for an ADC to prevent clipping, or to adjust the signal on quiet records.accession-black-rear

But its other use could be for a frugal vinyl only system where the Accession will oblige by driving a power amp straight from its volume controlled output. The fixed level output can be used to supply a headphone amplifier. Graham Slee HiFi System Components can also supply suitable power amps: the Proprius monoblocks; and has a choice of headphone amplifiers.

But this isn’t all. Four capacitive load settings allow for fine tuning so you can extract the best quality sound from your cartridge.

Combine the Accession with Graham Slee’s Elevator EXP step up amplifier and all of its features are available to moving coil cartridges. The Accession is only supplied with Graham Slee’s best power supply, the PSU1, so it automatically performs to the maximum.

The Accession costs £800 and is available with either black or silver casing from Graham Slee whose ads you will find on this site.

Secifications

Item Measurement
Input and output connectors 360° shielded RCA/phono sockets, hard gold plated
Input sensitivity range 1.6mV to 7.2mV (recommended)
Output range (for above inputs) 190mV to 857mV
Maximum input 35mV rms
Maximum output 5.2V rms
Gain 41.5dB (119) at 1kHz
Input impedance 47k Ohms plus: 100pF / 220pf / 320pf / out
Output impedance (driving impedance) 750 Ohm fixed / 470 Ohm variable (will drive 10k Ohms and above)
Noise at output -66dB Quasi-peak 20Hz to 20kHz
Distortion typically 0.01% 20Hz to 20kHz
RIAA accuracy ± 0.3dB
Frequency response <20Hz – 45kHz (-3dB corrected to RIAA)
Channel balance 0.2dB
Channel separation 60dB
Power supply remotely powered using PSU1 linear power supply
Size (approx.) W: 107 x H: 50 x D: 195 (mm) inc. jacks

 

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