Graham Slee Elevator EXP MC Step-Up Amplifier

Make Your MM Stereo Phono Amp Do Moving Coil

The Elevator EXP is designed to step-up the tiny moving coil signal to the moving magnet level of a hi-fi phono amp input.

It Also Let's You Adjust To Taste

Whereas some moving coil cartridges will happily give their best with 100 Ω loading, others can be quite particular.

Rather than fiddling around with links or DIP switches, the Elevator EXP gives you all its loading options up front, right there on the front panel - making it easy to get your sound right.

The Differences Between The Elevator EXP And S.U.T.s

Part 1: the hum

For a start, the Elevator EXP doesn't hum. Transformers do. To be correct, the transformer itself doesn't hum, but the magnetic surrounding fields easily get induced into it.

These magnetic fields are predominantly mains-borne. There are a number of hum sources including all your mains powered equipment, surrounding mains powered products, and even the wiring you see, and the house wiring you don't see - all emitting magnetic fields by differing amounts.

The SUT, being a transformer, is influenced by them all. The result is hum. No matter how well shielded its case or how well you carefully position it, in most cases that isn't very successful.

The Elevator EXP is an amplifier - it doesn't contain a transformer so it's harder for hum to be induced into it.

Part 2: weird things to do with the bass

Bass frequencies are the lowest audio frequencies, below which everything becomes DC or direct current. DC doesn't commutate from positive to negative - it doesn't 'cycle' - so it cannot be transformed. Low bass frequencies to a transformer move so slow that they're 'almost DC', As a result transformers distort most of all at low frequencies.

All sorts of tricks and adjustments are employed to reduce this distortion - many include the use of expensive metals and labour intensive winding techniques in a bid to overcome the bass distortion. This is why good S.U.T.s are so expensive.

But the distortion is never really overcome and in the place of detailed bass, all the transformer can really do is 'fudge' the sound. You might have heard people refer to the bass they get as a 'smooth chocolatey sound'? I suppose that's similar to fudge...

The electronics of the Elevator EXP however, don't cause anywhere near such levels of distortion, so all the bass details - the layering and the timbre (the characteristic sound of an instrument or voice) is there to be heard and enjoyed.

Part 3: 'signal theft'

All transformers require excitation current before they will pass any signal. Where do you think the S.U.T. gets its excitation current from?

Has it a power supply? No. So obviously it uses some of the signal as excitation current.

That would be OK but for the fact that magnetic cartridges don't have a linear response - their bass is much weaker than the highs, and so more is 'stolen' from the lows.

That's the reason you'll often see additional components inside a S.U.T.'s casing - these being used to straighten-out the frequency response.

I think you'll agree by now that the Elevator EXP step-up amplifier is the better option.

Suitable Cartridges

Low output moving coil (MC) with output in the region of 0.15 - 0.8 mV (ref 1kHz at 5cm/sec)

The Elevator EXP must always be used between cartridge and a moving magnet sensitivity input. It must never be used 'post EQ' - after the moving magnet phono preamp.

Specifications subject to alteration without notice in keeping with the manufacturers continuous improvement policy.

You can read more about these products at www.hifisystemcomponents.com where you can also subscribe to the excellent forum and discuss all matters relevant to Graham Slee products

Reviews