I’ll be honest, here. The conrad-johnson ET3 preamplifier is a remarkable preamp, but I had trepidation about the way it’s being promoted. It’s down to the ‘baby GAT’ thing – the ET3 is being touted as an affordable version of the company’s GAT flagship pre. That, I feared, is setting the ET3 up for a fall; the GAT is so damn good, it’s like calling someone the ‘mini Mozart’. Trouble is, the ET3 is a baby GAT.
The ET3 uses a single Russian-made Electro Harmonix 6922 double triode voltage gain with MOSFET follower circuit acting as a buffer – designed to give the preamp a strikingly low output impedance – and a similar solid-state DC voltage regulator. This is very much in line with the GAT’s circuit. Once again like the GAT, the low impedance means you can use the preamp with long cables between it and the power amplifier.
Functionally, the two are similar. There are six line inputs, a tape and a home cinema loop – all single-ended – all of which are selected through relay switching. The relays are all placed on a stand-alone board to limit their switching clicks from reaching the tubes. The volume control is a discrete, relay-driven design once again similar to the GAT, although lacking balance adjustment (even though the LED read-out has separate left/right levels). This can’t be altered even on the remote handset, even though there are buttons marked out for the task. The remote this time is a slim black plastic unit instead of the thick metal one supplied with the GAT.
Like the GAT, it’s a physically big preamp, right up to the 19” rack limits. The standard, gold front with black crackle cover has been unchanged for decades and the big central display/IR receiver has become a standard feature for some time. The overall fit and finish is very good, and the whole device sits on four thick hard-rubber feet. While not the cutting edge of footer technology, this more than suffices.
The GAT and ET3 preamps do differ – given one costs more than eight times the other, so they should – they share more than you might expect. Things like the separate power supply for the filaments of the valve, a microphony-reducing suspension system and a parts list that reads like a Who’s Who of the best in audio components are all missing from the ET3. That being said, the audio-chain caps are all polypropylene and all the resistors are high-quality metal-film types, but the special Teflon by-pass caps and the field full of Vishay resistors seen in the GAT are what help keep the ET3 price in check. Like all c-j preamps, you need to phase invert the signal at the speaker terminals if you want to keep the sound in absolute phase.
The review sample came fully loaded. Along with the IR remote handset, it also included the built-in and retrofittable high gain phono stage, based on the reference TEA-1, which is has enough gain and low enough noise to be good for moving coil cartridges of 1mV and below. The resistance loading of the phono module is adjustable thanks to two small covered DIP switch arrays. Factory set of 47kOhms, the ET3 board can cope with 9.6kOhm, 1.9kOhm, 200 and 500 ohm loads. The addition of this section adds to the component count on the circuit board, and adds three more tubes – Mullard 12AX7’s – to the roll call. It’s worth pointing out that modern Mullard is also made in Russia, but – like the 6922EH – tube rolling isn’t mandatory, because these standard tubes are pretty damn good in their own rights.
My initial dread about the ET3 was entirely unfounded. I did receive a sample with more than 50 hours on the clock, so I have to take the early break-in sound as hearsay, but that hearsay suggests there’s a magic point at around the 40 hour mark when the ET3 goes from lightweight to wonder-pre. I just got the wonder-pre point.
There are two schools of thought in good preamp design. Both follow the path of ‘first, do no harm’, like some electronic version of the Hippocratic Oath. Where they differ is whether they strive to do no harm to the recording, or the music. The two should be alike, but there seems to be a difference. The ET3, like the GAT before it, manages to make the music come to life whatever the recording. Others are faithful to the recording but the entertainment suffers in the process. This is the big bonus of the GAT, of course, in that it manages to make everything sound right without being sweet, where the ET3 makes everything sound right without being too sweet.
Where the ET3 scores highly is its soundstaging. The preamp – like the GAT before it – presents the listener with an enveloping sense of dimensionality that draws you deeper into the music. This will invariably bring up that great “yes, but is it accurate?” canard from those who will never hear or want to hear the ET3. Those who have and do just don’t care… they love the sound of the preamp, and would do so regardless.