EAR-Yoshino 834
Hi-Fi World, by Eric Braithwaite








EAR Here

After all these years of elephantine valve designs that take up inordinate space in the living room, there’s a new trend developing. It’s the integrated valve amplifier and Tim de Paravicini’s Esoteric Audio Research company is the latest to combine power and preamp into a single, more domestically friendly package.

Not that the EAR 834 is reduced to the size of the fifties Pye Mozart we look at this month; the numbers refer to the eight EL34s that populate the top of the chassis. (Well, they should, but our sample was supplied with 6L6s.) With that array, you still need a certain amount of square footage. All the same, the 834 doesn't occupy much more space than my Gyrodec. It's also user-friendly. This valve amplifier, according to Tim, doesn't need any complicated fiddling with re-biasing and it has just two controls on the shiny brass faceplate.

A Luscious Feel

As always with EAR products, these controls have a luscious feel. The selector knob for the six inputs clicks smoothly round and the volume knob turns as though it has a traction engine's flywheel behind it. This sort of thing exudes quality and has the customer feeling his money is well-spent on a product of rare quality.

There's always a quirk to Paravicini designs. This time it’s the grilles which cover the bottles. The shape of the black metal grilles which protect the valves, Tim says, is based on the roof of King's Cross station. It's certainly more interesting than the square hampster cage that covers the hotter parts of many valve amps. I'd have gone for the Quai d'Orsay, myself, but at least we’re lucky it wasn’t Richard Rogers' Beaubourg or Lloyds building that caught his eye when he was thinking about valve covers for the 834.

The grilles are normally fixed; a good thing, because while eight valves don't run hot enough for the central heating to be turned off, the 834 isn't exactly a refrigerator. It needs a fair amount of space for convection above and around it. There’s a small degree of hum from the mains transformer, which also makes it advisable for the amplifier to be sited well away from the listening seat.

There’s a recognisable ‘house-style’ to the EAR sound. It’s characterised by a very fine sense of detail. Especially in the mid-range and treble - which is why you’ll find EAR power amplifiers credited in the small print on the back page of a CD insert as being used by producers and engineers for mastering. As an example, on Paul Simon’s Graceland, listen for a triangle very quietly pinging away far back on the right. Bet you didn’t know it was there, with all the backing vocals, guitars and the drumming around it. Hear a guitar chord stop dead with a twang, instead of wobbling indeterminately away into background mush. Listen for a drum firmly and heavily thumped - and then a fraction of a second of dead, deep, almost anechoic silence.

These are some of the trademarks of EAR, along with a forward presentation that has instrumentalists and vocalists stepping out onto the carpet, well in front of the speakers. They make for a sound that is as tight as a guy-rope and as fast as closing a coal-mine

Acoustic instruments fare particularly well. I was listening to Mary Black when I suddenly realised, deep into the performance, that I was hearing a rather better quality of piano than I thought was there. It was broader and fuller - and reached very deep. That wasn’t only in the notes, either, but in terms of physical scale. Where we approach a ‘studio’ presentation again - one I like, but might be too severe for some – is that the 834 focuses as much on a vocalist’s microphone as her physical presence. Hearing a near-disembodied head in front of speakers on some close-miked vocal recordings is disconcerting, but the truthfulness of it can’t be denied.

Not a Comfort Blanket

It’s at this point that a warning note creeps in. If you want a tear-jerking enhanced over-emotional experience in your living room, then this EAR integrated is going to look you in the eye rather coolly and your hanky will stay dry. We’re not in the business here of equating valve sound with a warm comfort blanket. On female vocals like Mary Black’s, there is something of a cut-glass edge at times where other amplifiers of the valve persuasion will soften it with jeweller's rouge.

It was intriguing that friends more used to solid-state revelled in the clarity and the image precision, while others with more experience of valves were somewhat taken aback by it. One of the former - who leaves my listening room at speed at the first sign of distortion – loved it, one of the latter found it too concentrated to live with. Another, used to a gentler top and bottom end, sat back admiring and said the EAR was a valve amplifier for Naim lovers.

In some ways that’s overstating the case, but the EAR 834 is certainly powerful, precise, detailed and vivid. In common with other Paravicini designs, it has a very tight grip on every kind of music and won’t let go. Even down in the bass, it thunders away; the sharpness of definition just a trifle looser than the extremely muscular solid-state variety, but far tighter and tauter than other valve rivals. It’s beautifully made, too, with that thick gleaming fascia exciting unequivocal admiration. There’s only one snag; much as it looks as though it will deal with those nasty panel-speaker loads that dip down to nearly no ohms at all, it’s strictly for 8 ohm impedance loudspeakers.

Several friends put it on their shopping list, so I suspect will many others.






MEASURED PERFORMANCE

Esoteric Audio Research products are designed by someone I regard as the Patron Saint of valve design - Tim de Paravicini. Although - perhaps surprisingly - Tim has no inbuilt prejudice against the transistor and has produced many excellent solid state amps for others (e.g. Musical Fidelity and John Shearne) for himself he designs valve amps - and valve tuners, and valve stereo decoders, and valve microphones and valve cutting amps - and anything else to do with valves. He designed the renowned Lux valve amplifiers, when he worked for the company in Japan.

Like many dedicated engineers with a rare and deep specialist knowledge, Tim designs as much as possible himself. This includes the difficult but crucial output transformers of a valve amplifier, something at which he is an expert. Tim's trannys are special; I measure them and know well that they keep his valve amps a good nose ahead in the field by providing more output at high and low frequencies. Also, most feedback is taken from tappings on the primary winding. This means the load does not affect feedback behaviour, something that makes many valve amps sound awful with electrostatic loudspeakers. The 834 can drive electrostatics, being unaffected by difficult loads.

Which brings us to his new 834 integrated amplifier. The little tranny stacks at the back might suggest all sorts of limitations, like 20 watts output maximum, with plenty of distortion. In fact, the 834 gives an easy 40 watts per channel and 0.02% distortion (innocuous second harmonic), when delivering one watt of output in the mid-band (I kHz). This means it will deliver a dean, distortion free sound at ordinary volumes.

Valve amps do go a bit wonky at extremes of frequency and power output. The 834 is no exception; at l0kHz distortion rose to 0.4%, but mainly second harmonic, but with some higher order components too. Although the distortion is high, the type of distortion produced will not sound especially nasty.

In use valve amps stay clean and sweet sounding if they are not pushed too hard. Their innate smoothness and openness has nothing to do with distortion, as some would suggest. Mid-band overload produces progressively more muddle and confusion, rather than the hard rasping sound of a solid state amp. Treble overload is rarer, due to the energy distribution of music, but when it occurs even valve amps can rasp a little and the treble will get 'dirty' sounding. Transistor amps sound nasty immediately they overload; valve amps will take a lot more stick before they start to sound nasty, appearing to go louder.

So the EAR 834 turns out 40 watts per channel into eight ohms, but less into other impedances, since it caters only for eight ohm loudspeakers (now 4R and 8R) and valve amplifiers have to match their load for best power transfer. Connect up a four ohm loudspeaker and power will drop, unlike a solid state amp where it will rise. This is a property of valve amps in general I should point out, not just the EAR 834.

The output available is enough to make a normal loudspeaker go loud in any room of small-to-average size, but not very loud. The 834 is more powerful than most rivals, which commonly produce 15-30 watts. I find low output valve amps frustrating in that they can sound superb at moderate volume, yet resist being turned up, at least with modern inefficient loudspeakers. The 834 is a little less restricted in this sense, although on a watts/cost basis, no valve amp is a bargain. including this one.

The CD, tuner and tape inputs all run through the selector switch straight to the volume control, as with most modern amplifiers. Frequency response was wide enough to complement CD, reaching right down to 5 Hz. The upper limit was a sensible 35 kHz. With noise down at -92 dB and virtually no hum, the 834 is quiet, but this is to be expected from Tim

Here's a straightforward, well designed valve amplifier, built like a tank, under-run to extend valve life and of very sound basic design. It has an excellent specification and offers usefully more power than many rivals. But of course, valve amplifiers are all about sound quality, something in which they vary widely. It has to be in this area that final value judgements are made and Eric describes his experiences in the main body of the review. NK