Remember when postwar Japanese products went from cheap
postwar junk to cutting-edge craftsmanship? Unless your
hair is pretty grey, you probably don’t. Japanese products, especially from smaller companies, gradually became known for uncompromising excellence. Then came the competition from industries in Taiwan, then Hong Kong, which had their own traditions.
And now South Korea. The Koreans began with cheap cars that would (mercifully) rust out before their engines could leave you stranded, but then became serious competitors for even the Japanese, and now they have the Germans in their sights. Could it be long before high-end audio found a place in Korea? It now appears that some of the uncompromising traditions of discipline and excellence that permeate Japan have spread beyond the Land of the Rising Sun.
Though Allnic is not exactly giving this preamplifier away, it is nonetheless its “budget” model, a lower-cost version of its L-3000 flagship. It’s a tube preamp, using a pair of D3a pentodes (commonly used in radio-frequency circuits rather than audio gear), plus a 7233 and a 6485 used for voltage regulation. That wouldn’t appear to be a very high tube count, but no more gain is needed because the outputs come not from an active buffer but from a pair of transformers.
Nowadays, audio transformers are mostly found in tube power amps, and that’s because it’s difficult (but not impossible) to match high impedance output tubes to a low-impedance loudspeaker. Even so, the transformer is often the weak spot in a tube power amp, even an expensive one, because the high level of craftsmanship required to make a good transformer is increasingly rare.
And that’s where Allnic’s experience comes in. Company founder Kang Su Park knows how to build transformers, as he has demonstrated before, and he winds his own by hand. You may recall that we reviewed his AUT-2000 phono step-up transformer in UHF No. 87, and found it to be the best we had heard in… well, decades. A transformer buffer can provide a much more constant impedance curve, at (theoretically) low distortion. There is an added advantage too.
As noted, using transformers means less gain is needed from the active circuits. Gain is never free; it is accompanied by noise and distortion. Less gain means less crud too.
The L-1500’s front panel has buttons for selecting the five inputs (labelled Line 1, Line 2, etc.), as does the remote control. Look at the rear panel, however, and you’ll see that only three of them can be used with unbalanced sources, at least unless you find an adapter…always a compromise. Another way to put it is that only two of the inputs can be used with balanced sources. The front panel has buttons for power (which can shut it down completely) but also for putting the circuit to sleep, with the tubes kept warm but not in actual operation. Also on the front panel is a small round meter labelled “current.” It has no graduations, and is merely intended to warn you when the circuit is outside its operating parameters, for instance if a tube has gone out.
There are two sets of outputs, also confusingly labelled Line 1 and Line 2, one set balanced and the other unbalanced. The “record out” jacks (there is no tape loop) are strictly balanced. If you’ll be using them for recording with a computer, you’ll probably need an adapter, because even semi-pro audio interfaces have unbalanced line inputs.
There is a rear panel switch for absolute
phase, and we were both surprised and pleased to see it. Why does this
matter? Because, on a good recording, you want the leading edge of a wave to come forward toward you, not back. But not all recordings are phase-accurate, and a phase switch can therefore correct for errors. We think it should be on the remote control, not the rear panel. As it is, you’ll find it useful only if your power amplifier inverts phase, as some do. It could do more, though, and we think Allnic has missed an opportunity.
You can probably guess that Kang Su Park has not put a carbon potentiometer into his beautiful unit to serve as a volume control. The control is actually a quality switch with an array of fixed precision resistors. That is superior on a number of levels. Not only does it contribute less noise and distortion, but it eliminates volume differences between the channel as you adjust the volume up or down.
Since the L-1500 is a tube preamplifier, we put it up against our own tube preamp, the Copland CTA-305 that is in our Alpha room. The Copland costs half the price of the Allnic, but we’ve always considered it a terrific bargain, able to keep up with much more expensive preamplifiers. Could it keep up with this one?
We did the comparison with five selected recordings, all of them high-resolution, played from our Linn Unidisk 1.1 Player. We kept both preamplifiers warmed up throughout, and we even avoided switching off our Moon W-5LE power amplifier, so there would be no unwelcome variables in our listening session. This is done by disconnecting the speakers while interconnects are being switched around. Of course we used the same interconnects on both preamplifiers.
We began with a perennial choral favorite, Now the Green Blade Riseth
(PRSACD9093), a superb recording which, in all of its incarnations, throws up a convincing image with illusions of breadth and depth. With both preamplifiers, it sounded impressive.
Yet there was a difference. Both Toby and Gerard noted a change in tone, and of color. What was going on? Were we actually hearing an improvement, or some sort of artifact? Toby scored the difference as a definite improvement.
“Even at the start, before the music begins, the near silence was clearer,” he
said. “I liked the separation of voices better, and the color of the male voices
too. But separation doesn’t mean sounding as though the different voices had
been recorded separately. On the contrary, there’s a natural harmonic blend
among them.” A subtle difference? So far, yes.
Perhaps a high-energy organ recording would shake things up. We listened to the famous Bach Toccata and Fugue in D Minor from the Organ Treasures SACD (Opus 3 CD22031). This is a rich, detailed recording, and of course both preamplifiers reproduced it that way. The smaller pipes were especially clear, with very good articulation but without excess. When the big pipes came in they were almost scary, but throughout we could follow Bach’s distinctive melodic line.
Indeed, Toby thought the piece had seemed shorter with the Allnic, always a good sign. “The pattern in the ‘fluttering’ of the small pipes was clearer,” he said, “and I loved the ‘snore’ of the big pipes.”
What could be more challenging than the Bach organ? How about a piano and a full orchestra? We listened to the first movement of Rachmaninoff’s familiar Piano Concerto No. 2 on a Pentatone 24-bit/96 kHz DVD.
The Allnic preamplifier, it was becoming clear, puts a lot of energy into the bottom end. The opening piano chords, from the extreme left end of the keyboard, were particularly resonant. “The orchestra has more body and energy too,” said Gerard, “and I think that’s due to the power in the bass.” Too much? Albert thought it sometimes was, though he noted that the piano was never less than excellent. Individual orchestral instruments were more in evidence…not always to their advantage!
Once again it was Toby who was especially enthusiastic. He blamed
the sometimes overwhelming kettle drums on the recording rather than
the preamplifier, and he thought the Allnic preamplifier transformed the music into something more than mere neo-Romantic kitsch. “The entry and withdrawal of the orchestral swell is more evident,” he said, “with a shorter period. I followed the conductor’s intent better. I also followed the bass line for piano and double basses better.”
We moved on from these three classical pieces to a jazz song: Jen Chapin singing Stevie Wonder’s You Haven’t Done Nothin’ (Chesky SACD347). This disc is one of the most realistic we have ever heard, and considering the richness of our LP collection that’s saying something! The arrangement is simple enough: Chapin herself in the centre, Chris Cheek’s sax on the left, and Stephan Crump’s thundering bass on the right. Oh…and Stevie Wonder’s genius throughout.
This recording offers a good system a lot of scope, and we were unanimous that
the Allnic was showing itself to be clearly superior. We’ve already noted that it lets
through a lot of bass energy, and so you can imagine what it did with Crump’s
bass. It also let us hear something that we had certainly heard but not truly focused
on before, that the bassist was muttering during the piece. But he wasn’t merely
muttering, he was counting the beats! There was more, much more. Chapin’s
voice was especially powerful, and the sense that she was really there in
the room with us — already convincing—only grew in plausibility. The
saxophone, which was downright erotic in its texture, was “reedier” with the Allnic. The image, which is so strong that probably no system could obliterate it totally, was broader and added even more to the total illusion of presence. Terrific!
We had one more jazz piece, one we have often used in our reviews, in part because it’s so much fun to listen to:
Comes Love from the Opus 3 Showcase album (CD21000). There’s lots going on during this lively piece, and we’ve heard it fall apart even with some rather expensive systems.
Not this time. It sounded glorious with our reference preamp, but the Allnic added to the fun, and we all commented on it.
The sousaphone — a kind of tuba adapted for use by a marching band —plays way down in the lowest part of its register, and we anticipated that the Allnic would reinforce it. Well, it did do that, as it had done earlier with the large organ pipes, but the extra weight might easily have covered up the sense that the sousaphone player is having the time of his life and can barely keep from laughing. It didn’t, and the good humor was clearly contagious. Kenny Davern’s clarinet was richer too, as well as rounder, with more substance. All that goodness with no down side!
A good preamplifier, this, but we’re anticipating that some readers might wonder whether a preamplifier needs to cost this sort of money to get the job done. A preamp needs far less gain than a power amplifier, say, and so its job should be easier, or so you’d think. Indeed, the difference in signal level between input and output is minimal, which is why it’s possible to make a passive preamp… actually not a preamplifier at all, made up merely of switches and a volume control. If a preamp needs to provide gain at all, it’s so that its volume control can throw some of it away, and thus provide a reserve of energy for low-level program material.
Yet passive preamps don’t sound as good as the best active preamps, much as we’ve struggled to prove the contrary. At the same time, an active (i.e. amplifying) circuit like that of a preamplifier needs to handle a very small, and therefore fragile, signal.
How small is it? A typical preamp may have an output of perhaps 3 volts, which doesn’t sound small at all, but that’s the maximum value. If we assume that the music signal has a dynamic range of 80 dB, which is by no means unreasonable, it must then be able to reproduce a signal as small as 0.0003 volt. Yes, that’s 0.3 millivolts, the output of a low-impedance moving coil phono cartridge!
Not many manufacturers would dare to stake their reputations on transformers like the ones in the L-1500, because making such a transformer is a job for a craftsman, not a factory assembly line. That too explains the relatively high price of this product. Audio design is science, sure enough, but it is also an art.
We can’t tell you whether this is the amount of money you should spend for a preamplifier. What we can tell you is what you’ll hear if you do.