November 2015


Acoustic Signature Thunder Three-Motor Turntable And TA-1000 Tonearm
Thunder turntable with three motors is an amazing bit of analog kit.
Review By Wojciech Pacuła

  If one is looking for an iconic German turntable that embodies the country's precise engineering and perfection, one should consider products of Acoustic Signature as a very strong candidate. This company, founded in 1996 and operated by Mr. Gunther Frohnhoefer, has been developing their offer without rushing things. Still, they do introduce necessary improvements and changes to their products on a regular basis. Within recent years I reviewed few models of their turntables, but none of them was as advanced or as refined and their pricey as the Acoustic Signature Thunder as reviewed here with three motors (€8499 plus €678 for each additional motor). It is a representative of the group of products with a minimum chassis, which is roughly bigger than the platter. It is a non-suspended mass-loader (101 lbs.) with external motors. It sports a resonance optimized chassis and sits on three large, adjustable feet made of ultra-soft aluminum with very good vibration damping properties. The basic version of Acoustic Signature Thunder turntable includes a single motor, single tonearm and no record clamp. There are some quite significant upgrade options. It is possible to equip it with up to three tonearms (9" to 12") and three motors. The AlphaDIG power supply sports three synchronized outputs that allow using three motors. An optional record clamp is also available.

For this review we received a deck with one 10" TA-1000 tonearm and three motors. Additionally, I decided to use a record clamp made by another German company from Berlin, Pathe Wing. The turntable was placed on the top shelf of my Finite Elemente Pagode Edition (another German product) rack and within the system includes two phonostages: RCM Audio Sensor Prelude IC and Amare Musica ASPIRIAA. For record cleaning, as always, I used and ultrasonic AudioDeske machine and yes, you guessed right, this is also a German product. Last but not least, three cartridges were used: my trusted Miyajima Labs Madake and Zero plus the Denon DL-110.

Chassis And Platter
Acoustic Signature's Thunder turntable is a top-performer and I mean not only amongst their product lines, but also compared to other competitors. There are three more costly models in this German manufacturer's portfolio, all of them sporting completely different shape than Thunder. It is also the first model using the latest platter technology called "Silencer Platter 3". The idea was to create a way to dampen the platter's resonance without using any soft plastic material. A 50mm solid turntable platter is made of a very soft alloy and it sports 24 inserts made of brass – one can see them as golden circles on the top of the platter. Manufacturer claims they work best (as vibration dampers) in a critical (for human hearing) area between 400 and 6000 Hz. It is a third generation of this technology – each new one improves a precision of matching the inserts with holes in the platter. Clearance between insert/silencer and a hole is of less than 1/100^th of a mm.

On top of a platter sits a leather mat – something often used for Acoustic Signature's turntables. But to keep their golden silencers visible, the mat sports holes aligning with them. The platter is 50 mm thick and quite heavy at 37 lbs. As one has to place this heavy object over main bearing's shaft, and it fits very tight, it is not such an easy job to do. Acoustic Signature's Thunder 70 mm thick chassis sports a round shape, which is slightly larger than a platter. Together with a platter and three solid feet it constitutes a not very tall but hefty piece of equipment.

This entire structure rests on three large and hefty feet with a diameter of 100 mm. They seem to be a part of the chassis with a small semicircular adjustable elements on the bottom. Since this turntable is really heavy it is important to place it on the flat and hard surface. Note that when placed on wooden shelf/platform it might leave some permanent marks on it. Looking back at Acoustic Signature design history it seems that they focused their efforts on development mainly within the power supply and main bearing area. For the latest and most expensive models it seems that shape and mass of the chassis plays an important role, yet the key elements are the two mentioned above.

Main Bearing, Power Supply And Motor
The main bearing is perhaps the true heart of each turntable and most efforts are invested in this tiny spot where bearing's shaft touches the base of the bearing. Thunder sports the latest Acoustic Signature's development in this area with a material called Prolongation. It's an alloy made of vanadium, titanium and Teflon. It is relatively soft, yet at the same time an extremely durable material that is used at bearing's base. The platter bearing component is manufactured from special hardened and polished steel, with an extremely hard tungsten carbide ball at its base. The bearing housing uses perfectly matched and ‘aged' sinter bronze inserts, which are self-lubricating and therefore maintenance free. All the elements are made with such a great precision and are so perfectly matched that Acoustic Signature guaranties at least 10 years of trouble-free usage.

Acoustic Signature uses a European made synchronous motor with their in-house built motor control called AlphaDIG. Enclosed within a small aluminum box, this quartz precision DSP produces a perfect sine wave at 24VAC to run the motor. This results in a perfectly steady and constant platter rotation. Voltage is delivered to the motor(s) via cable attached to a multi-pin RS-232 socket. In fact, apart from a power inlet, the rear panel sports three such RS-232 sockets. This power supply can be used simultaneously with up to three motors – just as the version under review. The controller sports two push buttons. One turns the power on/off, the other allows user to select proper speed. The former is accompanied by a green LED, the latter by two orange ones for 33.33 and 45 rpm.

As I already mentioned, this deck uses a synchronous motor made by an European manufacturer – which one remains unknown. It is placed in a solid, heavy aluminum housing that is filled with damping material. This housing is placed on a rubber feet – this is the only (soft) decoupling element in the whole design. When three motors are used, each of them uses feet of different height. A large aluminum driving wheel is placed on each motor's shaft – this driving wheels reminded me of ones used by Thorens. Acoustic Signature decided to use a square rubber belt stretched directly over the platter. Motor positioning in standard one-motor setup is standard and in the back on the left hand side. When using three motors, one places them around the deck behind deck's feet. Their axes should form an equilateral triangle. Such positioning stretches belts bit more than manufacturer suggests for a single-motor setup. The deck itself is quite big measuring 440 by 440 mm. Motors extend even further the required surface for this turntable up to the size of 480 by 520 mm. This means that one needs quite a large platform/shelf to accommodate this turntable.

TA-1000 10" Tonearm
One should know that it is possible to use up to three tonearms for this deck. Models like Storm, Challenger and Thunder all come with chassis and tonearm-bases being separate elements joined with a flat, metal element and screwed together with a bolt. This solution allows moving the arm-base closer or further away from the deck so that a 9", 10" or 12'' tonearm can be fitted to it. The actual arm-base takes the same form as the cylinders housing motors. For many years Acoustic Signature used tonearms made by specialized companies like: Rega, SME and others. Since October 2014 they finally offer their own product called TA-1000. It is available in three lengths: 9", 10" and 12" – for a review we received the 10'' one that is most popular in Japan.

Acoustic Signature decided to use precision miniature bearings sourced from a German manufacturer SKF. The tone-arm tube of a fixed diameter along the whole length is made of carbon fibers. In fact there are two tubes, one inside the other joined by three ribs. Such design allowed a small weight combined with a high rigidity. No additional damping elements were required. The internal tube holds cabling made of high purity copper (6N) wires with Teflon insulation. There are two options available – in first of them there is an uninterrupted run of cabling from headshell to RCA plugs (the external part of the cable is 1.5 meters long), in the second option there is a DIN socket in the arm-base which allows to use any interconnect (with proper termination). We have received the latter for the review together with 1877 Phono cable.

TA-1000 does not sport a classic headshell. Instead, there is a flat element screwed to an aluminum ending of the tonearm tube with a single screw. I've seen this solution before as used, for example, within Clearaudio tonearms. One screws the cartridge to the flat element permanently and then moves this whole element forward or back along tonearm's aluminum end for proper setup. It also allows to setup a correct azimuth. It might be a bit more difficult to handle than classic solution but it is doable and once you've done it a few times and thus should not be a problem. The setup is easier because, together with the turntable, one receives a metal protractor to ensure perfect alignment.

The counterweight is made of brass with the typical turn it to move it forward or backwards. The threading is rather small to provide a precise setting. Once the correct tracking force is applied, the counterweight is easily screwed down with three small setscrews. Setting correct VTA is not that simple as it is a classic solution with a clamp holding the base of an arm. The anti-skating is a nice looking classic solution and has a short line and a small weight. In this particular case, this small weight moves inside of an aluminum housing to prevent extensive movement of the weight.

Sound
I think that every vinyl LP fan has his own opinion on how his records should sound like. So in fact the general consensus on the definition of the "right" sound is rather... undefined. This allows a large number of different combinations of sound qualities that, in fact, lead to different outcomes. And yet, I believe, that they all could be equally "right". Many people associate non-suspended mass-loaders with sound rich with heavy bass, sounding also a bit "thud". Compared to such stereotype designs like Linn Sondek LP12, Thorens, and later also Avid's decks seemed to sound very energetic. And while it usually meant a bit less precise and resolving, people still liked them a lot. There are a vast number of such turntables sold and perhaps is the best proof of that. Acoustic Signature's Thunder with three motors sounded totally different than above described stereotype mass-loader. That didn't really come as surprise to me since it wasn't the first Acoustic Signature deck I had a chance to audition. Still, color me quite surprised by the scale of this difference.

The first, quick sonic association I had was with idler decks like Thorens TD 124, Garrard 301, and also the Lenco L75. Listening to the records of Johnny Hartman and Nina Simone, that had just arrived as released by ORG on 45 rpm vinyl I felt shivers going down my spine – literally! It is not me being over-enthusiastic mind you. The key element was a perfect rhythm. Even the SME Model 15, that I had at my disposal at the same time (great deck) could not compare to this Acoustic Signature design in terms of perfect timing. It is not about wow and flutter, as most correct designs don't have problem with that. It is rather about this element that in digital world leads to increased sound density, to making it bit warmer without actually changing its timbre. It is achieved by enriching the sound with abundance of information, by internal "coherence" of this information. Sounds played by Thunder don't "fight" each other or try to get ahead of others. They are simply delivered without paying too much attention to any of them in particular and only together they create something on a new higher level.

Despite what I just wrote, I don't think anybody would call this turntable warm sounding and surely wouldn't call it that. Just as I would never call it bright sounding either. The aforementioned SME as well as TechDAS Air Force Two delivered a brighter sound within my system than Acoustic Signature's three-motor Thunder. I'd rather say that Thunder delivers a sound illuminated from within. It doesn't make sound bright nor harsh, but one can "see" the sound "shining". I think the credit for this should go to this amazing energetic way music is delivered to the listener. The entire listening room seemed to become filled with this energy just as the turntable had some sort of additional power source connected directly to the cartridge.

Both range extremes were extremely precise. Never exaggerated, never to edgy. This was very "personal" and emotional presentation. The very top-end was quite sweet and silky-soft. This is a feature associated with suspended decks and the best representatives of that type of design offered something similar. But they were not able to combine it with this thunderous, amazingly dynamic, plus "hot" bass as delivered by Thunder. Bass was also particularly well differentiated and only top decks such as the TechDAS (One and Two), expensive SMEs (20/13 and 30/13), top Avids and Transrotors were capable of delivering even better performance in this respect by delivering even deeper mid-bass and showing larger phantom images. The German turntable never tried to extend bass beyond its capabilities – it used its ability to maximum but didn't do nothing more than that.

The midrange was very precise and rich. It had nothing to do with the above mentioned stereotype of a "thud/dull" sound of mass-loaders. It was also very important in how Acoustic Signature's Thunder beautifully rendered vocals from 1950's and 1960's records as well as from Polish (mediocre quality) issues from 1980's. A remarkable, well controlled sound that selectivity allowed vocals to be properly presented even if the whole sound of a particular record seemed a bit hazy. This was possible without adding any brightness to the sound. It was like all the vocalists were given a second life.

A separate paragraph for distortions seems to be in order. All vinyl fans are used to them, but the fact remains that they are distortions. There were far fewer ticks and pops with this turntable than with many far expensive competitors. And not only with Miyajima cartridges but also with ZYX ones that were used for auditioning with Thunder. Yes, I could still hear them, especially with older records, but they were never part of the music. It is as though they were a separate thing existing "next to" the music. They did not change the sound of the music itself. This same comment applies to background noise. New issues from RTI, Quality record Pressings, Pallas and others were ultra-silent with a truly black velvet background. This feature of the Acoustic Signature Thunder allowed me to listen to many records than usual. Problems of some less-listened to LPs due to pressing quality-induced fatigue were still there, but they didn't matter anymore as it never held me back from enjoying the music.

Summary
That fabled perfect, ideal audio system and component is a myth. Acoustic Signature's Thunder could perhaps provide a touch better bass extension and the motor could be better shielded. Of course we'd all appreciate a lower price. But I know very well that there are no perfect products so am able to fully appreciate those that are truly good. Bottom line is that I must admit that the Thunder turntable with three motors is an amazing bit of analog kit. It combines the best qualities of idler turntables and mass-loaders. It delivers vivid, dynamic, precise, and rich sound. Such a set of qualities rarely describes a single device. It is quite expensive ticket to high-end audio world, but a real one worth your time and consideration.

Specifications
Type: Vinyl LP record player with three motors
Drive Unit: Synchron motor, electronically regulated, power-decoupled and adjustable
Bearing: Highly precise roller burnished TIDORFOLON bearing
Chassis: Resonance-optimized chassis with 3 adjustable feet.
Platter: Precision made aluminum 5 cm thick, 33 lbs. with 24 Silencer modules.
Speed Range: 33.3 and 45 rpm
Power Supply: 100 to 260V AC
Dimensions: 440 x 440 (DxW in mm)
Weight: 101 lbs.
Color: Black or silver
Price: €8499 with one motor, each additional motor adds €678

Tonearm
9 inch: €1298
10 inch: €1349
12 inch: €1399
Silver Internal Wire: €250
Available as direct wire version or with 5 pin plug.

Company Information
AS-Distribution GmbH
Salacher Str. 88 
D-73054 Eislingen
Germany

Voice: 71 613-898-135
Fax: 71 613-898-137
E-mail: info@as-distribution.de
Website: www.AS-Distribution.de