Product name: Mummy
Manufacturer: hORNS by Auto-Tech
UK Distributor: GPoint-Audio
Cost: £4000. (Currency conversion)
Reviewer: Mike Cox - TNT UK
Reviewed: July, 2015
Are you bored with conventional speakers in rectangular wooden boxes? If so, you need look no further. The hORNS.PL Mummy by AutoTech could never be thought of as conventional in looks. The Mummy uses a moulded fibreglass composite outer shell with internal, multi-layer damping, to reduce colouration to a minimum. The Mummy is more efficient than the average speaker (96dB/1W/m), and presents a 8 Ohm load, suitable for almost any amplifier from low power valves, to conventional solid state designs. The Mummy uses a single wire connection and they weigh 30Kg each, a challenging lift up my two flights of stairs.
The bass driver is a 12", low moving mass design with powerful magnets designed to give "amazing" transient reproduction. The cabinet is reflex loaded with two rear ports so hopefully the bass is reasonably deep, as well as the speaker being efficient. The upper frequencies are handled by a 1" compression tweeter matched to a unique wave guide specially developed for the Mummy. The wave guide looks similar to a JMLC or spherical horn. The Mummy is available in a range of standard colours, the review pair being in green (looks like British racing green to my eyes). The speakers come with magnetically attached covers for the bass drivers, these were removed for the review.
Mummy up close
I started listening to the Mummies using the MySound Cube amplifiers, a valve amplifier using EL84s. This combination worked well together and looked like no other audio setup I have ever experienced! If you have not already seen the Cubes review look here:- My Sound Cubes. I also tried my Leak Stereo 50 and Stereo 20 and in the end settled on the integrated 300B SET amp I purchased cheaply from China about 8 years ago. This amplifier uses ECC83 and ECC82 for voltage gain and driver duties with the single 300B as the output tube. Since acquiring the amp I have replaced all the valves and upgraded the PSU and coupling caps.
The low powered single ended triode valve amplifiers have a reputation for soft and slow bass. The amplifier output impedance is high in comparison to a solid state amplifier and with the wrong speakers can produce a soft and imprecise bass. I was most interested to find out how well the Mummy worked with my 300B amplifier. When speakers are designed for efficiency a common limitation is bandwidth. The bass is usually where the bandwidth is limited; you can have efficiency or deep bass, but not both in my experience. This is also my first experience of a horn loaded compression driver in a commercially produce speaker, so there is a lot to explore with the Mummy.
I have spent a lot of time with these speakers, driving them with various amplifiers in my collection. They all worked very well, even the modern class D models. The Mummies are very amplifier friendly, the 300B amplifier was able operate without concern for lack of power. The bass with the 300B amplifier is by far the best I have heard from this type of amplifier. The sound in the bass is detailed and well balanced with the output from the horn. Playing Dave Brubeck and the album Ken Burns Jazz, some live recordings from the early 1950s, the result is wonderfully balanced. All the instruments have equal weight with the rhythm just about what you would expect.
Mummy rear view showing the dual reflex ports
With a lot of speakers, when the volume is turned down the sound can collapse and the listening experience is much less interesting. Using the Mummy with the 300B amplifier, the balance and soundstage remain the same whatever the volume, so you can enjoy that late night music session without annoying the neighbours. With a modern, well produced recording, such as David Watkin playing the Bach Cello Suites on the Resonus Classics label and downloaded as a 24bit 96kHz FLAC format from HDTracks, the Mummies allow the music to really shine. The soundstage is wide and deep, with the rich tone of the cello well presented.
At the moment, I have a new turntable setup, with my regular Garrard 401 & Rega RB1000 combination fitted with a Rega Carbon moving magnet cartridge (bargain of the century). The phono stage is an Encore 7 Eggshell PS-5 and this front end, through the Mummies works very well. The Rega Cabron cartridge can sound a bit course at times, but the PS-5 allows it to sound good most of the time, and with the Mummies, we have a good combination that is well balanced. Spinning up the "Alison Krauss & Union Station" album "So long so wrong" on MFSL produced 180g vinyl, the music had all the vitality and dynamics with a mesmerising vocal from Alison Krauss. What was most surprising was the apparent extra octave of bass, even at low volumes.
The Mummies sound beautiful with the right setup, they are very revealing of source quality. You will need a quality digital source and amplifier to allow the Mummies to show their true capabilities. I have noticed recently that digital sources have been closing up on vinyl, the availability of well produced high definition recordings, with DACs able to handle the quality has taken digital media up a level. With the Mummies, good valve amplifier and decent vinyl front end the gap to digital sources has again widened in my experience.
In my attempt at building a speaker with a compression driver and horn plus large bass driver using the Reckhorn DSP-6 as the digital crossover I found the horn projected the sound stage forward from the speaker. It was as if the musicians were almost sitting on your lap. With the Mummies the sound stage feels much more natural, it spreads beyond the width of the speakers and with the right material out into the distance behind the speakers.
The marketing material for the Mummies claim "amazing transient reproduction" and with the right material this is the case. The kick drum on Roberta Flack's 1973 album "Killing Me Softly" had a good slam. With the "Buenavista Social Club" album the complex percussion rhythms come across as very life like.
If you are not familiar with a compression driver feeding a horn then you will notice it has its own, different presentation from regular dome tweeters and mid range drivers. If you use low power valve amplifiers you should audition the Mummies, they really do allow the amplifier to deliver its best results. If you are also a vinyl user then I strongly recommend an audition, they are worth seeking out and travelling that extra mile.
© Copyright 2015 Mike Cox - firstname.lastname@example.org - www.tnt-audio.com