Not long ago I bought a pair of used Stax ESTA 4U electrostatic speakers. These are 1980s vintage and it is quite difficult to find information about them nowadays. At least, my research through Internet, current Stax dealers or the Stax company itself yielded no substantial results, so buying them was more or less a leap of faith as I was really in the dark before doing so and I could only guess they would be good based in the excellent reputation of this Japanese company.
The Stax company is best known by their excellent electrostatic earphones and amplifiers, but they have also manufactured wonderful electrostatic loudspeakers in the past, at different points in time. The ESTA 4U speakers were released in 1982, and were followed by the “ESTA 4U Extra” in 1983 (have no idea what the differences are). I am not sure either when production was discontinued, but looking at the very limited number of references I have been able to find on the web I don’t think these little speakers were produced in big numbers.
ESTA 4Us are pretty small: 40 x 45 x 9 centimetres, with a weight of about 4.5 Kg per unit. Also, they are self-polarized and their impedance is never too far from 8 ohm, meaning they require no external power from the mains and they can be driven with any small amplifier providing just 20 or 30 watts.
The small size of the ESTA 4Uis what initially attracted me most, as I was looking for quality desktop speakers to replace my Roland DS50 powered monitors (one of them got damaged after a friend borrowed them for a party).
I am totally in love with electrostatic loudspeakers, but there are not so many options if what you are looking for is a small set. I had heard and read about the Magnepan Mini Maggies, which have an excellent reputation but are very expensive too. There is also a cheap desktop electrostatic called IN2UIT, but I was not very convinced by the futuristic arrangement of its panels, which in my view suggests these speakers are meant to be mounted on a wall rather than sit on a desk. So when I came across the Stax ESTA 4U I made up my mind and decided to take that leap of faith, and I am very glad I did.
These speakers are just unbelievably good. They have of course the sound of electrostatic speakers in terms of transparency and naturalness, especially in the mid range. But they do bass too, rich and accurate, and they are a true joy to listen to, in high or low volume. The complex tones of Pat Metheny’s “One Quiet Night” (Warner Bros. 2003) are a tough test for any audio setup, and that is precisely what I am listening at now, and if I close my eyes I would think the musicians are just in front, performing for me in my living room.
So this has been a total success, and I am a happy camper with these two little jewels, though there is a downside to this I don’t want to think too much about. Should they develop a problem I think I would be hardly pushed to find someone who could fix them. Stax dealers no longer support this product, and spare parts must probably be as “unobtanium” as the speakers themselves. So I will just take good care of them and try not to do anything silly with them, and enjoy.
I am presently driving them with a Pro-Ject Stereobox S amplifier (25W). I mostly listen to mp3 music stored in an external hard drive, and I have a Motu Microbook I sound card that does wonders with my computer audio.
My non-portable audio systems, the ones I have to compare the Stax against, are a pair of JBL 4311 and a Revox B750 MKII amp, plus a pair of Braun LE1 electrostatics of recent manufacture (a shop in Germany still makes them) and a Braun CSV 13 tube amp.
I have scanned the instruction manual of the Stax ESTA 4U as well as the technical notes of the kit version (apparently there was one) in case they can be useful to any Stax enthusiast:
Manual:
https://drive.google.com/?hl=es&urp=http://www.google.es/url?sa%3Dt%26rct%3Dj%26q%3D%26esrc%3Ds%26sour&authuser=0#folders/0ByWkf7PV7rISU1EwZENCU3Y1bVE
Technical:
https://drive.google.com/?hl=es&urp=http://www.google.es/url?sa%3Dt%26rct%3Dj%26q%3D%26esrc%3Ds%26sour&authuser=0#folders/0ByWkf7PV7rISU1EwZENCU3Y1bVE
The Stax company is best known by their excellent electrostatic earphones and amplifiers, but they have also manufactured wonderful electrostatic loudspeakers in the past, at different points in time. The ESTA 4U speakers were released in 1982, and were followed by the “ESTA 4U Extra” in 1983 (have no idea what the differences are). I am not sure either when production was discontinued, but looking at the very limited number of references I have been able to find on the web I don’t think these little speakers were produced in big numbers.
ESTA 4Us are pretty small: 40 x 45 x 9 centimetres, with a weight of about 4.5 Kg per unit. Also, they are self-polarized and their impedance is never too far from 8 ohm, meaning they require no external power from the mains and they can be driven with any small amplifier providing just 20 or 30 watts.
The small size of the ESTA 4Uis what initially attracted me most, as I was looking for quality desktop speakers to replace my Roland DS50 powered monitors (one of them got damaged after a friend borrowed them for a party).
I am totally in love with electrostatic loudspeakers, but there are not so many options if what you are looking for is a small set. I had heard and read about the Magnepan Mini Maggies, which have an excellent reputation but are very expensive too. There is also a cheap desktop electrostatic called IN2UIT, but I was not very convinced by the futuristic arrangement of its panels, which in my view suggests these speakers are meant to be mounted on a wall rather than sit on a desk. So when I came across the Stax ESTA 4U I made up my mind and decided to take that leap of faith, and I am very glad I did.
These speakers are just unbelievably good. They have of course the sound of electrostatic speakers in terms of transparency and naturalness, especially in the mid range. But they do bass too, rich and accurate, and they are a true joy to listen to, in high or low volume. The complex tones of Pat Metheny’s “One Quiet Night” (Warner Bros. 2003) are a tough test for any audio setup, and that is precisely what I am listening at now, and if I close my eyes I would think the musicians are just in front, performing for me in my living room.
So this has been a total success, and I am a happy camper with these two little jewels, though there is a downside to this I don’t want to think too much about. Should they develop a problem I think I would be hardly pushed to find someone who could fix them. Stax dealers no longer support this product, and spare parts must probably be as “unobtanium” as the speakers themselves. So I will just take good care of them and try not to do anything silly with them, and enjoy.
I am presently driving them with a Pro-Ject Stereobox S amplifier (25W). I mostly listen to mp3 music stored in an external hard drive, and I have a Motu Microbook I sound card that does wonders with my computer audio.
My non-portable audio systems, the ones I have to compare the Stax against, are a pair of JBL 4311 and a Revox B750 MKII amp, plus a pair of Braun LE1 electrostatics of recent manufacture (a shop in Germany still makes them) and a Braun CSV 13 tube amp.
I have scanned the instruction manual of the Stax ESTA 4U as well as the technical notes of the kit version (apparently there was one) in case they can be useful to any Stax enthusiast:
Manual:
https://drive.google.com/?hl=es&urp=http://www.google.es/url?sa%3Dt%26rct%3Dj%26q%3D%26esrc%3Ds%26sour&authuser=0#folders/0ByWkf7PV7rISU1EwZENCU3Y1bVE
Technical:
https://drive.google.com/?hl=es&urp=http://www.google.es/url?sa%3Dt%26rct%3Dj%26q%3D%26esrc%3Ds%26sour&authuser=0#folders/0ByWkf7PV7rISU1EwZENCU3Y1bVE
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