Soltanus Acoustics Driver Unit Mk2
Introduction:
For many this hobby contains a journey through ever increasing gear quality, in order to enjoy our music.
Most of the time this starts with some modest DACs, Amplifiers and headphones, and then continues by gradually improving single components step by step.
So has it been for me as well until I reached a summit Fi Setup of DAC, Amplifiers and dynamic/planar headphones. Like many others I started eyeing electrostats at this point, but due to their completely different amplification requirements this is often a prohobitively expensive investement.
The headphones themselves are usually really expensive, even among ToTL headphones and in order to do them justice one would want an equally high quality amplifier.
By chance I stumbled upon Soltanus Acoustics and their Electrostatic Driver unit. Oversimplified, such an Energizer is a Transformer in a Box, transforming the low voltage of regular speaker or (resonably powerful) headamps to the high voltage required for Electrostats.
Owning a Raal 1995 Immanis, I knew that a transformer Interface can be very transparent without downsides to sound qualtiy. I was very intrigued by the idea to turn my Feliks Envy 25th Anniversary Edition into a high end amplifier for electrostats. Therefore I decided to contact Zoltan and ask wether a few adjustments to his Driver Unit would be possible, in order to meet my personal requirements.
Zoltan was extremely forthcoming and engaged with all my ideas and requests and even suggested some further improvements of his own. The culmination of all these Ideas ended in what is now known as the
Soltanus Acoustics Driver Unit Mk2.
[Front Side of the Driver unit]
Features:
I want to start with the Feature Set of this Device:
- It offers switchable
Input for Speakertaps and 4 Pin XLR connectors, to easily connect any (reasonably powerful) Headphone and Speakeramp.
- It offers both,
electrostatic and regular dynamic headphone outputs in order to connect any Stax Pro BIAS estats and regular dynmic/planar magnetic headphones.
- Since the Feliks Envy has only limited output power being a SET 300B based tube amp, Zoltan added an
Impedance switch for the Driver unit. This impedance switch halfes the transformation ratio from 1:50 to 1:25. This eases the current requirements of the amplifier and can be helpful for less powerful headphone amplifiers. The only downside is, that you lose some gain in the process. The Feliks Envy however doesn't need it, and can utilize even the low impedance setting.
- Among regular headphones there are also vastly different Sensitivities, and connecting a 100db sensitivity heaphone to a speakeramp, can be quite dangereous. Therefore the Driver unit comes with
3 Attenuation settings. 1 - unattenuated for headphones with 80+ db sensitivity, 2 - 90 db senstivitiy and 3 - 100 db sensitivity. This enables me to use Everything in my collection, from Modhouse Tungsten to Meze Elite directly over the Speakertaps of my T+A PA 2000R.
Essentially this device enabled me to use ANY headphone with both of my Amplifiers (T+A PA 2000R SS amp, Feliks Envy tube amp)
As a bonus I can now also use the attenuation of the Driver unit, to utilize the mid and high gain setting of my Feliks Envy with senstitive headphones.(or with slightly noisy tubes)
[Backside of the Driver Unit]
Zoltan even set the power LED to a color which matches the teal of my T+A Displays, which is a nice bonus.
The Driver unit can also be setup vertically and used as a headphone stand.
[Used as a headphone stand]
Sound:
This section will be very brief.
The device doesn't use much more than ultra high quality Transformers. They offer a large iron cross section in order to avoid saturation on low frequencies. Which is unique compared to the likes of the Mjölnir SRD-7, Woo WEE or iFi iESL.
Especially since Soltanus Acoustics own Euridiche Electrostatic headphones are tremendously power hungry, this was very important. I also bought a pair of Euridiche S (Review to follow soon'ish) to test the Driver unit under the hardest circumstances they should ever encounter. All other Electrostats on the market are easier to drive and therefore should also be handled with ease.
The Driver unit is extremely transparent. I can pickup all the differences between my amplifiers and different tubes. There is no rolloff at the frequency extremes and no characteristic flavor of the unit itself.
Which is exactly what I was hoping for, a device that turns my existing ToTL amplifiers into Amplifiers for all types of headphones.
This unit retails for 2590€ including VAT. While still not cheap, it is a rather cheap way to expand a ToTL Headphone Setup to a ToTL Electrostatic Headphone setup.
I fully recommend this driver unit and Zoltans customer Service in general!
Conclusion:
The
Soltanus Acoustics Driver Unit Mk2 is a versatile and exceptionally engineered device that opens up the world of electrostatics for those who already own top-tier amplifiers. It allows you to transform any powerful speaker or headphone amplifier into a true multi-purpose unit, capable of driving everything from sensitive dynamic headphones to demanding electrostatic models.
I do own both, the Euridiche S is also my unit bought at the same time, no loaner. And I'm also still interested in the CRBN² and wait for the offer from my dealer.