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Our ESL Input Transformers (Overview)

Don't Be Fooled by others that say they have a full range Electrostatic step-up Transformer

One of  the most important factor in a SINGLE ESL panel design is the esl step-up transformer which - at best - can only produce SEVEN usable octaves of flat frequency response. The transformer designer may choose which of the seven octaves he wants to build for. 
Our Model 2.1 and 3.1 ESL have a usable frequency response of 175 Hz to 20 kHz with the M299B step-up transformer and crossover. Both models could be used down to 50hz with a higher turns step-up transformer say about 200:1 ratio but this step-up transformer would then only be able to produce up to 6khz in frequency response. I have personally bought both EI and
Toroidal ESL transformers that cost up to $300 each, and have machine wound many a transformer. I have also measured and used over a hundred step-up transformers and NONE with a single output winding will produce seven or more octaves of flat response. Their only one way I know of (if you have another let me know) to build a full range ESL you must use two step-up transformers or one transformer with two secondary winding one for bass (about 200:1 ratio) and the other for midrange and treble panels (at least 50:1 ratio) for a full range ESL. Next the ESL and or speaker baffle have to be wide due to dipole cancellation (24 inches or wider or the sides folded back) to go below 100hz the laws of physics just can't be cheated.  
There are many more factors that that goes into each ESL design but the two mentioned above are most important ones to
start with.


Electrostatic Transformers-Esthetics
We have also paid close attention to our ESL transformer. Our units are manufactured with high grade M6 laminations and machine wound with high quality pure copper wire. The core is varnished and oven baked to ensure quiet operation-even at high ambient temperatures.

We have our ESL step-up transformers custom wound to our specs, we are constantly improving and tweaking their performance. The ESL transformer is one of the most critical components in an electrostatic loudspeaker. Our transformers are of EI the best M6 laminated design. We can offer custom Toroidal designs and are about three times the cost.
Most importantly, our designs are "ear tested".  After a new design has passed extensive testing, it's got to sound good too, before we will put it on the market! From Bach to rock, our ESL step-up transformer maybe for you.

 Our Interleaved Windings
The reason for our sparkling high frequency performance is the use of interleaved windings between the primary and secondary. All windings are machine wound with high quality pure copper wire. All models include multiple interleaved windings to maximize high frequency response. 

Turns Ratio
Our ESL step-up transformers will improve the output efficiency of your ESL. The M299b transformer with a 100:1 ratio will have 6-dB more output then the M99 with a 50:1 ratio and 9 more dB for the M399 transformer. Based on a flat frequency response from 100 Hz to around 10 kHz and 1000 pf load (Model 2.1 12"x48" ESL panel) above that range they will have about the same output efficiency.

Audiophile Electrostatic Step-up Transformers

M299B ESL step-up transformer 100:1turns ratio 1.75" M6 core $98.00 each
3.25"-d x 3"-w x 2.5"-h

The M299B has a 100:1 turns ratio, which is best for ESLs Designed for mid/high band, can be used down to 150 Hz crossover. Rated at 4500 volts maximum output. Electrostatic loudspeakers require high voltages on their stators to move the charged membrane. Therefore a step-up transformer is needed to convert low amplifier output voltage into the high voltage used in electrostatic loudspeakers. The transformers are designed for impedance matching to drive a electrostatic panels capacitive load used for mid size ESL panels with up to 60 mills stator to diaphragm spacing.

M399 ESL step-up transformer 125:1 2.5" turns ratio 2.5" M6 core $125.00 each

4"-d x 3"-w x 2.5"-h

The M399B has a 125:1 turns ratio, which is best for ESLs Designed for lower mid/high band, can be used down to 75 Hz crossover. Rated at 4500 volts maximum output. Electrostatic loudspeakers require high voltages on their stators to move the charged membrane. Therefore a step-up transformer is needed to convert low amplifier output voltage into the high voltage used in electrostatic loudspeakers. The transformers are designed for impedance matching to drive a electrostatic panels capacitive load. Great for large size ESL panels with up to 125 mills stator to diaphragm spacing or bass panels .

 

 
New M99B ESL step-up transformer 50:1 turns ratio $58.00 each

The M99B has a 50:1 turns ratio smaller version of the M299b designed for mid/high band use with a 225 Hz and up crossover, used for smaller ESL panels with 30 to 60 mills stator to diaphragm spacing. Rated at 3500 volts maximum output.

 

2/25/2011

Specifications and design are subject to change without notice
due to our continuous research and development program.
Prices subject to change without notice.
Products made in the USA
2004 Just Real Music