I have used these for years with my 8 Watt per channel SET 300B tube amp and they are amazing. This is a second pair that I had running subwoofers. I have not noticed much difference with the powered subs, so I emailed Paul Spetlz and he said they would not make much difference. So I am selling this pair. I am keeping the pair that are in line with my Omega Maxhemp speakers, and they really make a difference. Bass is "tighter" better defined and integrated with the subs. Detail and transparency are improved, and there is better definition in instrument location. Things seem just a bit "faster" in general. In short, they really do work. They sell for $540 new per pair shipped and are really heavy (insured shipping will run about $70). Here is a brief description from the zeroimpedance website:
The "Naked" ZERO-Autoformers have 18 inch (46cm) leads of 12 gauge copper wire, along with spade terminals attached on each lead. For those with mono block amplifiers, the 36 inch (92cm) total span should be long enough to connect directly between the amp and speaker. For those who need longer wires, utilize existing speaker cables connected to the ZERO-Autoformers with a set of binding posts. The price of the "Naked" ZERO-Autoformers is $540/pair. Zeros, the original toroidal autoformer, and all have the ability to multiply a speakers impedance by 2x, 3x, or 4x. For example, the ZERO can transform a 4 ohm speaker into an 8 ohm, 12 ohm, or 16 ohm speaker depending on which two of four leads/connections are connected to the amplifier. They are very helpful in matching speakers to amplifiers, even amplifiers that already have a variety of output taps available realize benefits.
Please note that two of the spade connectors on each autoformer are missing one tab (see images). They can be used this way, or the spade connectors can be replaced easily.
A
note about international shipping. Since it is very difficult to
accurately estimate shipping in advance, I list the maximum amount that a
buyer would pay. If shipping is less, I refund the over payment as
soon as I have printed a shipping label.
Images are part of the description.
OFFERS WELCOME!!! Questions welcome too. Thanks for looking, Mark