The Tube-Tech EQ 1AM is the mastering version of the version of the Tube-Tech EQ 1A. Whether you're adding overall sheen and polish to a final mic, smoothing out harsh vocals and instruments, or just going for some power and punch, the EQ 1AM provides the exactly results you'd expect from a world-class EQ, and does it effortlessly. Built for mastering, the EQ 1M features stepped rotary switches for accuracy and parameter recall.

Tube-Tech EQ 1AM Full Range Equalizer, First Take:

• One-channel, all-tube based parametric equalizer
• High- and low-cut filters
• 25kHz cut for anti-aliasing filters
• High- and low-cut shelving EQ sections and three overlapping bands with stepped rotary controls for gain and bandwidth

All-Tube Based Parametric EQ
The EQ 1AM has seven EQ sections that can be switched in and out, including high- and low-cut, high and low shelving, and three overlapping bands ranging from 40Hz to 20kHz. Except for the power supply, the EQ unit is all-tube based. Both the input and output stages have fully floating transformers for superior electronic isolation, which results in noise-free, ground-loop immune operation. All voltages (with the exception of the anode voltage at the output stage) are DC stabilized, since any variation in the DC energy when combined with the musical signal would cause distortion. Put simply, the EQ 1AM's DC-stabilized circuits keep the EQ bands free of any unwanted artifacts. EQ is smooth and distortion-free.

High- and Low-Cut Filters
The cut filters are designed with unity gain amplifiers. This is significant since they don't load down the source or draw any current. Therefore, they drive the load as if it were a perfect voltage source. They also eliminate distortion due to overload, crosstalk, and other electromagnetic interference. The low- and high-cut sections include a frequency switch with a choice of six frequencies, a slope switch and an in/out switch. Both the low- and hi-cut filters offer a choice of six frequencies.

25kHz High-Cut for Anti-Aliasing Filters
Of particular interest is the 25kHz high cut setting. Its purpose is to roll off the digital artifacts that can be heard when recording to digital systems when using their onboard converters. As you may know, design engineers use the anti-aliasing filters in digital converters to dump garbage" (digital artifacts) above the audible spectrum (above 20kHz). In use, the 25kHz cut appears to have very little effect on the high-frequency content, however, its effect is very audible when it comes to removing the effects of those artifacts.

High and Low Shelving EQ
The shelving and bell filters (for the three overlapping bands) are designed around two tube operational amplifiers. Tubes can be operated in the overload region without adding objectionable distortion they way op amps and solid state amplifiers do. Due to this extra headroom, although subjective, tubes sound louder and have a better signal-to-noise ratio than transistor amplifiers. This is why the EQ 1A sounds so musical and smooth, even when you boost frequencies in the extreme. The EQ 1AM also offers six frequencies of shelving in both low and high sections, and the same 6dB or 12dB slope per octave, and