“The tubular case is metal and feels rugged enough to drive a truck over it without damage (I didn’t try this, however!). It weighs less than three ounces (80 grams) and is under four inches (about 96 mm) long. The finish is excellent, pins are gold plated, mic lock works smoothly, and it feels very solid overall.”
GAIN & IMPEDANCE
“I found the gain of my Dynamite to be 28.9 dB at 1 kHz and it varied only +/- 0.05dB over a frequency range of 10 Hz to 24 kHz. That is flat! I measured the same gain with a direct signal measurement using Room EQ Wizard, and using a ribbon mic with an output impedance of 300 Ohms on a mic stand a few inches from a speaker. I did not (and can not) test it out to 120 kHz, but have no need for such bandwidth! Phase response was also text book flat - essentially zero degrees from 10 Hz to 24 kHz, meaning no signal inversion and no phase shifting."
“Using a variable input impedance preamp, I found the gain dropped only 0.1dB when driving a 300 Ohm load, and above that, up to a 3 k Ohm load, gain was always 28.9 dB. Loading it with 150 Ohms reduced the gain by about 3 dB, but most mic preamps run 300 Ohms to 3 k Ohms.”
“Distortion was difficult to measure since using an input in the low millivolt range did not produce harmonics above the noise level. To get a clean reading I had to use over ten millivolts and found total harmonic distortion appears to be composed primarily of the second harmonic with a smaller level of third harmonic. Fourth and higher harmonics are much lower and contribute nothing really measurable to the total. THD measured from about 0.1% with 10-15 mV rms input (equivalent to about 110 dB SPL into an SM58) up to 0.2% at the highest level I tested (equivalent to about 125 dB SPL into an SM58). And the distortion level is even across the audio frequency range. This is good distortion performance, certainly below the threshold of human hearing.“
THE BOTTOM LINE
“If you are looking for a solid, high gain signal booster that almost meets the old engineering goal of a “wire with gain”, I’d say sE Electronics have created it. There are other mic boosters available, and I admit I haven’t tested any of them (be glad to do so if they send me one to test!). From what I’ve heard and read, other brands have higher output impedance (gain not as stable with changing load) and higher noise levels, but some have variable input impedance (to affect mic tonality) if that is of interest, and may be suited for your needs. For me, the Dynamite fits the bill.”