Buffer Boss

I've heard this so many times that I just assumed it had to be true. I didn't begin to wonder about it until I saw a thread on TGP where people were arguing about it. Some swore that the tone suck was terrible, while others swore they couldn't hear any tone suck at all.

So what's the truth?

Just for the hell of it, echodeluxe and myself decided to put the 'tone suck theory' to the test in the Wattson shop.

We took a stock Boss OD-3 and powered it from a B&K bench power supply (less than 0.01% ripple on the DC output). We ran a B&K 4012A function generator into the "input" side of the pedal, and set the signal level to a sine wave at 500mV. We ran the output to a Crate V18, switched on but with volume turned all the way down, to provide a proper "load" for the pedal. Then, we hooked up two probes from a Tektronix TDS1001B digital oscilloscope to both the input and output jacks, and plotted the spectrum output of the pedal with frequencies from the function generator from 100Hz to 1700Hz, at 100Hz intervals.

Here's the result:


Code:
Freq In Out
==== == ===
100Hz -15.0dB -15.8dB
200Hz -15.0dB -15.8dB
300Hz -15.0dB -15.8dB
400Hz -15.0dB -15.8dB
500Hz -15.0dB -15.8dB
600Hz -15.0dB -15.8dB
700Hz -15.0dB -15.8dB
800Hz -15.0dB -15.8dB
900Hz -15.0dB -15.8dB
1000Hz -15.0dB -15.8dB
1100Hz -15.0dB -15.8dB
1200Hz -15.0dB -15.8dB
1300Hz -15.0dB -15.8dB
1400Hz -15.0dB -15.8dB
1500Hz -15.0dB -15.8dB
1600Hz -15.0dB -15.8dB
1700Hz -15.0dB -15.8dB

Just in case you're curious, E on the 12th fret of the 6th string is 1318Hz.

So, the only thing we saw was a 0.8dB signal drop across the entire frequency spectrum (which is a few millivolts), but no difference in the frequency response.

Comments?

Attention toutes les Boss n'ont pas le meme buffer !