measurements

All measurements were taken in a semi treated room using a Smith and Larson Audio WooferTester Pro. The speakers were 1 meter away and on the tweeter axis for the frequency response, impulse, and CSD plots. They measured much better without the grills which was in line with what we heard so all measurements were done with the grills off. A protractor and laser level were used to ensure the measurement angles were precise. The response plots were performed on a 10db scale in order to be in line with what is typically done in the industry.

In Summary, the speakers measured fairly well. There were no obvious frequency response issues other than the limited low end bass and a small dip around 4.5Khz. One thing to note is that I also do a test where I just move the microphone around and watch the response for major fluctuations. The Gracioso's performed very well here with the on and off axis response smoothly changing with no abrupt aberrations. I found that speakers that perform this way tend to have a more natural sense to them, image better, and are easier to place.

The on axis frequency response and phase show a relatively neutral speaker. The dip around 100Hz is a function of the room. I later took the speakers outside to measure and the dip was gone. I wanted to be sure. There was one small flaw here that nobody picked up on which is a dip around 4.5Khz. Note how the phase has a little glitch around that same spot. This could be improved with some better woofer to tweeter integration yet it may be part of why people found them so easy to listen to. The phase is pretty linear and looks typical of a second order system.

At 15 degrees off axis, the response is nearly identical with only minor variations and a slight drop off starting around 5Khz. Off axis is in yellow.

At 30 degrees off axis, the shape of the response is relatively in tact with just a larger drop off on the top end starting around 5Khz and a tiny blip around 2Khz. The on and off axis response matching so closely is one of the reasons these speakers image so well.

At 45 degrees off axis, we have more of the same but with more of a roll off starting at 5Khz and the small narrow dip around 4.5Khz has actually improved so a smoother response. The decent off axis response helped add to the sense of ambiance these speakers produced in my small but relatively dead sounding listening room. It also helps explain why I had to toe them in.

At 60 degrees off axis, the response is seemingly smoother than the on axis response but still keeps much of the original frequency response characteristic.

The impulse response shows that these speakers are not wired in phase and start and stop very quickly. The blip around 3ms into the impulse response is likely a reflection off the floor. A perfect impulse response would be a line straight up and then straight back down to where it started.

The step response looks good except that for the tweeter and woofer being out of phase. A perfect step response should look like a slightly concave right rectangle triangle and can give insights into the time alignment of a speaker. Other than the tweeter being electrically out of phase, the step response looks rather nice.

The CSD plot was taken with the window just wide enough to avoid that large impulse response blip shown earlier which is likely a reflection off of the floor or ceiling. The CSD plot shows no obvious problems like driver ringing or box coloration.

The impedance of the speaker can be considered 8 ohms with only minor lows approaching 7 ohms at 45Hz and 6 ohms at 200Hz. There is a slight rise around 1Khz that might make for a more forward sounding midrange on tube amplifiers but the effect is likely to be subtle as it's only a slight rise. The published sensitivity rating is only 88 dB so low watt SET amps are probably not ideal, but the more than decent impedance curve will be a relatively easy load for any amp to push.