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Thanks Pano,
The Midbass horn is based on an Edgar style horn running 80 to 250Hz (EVM15L driver) the mids are 4 x celestion 4" drivers on an MEH, 250 to 1100Hz, with a BMS 4550 from 1100Hz up.
I was hoping the test would account for driver sensitivities for me
Cheers,
Rob
(currently getting high on the fumes from the freshly painted basshorns
)
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Thanks for the info Rob, I'll see what I can do.
The test accounts for sensitivity only if used in a passive crossover or no crossover system. The test tones will work fine for knowing your bass and midrange headroom, your BMS driver you might have to do a little figuring on. At a crossover point of 1100, it's still going to see peaks near full scale, and it's the peaks we are worried about.
The test accounts for sensitivity only if used in a passive crossover or no crossover system. The test tones will work fine for knowing your bass and midrange headroom, your BMS driver you might have to do a little figuring on. At a crossover point of 1100, it's still going to see peaks near full scale, and it's the peaks we are worried about.
Yep. I've been looking at my files and seems that peak values for genres like rock, jazz and pop are about 6-8dB lower at 1K than they are in the bass. I will post some graphs later.
Your EV woofer states 93.5dB 1W @ 10 feet, which I figure means 103dB 1watt/1m. That's crazy hot for a woofer. Your BMS compression drivers claim 113dB at the same voltage. Meaning you'd need about 1/3 the voltage on the tweeters to reach the same levels as the bass. The midrange I have no idea.
Any system that efficient is not going to need much power for domestic use. Your compression drivers will be fine with flea power amps. In fact the voltage going to the BMS driver is almost certain to be lower than the voltage coming out of your CD player or DAC. That's how the gain on my horn system was set up.
Your EV woofer states 93.5dB 1W @ 10 feet, which I figure means 103dB 1watt/1m. That's crazy hot for a woofer. Your BMS compression drivers claim 113dB at the same voltage. Meaning you'd need about 1/3 the voltage on the tweeters to reach the same levels as the bass. The midrange I have no idea.
Any system that efficient is not going to need much power for domestic use. Your compression drivers will be fine with flea power amps. In fact the voltage going to the BMS driver is almost certain to be lower than the voltage coming out of your CD player or DAC. That's how the gain on my horn system was set up.
Sounds promising! I think I remember my mids being more sensitive than the bms cd which makes things even better. I'll have to check that when I measure for the crossovers..
Edit..just a thought I could run the same level rew sweep though each driver without changing the amp out put and then try and workout the differences from there.. and then do the sensitivity test later on in room...
Edit..just a thought I could run the same level rew sweep though each driver without changing the amp out put and then try and workout the differences from there.. and then do the sensitivity test later on in room...
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I ran another analysis of music tracks. This time mostly 60-90s rock, about 100 tracks. Below you'll see peak values of the tracks (red) vs average (green). I've smoothed it 1/3 octave.
Average level is about 20dB below peak, which indicates that the recordings are fairly dynamic and not overly compressed. You'll also see that the peak values have a somewhat flatter response than average levels.
For a three-way system with you crossover points, I'd say that if all sections had equal sensitivity, the bass section crossing at 250Hz would need 4-6dB more headroom than the mid and tweeter sections. The tweeter section will certainly see the least overall power thru the voice coil, but down toward 1100 Hz the peak values will be the same as the midrange, so you need just as much headroom to play them clean.
Average level is about 20dB below peak, which indicates that the recordings are fairly dynamic and not overly compressed. You'll also see that the peak values have a somewhat flatter response than average levels.
For a three-way system with you crossover points, I'd say that if all sections had equal sensitivity, the bass section crossing at 250Hz would need 4-6dB more headroom than the mid and tweeter sections. The tweeter section will certainly see the least overall power thru the voice coil, but down toward 1100 Hz the peak values will be the same as the midrange, so you need just as much headroom to play them clean.
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Hi Pano,
Managed to get my midbass horns out in the garden on top of a table with the meh horns sitting on top. I'm a bit frustrated with the measurements (the midrange measured a lot smoother on their own the last time I measured, and the midbass horns measure a lot nicer with a groundplane measurement than up in the air....)
Anyhow, these are the plots for midbass / mid / tweet with no EQ/XO and the exact same signal given to each section.
Looks like the tweeter will be the weak spot once it's EQ'd flat to~10k..
Cheers,
Rob.
Managed to get my midbass horns out in the garden on top of a table with the meh horns sitting on top. I'm a bit frustrated with the measurements (the midrange measured a lot smoother on their own the last time I measured, and the midbass horns measure a lot nicer with a groundplane measurement than up in the air....)
Anyhow, these are the plots for midbass / mid / tweet with no EQ/XO and the exact same signal given to each section.
Looks like the tweeter will be the weak spot once it's EQ'd flat to~10k..
Cheers,
Rob.
Attachments
Hi Pano,
Have started setting up the speakers in room. Only the left channel connected. Played Pink Floyd Comfortably Numb at 2am Party levels and measured the voltages at the speaker terminals with the 2 test tones.
Crossover points are 80Hz and 270Hz on my speakers. I've posted an in room 1/6 octave smoothed response of the setup so far.(I've lowered the tweeters a couple of dB since the measurement but that won't affect the results here..)
I measured the sub/midbass at 120Hz, and the midbass/midrange at 220Hz.
The test tones were quite loud! I thought they'd be quiet....
120Hz : Sub 0.1V, midbass 2.3V
220Hz : midbass 2.26V, midrange 1.18V
Cheers,
Rob.
Have started setting up the speakers in room. Only the left channel connected. Played Pink Floyd Comfortably Numb at 2am Party levels and measured the voltages at the speaker terminals with the 2 test tones.
Crossover points are 80Hz and 270Hz on my speakers. I've posted an in room 1/6 octave smoothed response of the setup so far.(I've lowered the tweeters a couple of dB since the measurement but that won't affect the results here..)
I measured the sub/midbass at 120Hz, and the midbass/midrange at 220Hz.
The test tones were quite loud! I thought they'd be quiet
....120Hz : Sub 0.1V, midbass 2.3V
220Hz : midbass 2.26V, midrange 1.18V
Cheers,
Rob.
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I just measured my Magnepan MG-1b panels at a jolly good listening level and got 11.8 volts. That means I want an amp of at least 140 WPC @ 8 ohms for these. Peaks should be hitting 47 volts.
Can the Yamaha RX-V2700 I have connected to the Magnepans do that? Just can. Anything louder would be clipping the amp.
Can the Yamaha RX-V2700 I have connected to the Magnepans do that? Just can. Anything louder would be clipping the amp.
Hi Pano, a quick look at the RX-V2700 manual makes me think 47v might be asking alot...even if just for peaks.
Hard to make a whole lot out of the specs, but dynamic headroom at 8 ohms is listed at 0.84dB....for whatever that means.
There's also a dynamic wattage rating of 170 into 8... so maybe 37v via that spec...again, for whatever it means..
Hard to make a whole lot out of the specs, but dynamic headroom at 8 ohms is listed at 0.84dB....for whatever that means.
There's also a dynamic wattage rating of 170 into 8... so maybe 37v via that spec...again, for whatever it means..