Thanks for your message. I built the cabinet that large (50 liters) because the data sheet shows the frequency response curve in a 50L cabinet. That’s equal to 1.76 cubic feet. I plan to add a port next. Also the cabinet calculators say it can be sealed or ported. It’s my first 100% self designed system so it’s an experimentation on my part. I taught myself about crossovers so it’s evolving. Who knows, I may add a mid range at some point and make a new crossover.
I left enough space to add a second woofer later.
I left enough space to add a second woofer later.
Hmm, based on published specs, sealed is ~ critically damped once some series resistance is factored in; hence vented is a bit too large for optimal tuning and a bit too small for an optimal Fs = Fb tuning, though would tune it to Fs regardless as a reference for fine tuning.
From this, dual drivers will require some form of EQ to flatten them out in room.
From this, dual drivers will require some form of EQ to flatten them out in room.
One step at a time. After I add resistors later this week to equalize the 4 ohm tweeter to the 8 ohm woofer, I’ll have to look at new ways to make improvements. I’m not cutting a hole for the port until I have more listing time sealed. And then I’ll do it such a way that it can be plugged.
I've had some listening time and frankly I'm not sure what to think. Plenty of highs after adding the the 2ohm & 4ohm resistors to the tweeters as my research suggested to bring the SPL down ~ 6db. I have not added a port and probably won't anytime soon. I am mostly playing them without a subwoofer, but have the M&K on standby.
I changed over the AR-9 which I think are my best speakers. They have a lot more lower frequencies.
Now I'm planning to set up the equipment to log the frequency response, so more learning to do.
I changed over the AR-9 which I think are my best speakers. They have a lot more lower frequencies.
Now I'm planning to set up the equipment to log the frequency response, so more learning to do.
@Mez - Just curious how you came up with the crossover design? If you based your XO(crossover) design with an online XO calculator, than I am pretty sure the frequency response of your speaker should be all over the place. I would suggest you pick up a measuring mic, measure the FR of your drivers (mounted in their final position on the cabinet) and run a simulation using program like XSim to design the XO with those measurements. Not to forget, you will also need the impedance response of your drivers for the simulation program to produce a more accurate result.
Yes, I used an on-line xover design. I plan to pick up a microphone and run a simulation program. I can compare it to 3 other quality speakers. I currently have my AR-9 wired up and then I'll switch over the new speakers quickly to understand what my ear hears the difference. I'll do the same with the JBL 4312 and Original Large Advents. Should be enlightening (or more likely confusing).
Initially, they didn't sound like I thought they should. Over time, perhaps they needed breaking-in, they sound much better now. I compared them to the JBL 4312 and I thought they were about on par. I also started moving them around to see if they improved. I spread apart and I was surprised they by the improvement in all aspects. I suppose the initial location in the room caused some frequency cancellation and bad base response.
My current crossover at 2000hz on the 4 ohm tweeter modified to with a resisters to bring down the SPL equal to the woofer seems to work. Still need to set up a microphone to do a frequency response test. Should be interesting.
My current crossover at 2000hz on the 4 ohm tweeter modified to with a resisters to bring down the SPL equal to the woofer seems to work. Still need to set up a microphone to do a frequency response test. Should be interesting.
I gave up on the 4 ohm tweeter and my crossover. Ordered a pair of Morel 8 ohm tweeters and an off the shelf crossover at 2000 hz from Parts Express. Much improvement! I installed REV software and ran some sweeps. Compared the graphs to the Original Large Advents and the JBL 4312 in my living room. These compared very well and the average is actually better than those both of them! I've been listening to them playing a variety of music. Very satisfying. Couldn't be happier!
