Braces are orange, yes that is the holey brace that connects the 2 drivers together, and acts to brace the ML-TL. F10 mid-30s anechoic.
dave
dave
Thanks very much all, super helpful. I definitely know what I don't know here, so I have a lot to learn. Will start with that! Appreciate the quick and detailed help!
Very best,
Very best,
Is it ideal to build an enclosure and mount drivers and do the frequency response metrics and impedance sweep metrics and then making unique FRD/ZMA data from that to model so that it's exact? I'm thinking of building some basic cabinets and picking up a few drivers, inexpensive ones, to practice and test and then try to do a few crossovers with some guidance.
Very best,
Very best,
Yes, this is a good approach. Pick drivers that have the widest and flattest response and consider aligning electrical filter where the natural falloff is to achieve a higher order filter for price of a lower order o e electrically (fewer components). Use REW and calibrated mic to measure the FRD files. Use software like X-Sim for crossover development. You will also need ti measure impedance for ZMA files. You need to either use two mics to get timing reference or use acoustic interferometry to measure acoustic offset in order to simulated accurately.
Hi,
Thanks; I have a UMIK-1 with REW and I have a Dayton DATS for the impedance. I just haven't used them to make FRD/ZMA files for this purpose, so that will be something new to learn. And of course learning how to measure the FRD in a room appropriately so I'm not just recording the room.
Very best,
Elevate speakers to at least 1m above ground at mic axis and measure at 0.5m distance to reduce floor bounce. Put pillows on floor in front of speaker to further minimize floor bounce. Move away from back or side walls. Set audio signal to 2.0Vrms at the speaker. This now scales with 2.83Vrms at 1.0m. Use separate SPL meter to calibrate microphone at 2.0Vrms.
Thanks; that was the part I don't know about at all, how to send signal at a specific value. Not sure how to set signalt o 2.0Vrms.
Very best,
Hook up AC DMM voltmeter to speaker binding posts with speaker attached. In REW use “Generator” function set to 1kHz sine wave and about -12dB. Adjust preamp or volume knob on amp until DMM reads 2.0V AC (2.0Vrms). When calibrating mic in Calibrate mode, use speaker source white noise and set volume on amp to achieve 2.0Vrms at speaker output terminals. It fluctuates a but do your best. True RMS voltmeters are handy here but normal one works at 1kHz sine wave.
Thanks I will look into this! Duh, I have a multi-meter, I should have known hah.
Very best,
Ultimately, knowing there's lots of compromise, I'm trying to use height to make up for lack of foot print and do something that is fairly taller, like 40 inch (H) x 7 inch (W) x 12 inch (D) as a tower. And if I need more cabinet volume, I can go higher. These are not hard values, but rather lofty goals so that they're easy to integrate into a room with furniture and stuff and fit into a few spaces without too much fuss (thought process, its someone else's day room, not mine).
Was thinking of a full range driver and a transmission line cabinet to be pseudo-full range. No crossover at all needed.
Or, was thinking of the full range driver in its own enclosure within the greater cabinet and the rest of the cabinet could be bass drivers with a very simple crossover and crossover higher to relieve the full range driver, so as others suggested, in that 250hz range.
And again, ultimately goal would be to dig down to 30hz in room. Sealed would be fantastic (in option 2) if it would do that. I realize a TL is going to have a vent of course. I just don't know if a TL could do this without being really huge for these limits. Or if it's better to do a full range driver and bass drivers (and I'm ok with more than one bass driver per tower if needed).
Very best,
Was thinking of a full range driver and a transmission line cabinet to be pseudo-full range. No crossover at all needed.
Or, was thinking of the full range driver in its own enclosure within the greater cabinet and the rest of the cabinet could be bass drivers with a very simple crossover and crossover higher to relieve the full range driver, so as others suggested, in that 250hz range.
And again, ultimately goal would be to dig down to 30hz in room. Sealed would be fantastic (in option 2) if it would do that. I realize a TL is going to have a vent of course. I just don't know if a TL could do this without being really huge for these limits. Or if it's better to do a full range driver and bass drivers (and I'm ok with more than one bass driver per tower if needed).
Very best,
If you don’t want to start from scratch and looking for a well designed ready to build plan - Please look at my 10F/RS225 FAST TL. Superb speaker with nice first order crossover. Many people have built it and it’s one of the best sounding speakers I have heard. Cabinet is about dimensions you seek. 10in W x 16in D x 44in H. Plans and schematics fully available here:
https://www.diyaudio.com/community/threads/10f-8424-rs225-8-fast-waw-ref-monitor.273524/
The RS225-8 cannot be substituted. The full range can be and you have choices. TC9FD, TG9FD, B80, RS100, 10F/8414, as long as about 8ohms and 3.5in with circa 83dB or higher sensitivity.
This speaker needs no subwoofer as it reaches deep down to about 30Hz (-3dB). It is a transient perfect crossover and percussion sounds superb. Here is step response:
https://www.diyaudio.com/community/threads/10f-8424-rs225-8-fast-waw-ref-monitor.273524/
The RS225-8 cannot be substituted. The full range can be and you have choices. TC9FD, TG9FD, B80, RS100, 10F/8414, as long as about 8ohms and 3.5in with circa 83dB or higher sensitivity.
This speaker needs no subwoofer as it reaches deep down to about 30Hz (-3dB). It is a transient perfect crossover and percussion sounds superb. Here is step response:
Thanks, they look great! I have looked at that thread twice now and it may indeed be a direction for me to go! I still want to learn to do the measurements and crossover myself, but it's great to have something tried/true/tested to start with.
Very best,
You should be careful when a microphone claims to be 'calibrated', that is sometimes used to distract you from the USB interface which is a disadvantage when making a crossover.
Putting pillows on the floor doesn't sound like a good idea.
UMIK-1 is available with calibration from third party for a little more. Look for Cross Spectrum Labs.
The UMIK-1 uses a USB interface requires use of acoustic interferometry to get acoustic offset. Uses only 1 mic and does not need a separate mic/preamp ADC to USB converter box.
The UMIK-1 uses a USB interface requires use of acoustic interferometry to get acoustic offset. Uses only 1 mic and does not need a separate mic/preamp ADC to USB converter box.
Hrm,
So the MiniDSP UMIK-1 is not a calibrated microphone with its calibration file? That stinks.
Very best,
So the MiniDSP UMIK-1 is not a calibrated microphone with its calibration file? That stinks.
Very best,
It is calibrated from miniDSP but I have heard that Cross Spectrum Labs is a higher quality calibration. Only adds $20.
Oh? Word of mouth type thing or is there data behind that? Just curious. I imagine I'd have to ship the microphone to them to get a calibration file for it?
Very best,