Support Forums › Forums › FIR Designer M Support › How to import Magnitude only .txt files? › Reply To: How to import Magnitude only .txt files?
Thank you again for your continued prompt personal attention and support!
Yes, when I’m working through the tabs, I like to keep the “Second View” window open to monitor the final “Show FIR filtered spkr” output curves. Nice feature!
The Mag and Phase outputs in the file you sent to me last night look very similar to my last revision yesterday morning (Noon-ish June 4th here in LR, AR). I do want to explore further your most recent suggestions, please:
– I’m still generally confused by the respective passband delays. I understand the overall “flight time” compensation for EV’s 10′ measurement distance to the front of the speaker cabinet and the -458ms we originally entered in the Import Tab for all three passbands. The EV-provided IIR presets I’ve used for years include delay parameters compensating for the internal horizontal depth of the components LF Mb HF (XVLT 20 15 25 samples) (XVLS 21 0 20 samples). They are slightly different because the “T” is 120×8.5 degrees, the “S” is 90×5 degrees beamwidth. I asked if I leave those in or out – in the file I finished yesterday, they’re out, and from my testing and listening yesterday, it’s all good. But I’ll make the changes today and evaluate.
– It appears you’ve removed 10ms more from the Import Tab “Delay Adjustment” for all three passbands, then reduced the equivalent (values from IIR preset) passbands by 15 samples. What’s the purpose / result / benefit? Will this be an issue for the XVLS preset? XVLS MB is relative time 0 (deepest from the front of both models). It’s important because XVLS and XVLT are used together in vertical line arrays, and part of the reason for this entire adventure is creating new FIR presets which work well in combined arrays. For example, a typical arena hang is 8 or 10 XVLS with 2 or 3 XVLT underneath.
– I didn’t know any better than to leave the FIR Setup Filter Lengths at 200 and 2048 (Powersoft limit). What is the advantage / result of the shortening you did?
– You have a 4th Order APF in the HF, in addition to the Auto Phase. It’s below but slightly overlapping the 1200 low end of the Auto Phase. As far as I can tell, the resulting overall phase response is the same as my existing version (close to 0 down to 370-ish). Why?
Keeping all this in perspective, we’re already at a great improvement in what I’m hearing and measuring compared to the original EV IIR V4.1 from a decade ago. I appreciate your patience and tolerance with my tedious study of the details. Each iteration of question / answer + suggestions, etc. has been a great learning experience for me. Thank you again.
RBT