Here are some other ways to potentially improve the sound quality of DML speakers besides just adjusting the exciter size:
- Panel Material Selection
- Choose a stiff, well-damped material like aluminum or acrylic for smooth frequency response[1].
- Panel Thickness
- Moderate thickness around 0.5-0.8in provides a good balance of sound quality and efficiency[2].
- Panel Shaping
- Rounded edges and proper aspect ratio improve dispersion and frequency response[3].
- Exciter Type
- Use quality exciters designed specifically for DML use, not just general transducers[4].
- Exciter Placement
- Careful placement based on panel modal analysis improves excitation[1].
- Boundary Conditions
- Free, clamped, or simply supported edges change modal behavior[5].
- Passive Radiators
- Strategically placed passive radiators can improve bass response[6].
- Equalization
- DSP correction helps smooth inherent panel resonance peaks and nulls.
- Enclosure Backing
- A rear enclosure increases low frequency output and provides damping.
- Room Placement
- Careful placement can help mitigate problematic room modes.
So in summary, factors like panel design, exciter selection and placement, boundary conditions, equalization, and room interaction can all significantly affect the sound quality of DML speakers. A holistic design approach is needed.
Citations:
[1] https://projectgallery.parts-express.com/speaker-projects/dml-speakers-with-equalization/
[2] https://www.reddit.com/r/DMLspeakers/comments/r0jwmk/dml_sound_quality/
[3] https://www.avsforum.com/threads/dml-build-w-exciters-doesnt-sound-good.3273889/
[4] https://www.diyaudio.com/community/threads/a-study-of-dmls-as-a-full-range-speaker.272576/page-162
[5] https://www.thegearpage.net/board/index.php
[6] https://www.instructables.com/Plywood-DML-Speakers/