This is version 2 of the surround speaker experiment, see Styrofoam Surround Speakers with Audio Exciters, as it worked very well I now want a more permanent solution.
This time I am using a 120cm x 40cm x 4mm Forex Foam Board, I have purchased this from posterlounge.co.uk as they have artworks this size, I have selected an abstract piece but they have nice cityscapes and scenes, so worth a look.
Even though this is to be a surround speaker, for the in room sound demo below the speaker is connected to the front speaker connections on the amp to show it working as a full range speaker, again the track is Deep Forest – Sing with the Birds.
And again with Diana Krall – Temptation:
Installation
The board is mounted differently than with the Styrofoam version, I have used 2 hooks attached to the wall with Command tape (5.4 Kg rated), using the corner protectors from the Posterlounge box they created a foam platform that is placed onto the hooks this is so it can be adjusted and moved and removed easily. To stop the board leaning forward 2 pieces of the edge protector (again from the Posterlounge box) are mounted level horizontally to the speakers this stops them touching the wall and the gap acts as a channel to get the cable to the middle conduit. The temporary conduit is the support Posterlounge put around the edge of whole box. Yes, the Posterlounge packaging has been very useful.
Conclusion
Comparing the Forex against the Styrofoam, I must say that in my opinion for music only the Styrofoam is marginally better sounding, this maybe because it is stiffer, but both would need bass reinforcement if used for this purpose.
Used as a surround speaker it integrates very well with the front speakers and creates a nice well balanced surround, my main testing discs were:
Films:
Planet Earth II 4K Bluray (Marine iguana scene, just amazing and exciting)
Sully 4K Bluray (Start sequence)
IT 4K Bluray (just the creepy child singing ‘Oranges and Lemons’ around the speakers at the start and the rainfall is enough)
Gravity 3D Bluray (Initial satellite strike, speech from individual speakers)
Music (5.1):
BT – Electronic Opus Bluray 96Khz lossless 5.1 DTS-MA Mix (whole thing sounds amazing)
This project was to create a discrete surround sound speaker both the Forex and Styrofoam would both work very well for this purpose, so it is down to budget, the Styrofoam (90cm x 30cm) is £6, the Forex artwork (120cm x 40cm) is £55 (I used a discount coupon so was £47).
Hey,
This solution seems really cool, have you pursued this any further? I am considering trying an exciter based setup, and had a few questions/thoughts.
Are you still using the Visaton EX 60 S exciters? Did you consider the Dayton Audio range? I ask, because most of the US guys that are building these seem to be using DAEX25FHE-4 or similar to build Styrofoam panels. On the subject of Styrofoam, I’m pretty sure you were not using Styrofoam in your previous panel. As I understand, the Styrofoam product is XPS, while the panel you are using is EPS. XPS is higher density, and probably a better choice for these DMLs as far as I have read.
I really like this idea of hiding the panels inside artwork, but did you consider other materials than Forex? Posterlounge do prints on 8mm ply, and I have seen other print companies offering 12mm birch ply.
The other thing worth mentioning is positioning of the panel. Visaton have a PDF titled Basic principles of exciter-technology (http://www.visaton.de/downloads/pdf/visaton_exciter_principles.pdf). In this, they mention the following about mounting close to walls:
“If mounted close to a wall, especially the low frequencies cancel out due to the bilateral sound output of the excited
plate. The rearward sound is reflected by the wall and, because of the negative polarity, subtracted from
the front-side sound output. The closer the excited plate is located to a wall, the weaker the sound output at
low frequencies.”
Is this something you have experienced? Have you considered suspending the panel on fishing wire or similar to leave more space from the wall and improve isolation?
Sorry for the wall of text, just sharing the things I have come across while researching these panels. You seem to be the only person in the UK that has written anything about building one of these.
I plan to pick up a pair of Dayton exciters from wallofsound.co.uk, and test them out with a few materials and see how they cope.
Thanks for the comment, hopefully, this answers a few questions:
I used the Visaton exciters mainly due to it only needing a squared piece of VHB tape to try on different surfaces, this soon needed replacing (My coffee table sounded great), I just cut another square of tape the Dayton’s need punched circles of tape. Also, I did not know the wattage required they were reasonably high at 50w.
I bought the exciters before doing much research, there is quite a bit, but my project’s purpose of getting surround sound without damaging the rental property walls, and to be unobtrusive and blend in as much as possible.
I just got any Styrofoam just to see what sort of sound I could get and if it was worth going forward with the project, I did try a high-density foam but they were small, so it was more to do with the width.
I have read the PDF, this was a compromise I was prepared to make, which putting both the left and right on the same panel was also a compromise, it is definitely bassier when moved further from the wall, but watching movies I have set the rears to small so the bass cuts off at 80Hz.
I do plan to try other materials and mounting methods. I already have fishing wire just don’t have a hook that puts it far enough from the wall.