Story time,
Here I am looking around at my dream shop (cabinetry, wood and metal fab) wondering how to have a little fun on the weekends. I retired mostly from live audio and recording industry about 6 years ago. My new business partner is talking about experiences he had with old school Turbosound and L-acoustic rigs as if he could remember the sound quality compared to modern stuff. I have acquired a little piece of land on which a bunch of audio tech, friends and family gather for fireworks & BBQ when the touring schedules are permitting it. I used to rent an AC generator and a PA system (like Nexo M6 / RS18) for those events but soon find out it was much overkill for most of the time since the jam bands don't even make it to the event sometimes. We end up using 10% of the SPL for ambiance music and karaoke our way through the night. Me and the boys then started messing around with car audio to replace those little JBL Bluetooth mini boom box that are just no fun at all besides for a crowded beach. That's when I found out about little tinny all integrated class D amps from China that run on 24v and have a sub output with adjustable low-pass filter. Since I had zero expectations for the quality of my 35$ by-amp system, I ordered the cheapest 4" car coaxial speakers and 6,5" subwoofer from amazon, watched a couple of car audio subwoofer maker videos and installed WinISD on my computer. That's how I found out how difficult it is to scale a box design for a smaller driver... I ended up with a baffle arrange at 90° and two different ported chambers on each side. One was 42,5L and the other 13 L. I made the ports long and narrow so I could tweak them by jamming wood panels in them to adjust the tuning. My old Smaart program was useless since I was metering the room as much as the box. (Even in a 40' x 40' x 16' garage!) I then checked if the impedance by frequency curve from WinISD was matching my observations and it was off by 3 Hz at both peaks. I took that result for a win even if I lack the knowledge to compare but one thing is for sure, I was hooked to building my own speakers. I then found out that the little port the software told me to put on my boombox top boxes, in relation to the volume, was really giving the boost at around the same frequencies the software was predicting. They don't sound good, but still, they flatten the response. Smaart was helpful in that range. The boombox perform well enough that the boys now want to make me listen to their last recording mix after a couple of beers. I made two other copies for friends who use power tool batteries as PSU and they’re still going strong. I even solve the karaoke thing by using a little 9v premp and mixer.
I now want to learn more about physics, driver parameters and simulation tools so I can figure out more stuff to build and have fun with especially since the fabricating is almost instantaneous for me. (Materials in stock, CAD, CAM, CNC router, sheet metal, paint booth, industrial woodworking tools, cnc lathe & milling, etc.) I feel like a spoiled kid. For now, I'm more into DSP and sound over IP stuff to mess with as for my commercial and PA back ground but I will get to the HIFI stuff eventually I'm sure. My first order of business is a mini line array PA that will replace that first project. I saw 16 channel audio interface with dsp on each of them that are available for less than I toughed possible. To me, that means I can purchase Amp and PSU modules and fiddle my way to the LO-FI mini line array PA or Atmos territory.
Thanks for reading this, I'll be in the subwoofer forum asking about a silly 6,5" driver Mini Paraflex-C box design.
Long live this great forum!
Here I am looking around at my dream shop (cabinetry, wood and metal fab) wondering how to have a little fun on the weekends. I retired mostly from live audio and recording industry about 6 years ago. My new business partner is talking about experiences he had with old school Turbosound and L-acoustic rigs as if he could remember the sound quality compared to modern stuff. I have acquired a little piece of land on which a bunch of audio tech, friends and family gather for fireworks & BBQ when the touring schedules are permitting it. I used to rent an AC generator and a PA system (like Nexo M6 / RS18) for those events but soon find out it was much overkill for most of the time since the jam bands don't even make it to the event sometimes. We end up using 10% of the SPL for ambiance music and karaoke our way through the night. Me and the boys then started messing around with car audio to replace those little JBL Bluetooth mini boom box that are just no fun at all besides for a crowded beach. That's when I found out about little tinny all integrated class D amps from China that run on 24v and have a sub output with adjustable low-pass filter. Since I had zero expectations for the quality of my 35$ by-amp system, I ordered the cheapest 4" car coaxial speakers and 6,5" subwoofer from amazon, watched a couple of car audio subwoofer maker videos and installed WinISD on my computer. That's how I found out how difficult it is to scale a box design for a smaller driver... I ended up with a baffle arrange at 90° and two different ported chambers on each side. One was 42,5L and the other 13 L. I made the ports long and narrow so I could tweak them by jamming wood panels in them to adjust the tuning. My old Smaart program was useless since I was metering the room as much as the box. (Even in a 40' x 40' x 16' garage!) I then checked if the impedance by frequency curve from WinISD was matching my observations and it was off by 3 Hz at both peaks. I took that result for a win even if I lack the knowledge to compare but one thing is for sure, I was hooked to building my own speakers. I then found out that the little port the software told me to put on my boombox top boxes, in relation to the volume, was really giving the boost at around the same frequencies the software was predicting. They don't sound good, but still, they flatten the response. Smaart was helpful in that range. The boombox perform well enough that the boys now want to make me listen to their last recording mix after a couple of beers. I made two other copies for friends who use power tool batteries as PSU and they’re still going strong. I even solve the karaoke thing by using a little 9v premp and mixer.
I now want to learn more about physics, driver parameters and simulation tools so I can figure out more stuff to build and have fun with especially since the fabricating is almost instantaneous for me. (Materials in stock, CAD, CAM, CNC router, sheet metal, paint booth, industrial woodworking tools, cnc lathe & milling, etc.) I feel like a spoiled kid. For now, I'm more into DSP and sound over IP stuff to mess with as for my commercial and PA back ground but I will get to the HIFI stuff eventually I'm sure. My first order of business is a mini line array PA that will replace that first project. I saw 16 channel audio interface with dsp on each of them that are available for less than I toughed possible. To me, that means I can purchase Amp and PSU modules and fiddle my way to the LO-FI mini line array PA or Atmos territory.
Thanks for reading this, I'll be in the subwoofer forum asking about a silly 6,5" driver Mini Paraflex-C box design.
Long live this great forum!
