I finally got this to a point where I can listen to it. 96 1/2" tweeters! It sounds surprisingly good. With another for stereo and lots of EQ it should work well for its intended use.
No. The original plan was 10X SSM3582 amps for midrange and 12X SSM3582 amps for the tweeters, with 22 DSP channels to implement shading and curvature (delay). I've got those 22 channel amps done, but I wasn't convinced that these drivers were high enough quality to justify all the connectors and wiring and amp expense. So, these are just bi-amped. They will go in my wife's greenhouse, and they should work well for that application. There is a short write-up in the current blog at www.audiodevelopers.com.
Since I wasn't sure these drivers would be good enough, I bought Peerless TC6 2" mids and I've been buying 1" AMT diaphragms for the tweeters. Those are the drivers for the next line array, which will be an 8X midrange and 12X tweeter configuration with shading and curvature. The subwoofer will be a ripole, and the mids and tweeters will be dipole. I've got another line array planned, also.
Since I wasn't sure these drivers would be good enough, I bought Peerless TC6 2" mids and I've been buying 1" AMT diaphragms for the tweeters. Those are the drivers for the next line array, which will be an 8X midrange and 12X tweeter configuration with shading and curvature. The subwoofer will be a ripole, and the mids and tweeters will be dipole. I've got another line array planned, also.
I installed the QFN48 USB bridge chip. What a pain. I think I applied a little too much solder paste, and as a result spent some time with a copper braid doing cleanup around the hidden pin pads.
The 5 pin LDO’s went on easily as did the 100uF 10V tantalum caps. Need to order the correct 3x4mm USON8 chip for flash memory.
The 5 pin LDO’s went on easily as did the 100uF 10V tantalum caps. Need to order the correct 3x4mm USON8 chip for flash memory.
On the bench last night is a plank preamp using the Hakuin input stage from the Yarra with a breakout board and having that feed a BTSB to provide a buffered preamp output that is both single ended and balanced. A COTS remote volume pot is used to control volume before the input reaches the Hakuin. For this version, Hakuin is powered by 12v supply feeding an DCDC converter to generate about 27v which then goes to an MOSFET cap multiplier for ripple reduction and slow power in ramp up. Initial testing as a preamp with a bunch of my test tracks is outstanding. Wonderful SE Class A sound signature.
Also on the bench is testing sound quality and operations of the new Vanguard Caldera 12 powered subwoofer. Nice 500w Class D amp with a linear toroidal power supply. Rosewood veneer cabinet. Slot vented alignment. Sounds wonderful.
Also on the bench is testing sound quality and operations of the new Vanguard Caldera 12 powered subwoofer. Nice 500w Class D amp with a linear toroidal power supply. Rosewood veneer cabinet. Slot vented alignment. Sounds wonderful.
I know it's not the right thread.. but I recently switched from rca line level inputs on the caldera 10 sub to high level inputs and it got rid of a slight hum I had. Wiring two class d bridged monos to the high level inputs on the sub was really simple. But there's a lot of conflicting online information about it. Basically, Just connect the red speaker wires ONLY from the amps to the subwoofer. I built spade to banana wires so I could leave the existing speaker wires going to my speakers plugged in and just unscrewed the wbt binding posts slightly and connected the spades. I was advised to try running an rca from my preamps unused input to the subwoofer rca input as a ground wire only, but that added the hum back. I disconnected the rca being used as a ground wire and it's working great!
Sorry about your ground hum issues. Did you get a wire accessory like this to go with your sub? It’s a ground loop breaker. Basically connect the black banana plugs from the high level inputs to the screw on the plate with 10ohm resistor in series. Try this with the RCA. You can’t do this high level from bridged amps since their “ground” will not be at 0v relative to earth ground.
You can also make one using some wire and connectors. The loop goes to the screw and the free ends go to banana black input high level. I repeat, only use with RCA inputs if amps are bridged.
You can also make one using some wire and connectors. The loop goes to the screw and the free ends go to banana black input high level. I repeat, only use with RCA inputs if amps are bridged.
I have been working on subs as well. 12" finished, 15" just starting. Mine are not that great looking, using mostly spare leftover stuff. For garage or spare room just fine.
Attachments
For main system, i use open baffle all the way, including subs. Two 15" woofers per side, still needs eq help. But the quality is there, its worth the trouble.
For other systems, i do not bother. Closed box it is.
The worst sub is car sub. I recently bought dodge durango...don't get me started how bad the sub was. First durango had beats premium system. Ok, i thought that's the reason for terrible boomy one note samba sound.
I returned the car because of other issues, second one comes with 9 speaker premium alpine sound. I thought it will be better. I was wrong. Sounds terrible like first. I believe they use the same speakers, just place different sticker on it in the factory.
One day just for giggles, i will measure that system, it has aux in. But its not priority.
For other systems, i do not bother. Closed box it is.
The worst sub is car sub. I recently bought dodge durango...don't get me started how bad the sub was. First durango had beats premium system. Ok, i thought that's the reason for terrible boomy one note samba sound.
I returned the car because of other issues, second one comes with 9 speaker premium alpine sound. I thought it will be better. I was wrong. Sounds terrible like first. I believe they use the same speakers, just place different sticker on it in the factory.
One day just for giggles, i will measure that system, it has aux in. But its not priority.
You definitely have not heard a properly setup sub woofer in a car, I have built several sound quality audio completion systems with incredible bass, all the superlatives you want to use fit when done right. Loud, well that is part of the fun as well though I never built one to get louder than I needed to match the rest of the system they usually did which I hardly ever cranked it up on.
I hope you get a chance to hear a good sub system in a vehicle or build one, it does not take much, tiny sealed setup, lined up in proper phase, usually EQ required....but still pretty easy and not high cost.
Rick
I hope you get a chance to hear a good sub system in a vehicle or build one, it does not take much, tiny sealed setup, lined up in proper phase, usually EQ required....but still pretty easy and not high cost.
Rick
Even the best systems I have ever heard in a vehicle are below what can be done with a custom install though there are some very high end vehicles that at least should be very fine indeed, be a shame if not. Used to be $2k, now more like $4k, is all that is really needed DIY.
For your situation figuring out a good sub is likely the most critical as it is a foundation piece for all good car audio.
Then again, I have heard many just plain horrid factory systems with lots of speakers, a lot more than needed, just a way to jack up the price putting in crappy gear.
For your situation figuring out a good sub is likely the most critical as it is a foundation piece for all good car audio.
Then again, I have heard many just plain horrid factory systems with lots of speakers, a lot more than needed, just a way to jack up the price putting in crappy gear.
On the bench tonight… I made a thing! 
I got some ‘seconds‘ cabinets from Xrk a while ago. Finally did enough research to find potential driver candidates that would fit* and went headfirst into it this evening.
Elbow grease and MDF dust led to this!
I got some ‘seconds‘ cabinets from Xrk a while ago. Finally did enough research to find potential driver candidates that would fit* and went headfirst into it this evening.
Elbow grease and MDF dust led to this!
- SB16PFCR25-8 MidWoofer
- PT2522C-4 Tweeter
- SB15SFCR-00 Passive radiator
Attachments
Unfortunately, I have my XA 252 on the bench after bonehead mistake. Preamp not on mute, and even worse, selector on phono. Switched on phono pre ( Pearl 3 in this instance) and a transient pop went through the chain and 2 small puffs of resistor smoke came out top vents.
Not much damage, board not fried, 3 resistors burned, BD 140 and BD 139 cooked and one other small transistors, both channels.
Heating up solder station tonight after work. Lesson learned!
Russellc
Not much damage, board not fried, 3 resistors burned, BD 140 and BD 139 cooked and one other small transistors, both channels.
Heating up solder station tonight after work. Lesson learned!
Russellc
Wow, great!On the bench tonight… I made a thing!
I got some ‘seconds‘ cabinets from Xrk a while ago. Finally did enough research to find potential driver candidates that would fit* and went headfirst into it this evening.
Elbow grease and MDF dust led to this!
The cabinets are around 18L internal. Initial listening with passive 1st order crossover at about 2700 Hz is promising! I think I will be able to get somewhere with these…
- SB16PFCR25-8 MidWoofer
- PT2522C-4 Tweeter
- SB15SFCR-00 Passive radiator