It looks like you shorted the positive outputs with a red wire.
Yeah, you don't want to do that. It's wrong on your drawing, too.
Just cut off that wire.
Just cut off that wire.
OK, on the output side I see (DUH!, I need separate plus-minus for each transducer) the jumper is a short.
What about the input? The jumpers are the right way to get separate feeds to the halves of the crossover. Yes?
What about the input? The jumpers are the right way to get separate feeds to the halves of the crossover. Yes?
The extra output black jumper wire appears to be redundant also, but would not cause an outright malfunction like the red one would.
The input jumpers are both needed to connect both the high and low crossover sections to the input terminals..
The input jumpers are both needed to connect both the high and low crossover sections to the input terminals..
Big Thank You Rayna and Marcel. Got it sorted now. Don't know what I was thinking on the output side. Or that black wire antenna!
This is why my last amplifier build was back in 2015. I no longer can be trusted with high voltage but I thought, "I know, I'll use up those old dusty woofers and what's in the parts bin, how hard could it be?"
Gonna listen to these while I'm waiting for my Ticket To Ride.
This is why my last amplifier build was back in 2015. I no longer can be trusted with high voltage but I thought, "I know, I'll use up those old dusty woofers and what's in the parts bin, how hard could it be?"
Gonna listen to these while I'm waiting for my Ticket To Ride.
That should work. 4th order LR is a really good way to go. To take it to the next level, you might want to load that design into a crossover design program like Xsim, Boxsim or Vituix CAD. You may find that the impedance variation with frequency of the woofer and tweeter will play around with the phase and rolloff of those filters. Adding a few more components to get the impedance of each driver to be flat through the crossover region might get you some improvement. Of course doing that takes a lot of time to make measurements of the individual driver impedance and acoustic output and learn the software. So if it sounds good as is, rock on.
Some tuning by ear perhaps, mainly to attenuate the tweeter as needed, and since the 12" will be light on power at the top end if EQed flat on axis, the tweeter may seem to cut in hard.
The final few furlongs are always the hardest but I got one speaker done and bumped downstairs on the 2 wheeler. Hooked it up to my cheapo Bluetooth rig and, playing off my phone, it sounds darn good. I knew the SB-29 tweeter was quite efficient but the channel balance when paired with the very efficient 4 Pi Pro had voices pretty much in the middle. The big Utah must be in the low to mid-90s.
Tomorrow I'll close up the other box, wrangle it downstairs (Baltic Birch is HEAVY) and have a real listen.
Tomorrow I'll close up the other box, wrangle it downstairs (Baltic Birch is HEAVY) and have a real listen.
The first attempt gave impressive bass and rich mids but the too efficient SB Acoustics SB-29 tweeter cut in hard just as AllenB predicted. I had one 3 dB less efficient Peerless DX-25 left over from a bass guitar speaker build and bought another to try the pair which worked really well. So at least 50% of the treble is still in the parts on hand cheap build category.
The result is what I'm calling "the best darned garage speakers in the land", the fancy flat cut cherry veneer cabinets notwithstanding. My 4 Pis are more 'high end' but the F6 at around 36 Hz of these is very welcome. Thanks to all who helped.
The result is what I'm calling "the best darned garage speakers in the land", the fancy flat cut cherry veneer cabinets notwithstanding. My 4 Pis are more 'high end' but the F6 at around 36 Hz of these is very welcome. Thanks to all who helped.
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Did you put any braces in the box? If not - try some dowels or even pieces of 18mm x 30mm MDF side-to-side / top-to-bottom (allowing for crossover mounting). Will stiffen up those panels.
Rather than change tweeters, you might just buy an L pad and adjust the level. I think you will find the majority of crossovers include an attenuator for the tweeter as it is very often more efficient than the woofer. They are very easy to use. Pick one that matches the impedance of the tweeter & crossover design. https://www.parts-express.com/search?keywords=L pad&order=relevance:desc
Try two resistors to knock down each tweeter. One series (try 2.2R), and one parallel (try 4.7R),
added just before the tweeter.
added just before the tweeter.
Regarding attenuation, this is my view on the subject:
1. The cleanest sound will always be to match drivers to each other.
2. The second best way is to use a fixed resistor network, at least according to a recent test done by Joseph Crowe: https://josephcrowe.com/blogs/news/autoformer-characteristics
3. Third best is autoformers, but to be better than the fixed resistor network requires some fine tuning, and high quality transformers, I think. Personally I like autoformers, but maybe I like the way they deform the sound. At -2dB or -4dB they are not too bad, but it gets worse the higher you attenuate. Like -12dB, then it you start to hear the problems.
But to attenuate at speaker level is a problem in itself. deep
1. The cleanest sound will always be to match drivers to each other.
2. The second best way is to use a fixed resistor network, at least according to a recent test done by Joseph Crowe: https://josephcrowe.com/blogs/news/autoformer-characteristics
3. Third best is autoformers, but to be better than the fixed resistor network requires some fine tuning, and high quality transformers, I think. Personally I like autoformers, but maybe I like the way they deform the sound. At -2dB or -4dB they are not too bad, but it gets worse the higher you attenuate. Like -12dB, then it you start to hear the problems.
But to attenuate at speaker level is a problem in itself. deep
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