Depending on how tight of a fit you have between the driver and cutout, it doesn't hurt to put a thin ring gasket of plumbers' putty. A tight seal may be essential for the best bass extension. Don't want a pinhole leak to ruin your bass. A foam rubber gasket can also be cut but the lip seems very narrow.
It's Bob's interpretation of X's interpolation of a picture
Anyway, still waiting, so I did some physical readings of the actual build. It will be interesting to make a linear graph of the dimensions. Don't think this first one will be pretty.
Looks good Bob. Go with it and let's get first sound now that your drivers are there!
Better to start with minimal stuffing and increase if needed. In my experience, it's best to start off with no stuffing, but instead lining the chamber walls with lightweight absorbent material, such as pieces of a towel to kill internal reflections.
Start with light stuffing, say half density of what a pillow uses. Can always add more via cutout. The question is should a little be added in any of the channels? I would also add a light amount in the thin channel right after the throat - make sure it is teased out of one single wad of stuffing. This way, you can always remove with a wire hook through the throat hole. But you can never put it back. This location may be needed because it is the few places with two parallel walls that can support a standing resonance and it may help to absorb back end reflections in a quarter wave pipe.
Yes, as X has mentioned, make sure it is thin. If it's heavy you can decouple the basket from the baffle and lose the potential value. With a wood ring in behind I would not bother, you'll get a god seal. A pinhole is less lossy than a 'floating' basket might be.
AND THE VERDICT IS......
"Well worth the effort !
Sorry I couldn't say super fantastic, but I'll be honest. It has a very clean firm low end. I did have one leak at the cable entry and the internal pressure showed it immediately. The air path is working fine.
At three feet from the speaker there is enough SPL to flutter/vibrate the legs on my pants. Vibrations carry across the room clearly though not with the heft of a large speaker and a properly designed wood cabinet.
It is difficult to really judge as too much high end is reaching the driver itself. I think it will sound completely different with a crossover. Haven't had time to check how much top end is coming from the mouth but I can say it's not a lot
Here is the big payoff -I plugged in a Cornu without touching anything but the pause button and wow! This thing has equivalent bottom - maybe a bit more - but the cornu sounds like a mush ball in comparison to the DNA horn.
I have no hesitation about completing it's twin and anticipate hearing the full stereo effect will be something special. I may have to eat my words later, but this driver is outperforming the Vifa from the mids down.
Can't wait to hear reports on the wood version. I'll remind us all that half the value of FC is prototyping and sometimes we get something that in itself is useful and complete. I bet this thing will be gorgeous in wood and a little help on the top end. As is, many builders will be satisfied with the performance as a final solution
I tested with a Walkman -> BrianGT -> DNA. I have a copy of TreuRTA and will calibrate and post what I find.
I'm happy - well worth the effort and highly promising.
"Well worth the effort !
Sorry I couldn't say super fantastic, but I'll be honest. It has a very clean firm low end. I did have one leak at the cable entry and the internal pressure showed it immediately. The air path is working fine.
At three feet from the speaker there is enough SPL to flutter/vibrate the legs on my pants. Vibrations carry across the room clearly though not with the heft of a large speaker and a properly designed wood cabinet.
It is difficult to really judge as too much high end is reaching the driver itself. I think it will sound completely different with a crossover. Haven't had time to check how much top end is coming from the mouth but I can say it's not a lot
Here is the big payoff -I plugged in a Cornu without touching anything but the pause button and wow! This thing has equivalent bottom - maybe a bit more - but the cornu sounds like a mush ball in comparison to the DNA horn.
I have no hesitation about completing it's twin and anticipate hearing the full stereo effect will be something special. I may have to eat my words later, but this driver is outperforming the Vifa from the mids down.
Can't wait to hear reports on the wood version. I'll remind us all that half the value of FC is prototyping and sometimes we get something that in itself is useful and complete. I bet this thing will be gorgeous in wood and a little help on the top end. As is, many builders will be satisfied with the performance as a final solution
I tested with a Walkman -> BrianGT -> DNA. I have a copy of TreuRTA and will calibrate and post what I find.
I'm happy - well worth the effort and highly promising.
