The sound I get from the speaker (CHP-90 driver installed) doesn't like me. Not "balanced". Too bright and no body at low frequencies. I believe is the driver. Cabinet is made from 2cm thick "daw" hard foam I have available (internal width ~7" or 18cm to be exact). The "blind side" of acoustic path staffed - not totally - with some thin sheets of very soft "afrolex foam"(I have seen that in some "vintage" British enclosures). The cabinet doesn't seems to leak (not too close the flame of the lighter). Maybe with another building material the results could be better. I don't know. For this reason I like to try the drivers I mention in my post #238 & #239 . Maybe vintage but VERY NICE SOUNDING (from 1993 or so, but new, as I was buy them as "spares" for another speaker I made)
PS. I haven't install any BSC .I installed the CHP-90 ON the baffle externally. I compare the sound with the sound of the clip you upload
Elias
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Looking at the specs for the MA CHP-90, it seems pretty good. I suspect the lack of a baffle step correction may be the source of the brightness you notice. My speakers with BSC are in the circa 83dB sensitivity range at 100Hz. The CHP-90 is nominally an 89dB sensitive driver and will need about 5-6dB of BSC to the upper mid and top end. Try adding about 0.8mH to 1mH and 6.8ohm to 10ohm resistor in parallel as BSC. See if that doesn’t improve the balance. Also, use something closer to polyfill (pillow stuffing) in the closed end to where the first 180deg turn is. Reduce stuffing if you don’t hear enough bass.
This factory response is quite nice and BSC should keep this shape but reduced to about 84dB sensitivity. Image from datasheet:
TS parameters indicates Vas is a bit larger meaning suspension is softer, hence cabinet volume may need to be bigger to allow deeper bass:
This factory response is quite nice and BSC should keep this shape but reduced to about 84dB sensitivity. Image from datasheet:
TS parameters indicates Vas is a bit larger meaning suspension is softer, hence cabinet volume may need to be bigger to allow deeper bass:
Focal units that you attached are perfectly capable units for a compact 2 way classic loudspeaker, the only unknown remaining would be filter.
But how much bigger xrk ? It is - internally - already 18 cm width (externally the "fridge" is about 224mm roughly. I kept all the other internal dimensions as in your sketch. Of course the sound path is a little longer due to the thickens of the daw board.
Elias
Hi !
I know very well the bigger brother of 5K013L, the 6K412L . EXCELLENT sounding driver crossed at 3.8KHz. But I felt in love (visually first & listening to Youtube clip he uploaded) with the enclosures xrk971 design. There is somewhere a FOCAL design x-over for the vintage "point source" Daline 3.1 loudspeaker (a floor stander) but that box has an internal Helmholtz resonator. Not a "book self" loudspeaker as the "PMC-inspired" is
PS. FOCAL was crossing TN-46 (combines the smoothness of fabric diaphragm with the attack of the metal one) at 4.5KHz 12dB/oct slope
Elias
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Let me find some time to run a simulation with the CHP-90 for you. In rough numbers scale volume of cabinet by ratio of Vas. Or 20/14 x 6.8in wide = 9.7in wide. It’s too wide to look pleasant in my opinion so I would extend the volume by increasing the length of the line or cross section area along the depth and height. But even if it was not wide enough, it should provide bass that sounds decent. The issue of brightness is due to lack of BSC.
Thanks xrk.
For the moment I'm digging into this thread
https://www.diyaudio.com/community/threads/tpa3116d2-amp.237086/page-6
to find the documentation for your mod on TPA3116D2.
I quite recently receive this board and ... so-and-so about background hissing. Tested on Dayton Audio PC83-8 (free air).
Maybe TL074 causing the hissing + I don't like at all those 4 yellow ceramic multi..... 2,2μF (225) capacitors .
Elias
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Search for bootstrap mod on the TPA3116 wiki. I wouldn’t worry about the ceramic caps. I use X7R and NP0 on my TPA3255 in the correct places. I also use them in the bootstrap mod. You want low ESR cap - I think it was X7R ceramic.
TPA3116 can be very good amp. The things to chase are upgrade the quality of the output inductor and use quality film cap on output filter cap. Use clean linear DC PSU will improve sound quality (or lots of good filtering).
That TPA3116 thread is a juggernaut. Huge. Have fun! You might just upgrade to TPA325x amps. They are becoming quite cheap now. Of course, great implementation still costs a bit more but sound is worth it.
TPA3116 can be very good amp. The things to chase are upgrade the quality of the output inductor and use quality film cap on output filter cap. Use clean linear DC PSU will improve sound quality (or lots of good filtering).
That TPA3116 thread is a juggernaut. Huge. Have fun! You might just upgrade to TPA325x amps. They are becoming quite cheap now. Of course, great implementation still costs a bit more but sound is worth it.
xrk
nandappe is using some similar amplifier to drive his loudspeakers.
TPA325x is too powerfull for my house (in apartments building). I have seen a review for your amplifier on Youtube. I can't buy that beauty.
So searching for "bootstrap mod" .
Thanks again xrk
Elias
Coax would work of course but XO would be totally different. Interesting thought - I didn’t realize there was a coax variant.
The ready to run (RTR) amp modules used in Warp-1 are now available from my shop for significantly less than cost of Warp-1. You need to provide the PSU, buffer, and chassis though.
xrk
Where do I have to look ?
Send me please a link.
I'm searching https://www.diyaudio.com/community/threads/warp-1-amp.382915/ but I can't find the RTR modules
Elias
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The Vas = 13,3 liters (I can't determine the volume - 0,47 ft 3 - in British units). Can work in to a box designed for a driver that has Vas = 10,2 liters. It is 30% more, but xrk is the master here
Elias
Well seems the break in process over and now it has become more clear and clean with pin point imaging and soundstage, depth layering whatever one can wish for in a compact enclosure. Pretty happy that I build one and a great thanks to @xrk971 .
My chain is pi2aes to denafrips pontus ii over i2s and from pontus to kinki studio ex-m1+, cables are all radioshack onces.
Jmascreen - Glad the speakers are working out great for you. You are using RST28F-4 tweeter and DC130A-8 woofer with passive crossover, right?
Greetings X,
I would like to build a pair of these. With no way to measure the finished result what would you suggest the best material to dampen the line and its quantity?
Your foam core used a polyfill like material, PMC uses egg crate foam and you also mentioned Mr Clean sponges.
i have available all 3 materials.
Thanks for your contributions to us .
I would like to build a pair of these. With no way to measure the finished result what would you suggest the best material to dampen the line and its quantity?
Your foam core used a polyfill like material, PMC uses egg crate foam and you also mentioned Mr Clean sponges.
i have available all 3 materials.
Thanks for your contributions to us .