wow, after contemplating for about half an year, i finally pulled the trigger on them.
part of the reason for the hesitation was the $200 shipping i would have to pay via parts-express to korea.
so the total came out to be $530 just for the parts minus the resistors, capacitors which i can provide on my end.
i hope the price is still worth it
part of the reason for the hesitation was the $200 shipping i would have to pay via parts-express to korea.
so the total came out to be $530 just for the parts minus the resistors, capacitors which i can provide on my end.
i hope the price is still worth it
Ouch! Me too.i hope the price is still worth it
The idea is a speaker that doesn't cost too much. Having to ship the parts 1/2 way round the globe doesn't help the price.
But never fear, it's a fun speaker that you will certainly enjoy.
Ob project with Alpha 15a and aucharm 4 inch fr
Hi.I have a pair of nice sounding aucharm 4 inch full range driver.I wanna build an OB speaker with eminence alpha 15a. Which xo frequency do you recommend? Here is response of aucharm fr.They are 4 ohm drivers
Hi.I have a pair of nice sounding aucharm 4 inch full range driver.I wanna build an OB speaker with eminence alpha 15a. Which xo frequency do you recommend? Here is response of aucharm fr.They are 4 ohm drivers
Attachments
Custom crossover issues
There are quite a number of issues to deal with.... too many to make a crossover point recommendation at this time. Your 4" appears to have a 84 db or so sensitivity. The Emi 15 is around 10 db higher and has a large 10 db peak around 2Khz. And that's just the beginning of what one must deal with to end up with something listenable.
Need to know what your effective baffle width will be as that determines the true OB operating efficiency the Emi 15 will deliver.
Also, what is the FS & QTS of the 4"? Any off axis frequency response data available on the 4"? Knowing the Xmax would help too.
There are quite a number of issues to deal with.... too many to make a crossover point recommendation at this time. Your 4" appears to have a 84 db or so sensitivity. The Emi 15 is around 10 db higher and has a large 10 db peak around 2Khz. And that's just the beginning of what one must deal with to end up with something listenable.
Need to know what your effective baffle width will be as that determines the true OB operating efficiency the Emi 15 will deliver.
Also, what is the FS & QTS of the 4"? Any off axis frequency response data available on the 4"? Knowing the Xmax would help too.
Hı
Thank you for your response
Xmas 2mm
Qts 0.481
Here is the link of item . Please check other specs
Aucharm 4 inch Fullrange Speaker Matched Pair | eBay
I only have full range speaker. I will buy eminence and cut plywood after we make plan. My wife does not want very big baffle. This is all I know.And I built an active xo which have around 340hz cutoff frequency but if you recommend an another xo crossover I can build another one.I am new in building ob
Thanks in advance
Thanks for the info
OK.... A bit suspicious of the T/S parameters... but will assume they are correct for now. Just don't know what you have until you actually measure...
With about 55 sq. CM of area and 2 mm X-max you will need to get out of this driver at around 700 hz or so assuming a 2nd order crossover slope. That would be a -6 db point. You can play it lower with a 4th order, (450 hz or so) but blending with a 15" with steep slopes (say 4th order or higher) is a difficult undertaking.
Do you have the 4" drivers and any way to verify the T/S parameters?
OK.... A bit suspicious of the T/S parameters... but will assume they are correct for now. Just don't know what you have until you actually measure...
With about 55 sq. CM of area and 2 mm X-max you will need to get out of this driver at around 700 hz or so assuming a 2nd order crossover slope. That would be a -6 db point. You can play it lower with a 4th order, (450 hz or so) but blending with a 15" with steep slopes (say 4th order or higher) is a difficult undertaking.
Do you have the 4" drivers and any way to verify the T/S parameters?
Sorry I do not have an equipment to measure the exact response of full range speaker but I believe graphics show true response
And you told around 700hz one diyer built at 800hz. I think it will be OK
Project | Homebuilt Hi-Fi - A user submitted image showcase of high quality home built hi-fi components.
My active xo boards are 12db/octave with opa627 opamps . I think I will remove 15nf caps and put 6.8nf instead of them to make around 750hz xo frequency
So can i start building? ☺
And you told around 700hz one diyer built at 800hz. I think it will be OK
Project | Homebuilt Hi-Fi - A user submitted image showcase of high quality home built hi-fi components.
My active xo boards are 12db/octave with opa627 opamps . I think I will remove 15nf caps and put 6.8nf instead of them to make around 750hz xo frequency
So can i start building? ☺
Another set of almost finished Ultras. Got them tacked together temporarily to listen to them before the heat rolled in for the Summer.
First off, they image like nobody's business. Instruments and vocalists just magically appear in between the baffles.
They do serious bass.
They show off system differences easily. Drop in a cleaner source/amp/preamp/etc and you will be rewarded big time.
The speakers have been broken in listening at a low (to moderate) level with a TDA3116 chip amp. The amp is putting out about 15 watts into 8 ohms with the current power supply. For Jazz, folk and pop/rock (at lower volumes) it's a great combo. Try to go loud or put something on that requires a lot of amplifier head room (orchestras, big bands, Squonk, etc.) and you'll want a *lot* more power. But for evening listening the small chip amp is wonderful and there is a real synergy between the amp and the speakers. It'll do serious justice to a jazz combo.
At this point they need to get their final finish coats applied to make them pretty and then they will be properly glued/braced together.
These are very fine sounding speakers. Don't let the ultra low cost part of it make you think otherwise.
First off, they image like nobody's business. Instruments and vocalists just magically appear in between the baffles.
They do serious bass.
They show off system differences easily. Drop in a cleaner source/amp/preamp/etc and you will be rewarded big time.
The speakers have been broken in listening at a low (to moderate) level with a TDA3116 chip amp. The amp is putting out about 15 watts into 8 ohms with the current power supply. For Jazz, folk and pop/rock (at lower volumes) it's a great combo. Try to go loud or put something on that requires a lot of amplifier head room (orchestras, big bands, Squonk, etc.) and you'll want a *lot* more power. But for evening listening the small chip amp is wonderful and there is a real synergy between the amp and the speakers. It'll do serious justice to a jazz combo.
At this point they need to get their final finish coats applied to make them pretty and then they will be properly glued/braced together.
These are very fine sounding speakers. Don't let the ultra low cost part of it make you think otherwise.
Attachments
Base plate
Donovas.... The base plate is shallow relative to the long wave lengths produced by the woofer and is far enough from the Vifa 3.5" not to mater. So the reflection potential is very low. The base plate does improve the structural integrity and offers a surface to mount the crossover components. And it adds a bit of weight at the bottom of the baffle improving stability. But you can build the Ultra with out it if you desire. Please let us know what you decide to do and good luck with the project!
Donovas.... The base plate is shallow relative to the long wave lengths produced by the woofer and is far enough from the Vifa 3.5" not to mater. So the reflection potential is very low. The base plate does improve the structural integrity and offers a surface to mount the crossover components. And it adds a bit of weight at the bottom of the baffle improving stability. But you can build the Ultra with out it if you desire. Please let us know what you decide to do and good luck with the project!
Hi John,
Yes, I've tried the woofer trap but it was on green drivers in baffles that weren't glued down yet. It sounded like the trap improved the midrange but there were so many baffle resonances going on that it wasn't really a good test. When the baffles are together properly I'll do some listening with and without the trap and try to report how the sound changes.
The baffles are currently undergoing glue therapy. Hopefully the bottom pieces will be finished up later today so I can listen to them properly tonight.
There is truck bed liner for the back of them, too, but that will have to wait. I'm too impatient to put the liner on then wait several days or a week for the smell to subside before putting them back in the house.
Must. Have. Ultras.
Barry
Yes, I've tried the woofer trap but it was on green drivers in baffles that weren't glued down yet. It sounded like the trap improved the midrange but there were so many baffle resonances going on that it wasn't really a good test. When the baffles are together properly I'll do some listening with and without the trap and try to report how the sound changes.
The baffles are currently undergoing glue therapy. Hopefully the bottom pieces will be finished up later today so I can listen to them properly tonight.
There is truck bed liner for the back of them, too, but that will have to wait. I'm too impatient to put the liner on then wait several days or a week for the smell to subside before putting them back in the house.
Must. Have. Ultras.
Barry
i build them.
first- best bass ever. show room, friend system, do not compare. can do not go back to BR systems
second- not enough detail(?) compare from fullrange, not detailed. but 1 resistor+ inductor vs 2 resistor + 2 inductor + 1 cap. maybe can't compare?
third- speakers take some volume to 'open' sound. this 'open' sound volume too loud for my community. drivers age(?) then better sound? tc9fd need time to age, this i know. peerless the same?
i use good cap- russian polystyrene. carbon film resistors. i live with this speaker for months, then think if better inductor must. 20mh toroidal very expensive.
i build with 15cm stand from wings- crossover parts screwed back on baffle. very clean look. best looking/sounding speaker ever for me.
thank you diyaudio.
hope my english ok!
first- best bass ever. show room, friend system, do not compare. can do not go back to BR systems
second- not enough detail(?) compare from fullrange, not detailed. but 1 resistor+ inductor vs 2 resistor + 2 inductor + 1 cap. maybe can't compare?
third- speakers take some volume to 'open' sound. this 'open' sound volume too loud for my community. drivers age(?) then better sound? tc9fd need time to age, this i know. peerless the same?
i use good cap- russian polystyrene. carbon film resistors. i live with this speaker for months, then think if better inductor must. 20mh toroidal very expensive.
i build with 15cm stand from wings- crossover parts screwed back on baffle. very clean look. best looking/sounding speaker ever for me.
thank you diyaudio.
hope my english ok!
Hi Donovas.
Not as much detail as fullrange? Yes, that does not surprise me. The Manzanita speakers tend to have a slightly recessed midrange which gives them a laid-back, open sound. Many fullrange speakers I've heard (and a few I've built) will have the opposite - a pronounced midrange. They may be all midrange. We tend to hear "detail" in the upper midrange, which fullrange speakers do well. If you took the same midrange speaker and added full bass to it, it would sound less detailed.
I can come down to what is important to you.
Not as much detail as fullrange? Yes, that does not surprise me. The Manzanita speakers tend to have a slightly recessed midrange which gives them a laid-back, open sound. Many fullrange speakers I've heard (and a few I've built) will have the opposite - a pronounced midrange. They may be all midrange. We tend to hear "detail" in the upper midrange, which fullrange speakers do well. If you took the same midrange speaker and added full bass to it, it would sound less detailed.
I can come down to what is important to you.
Peerles 12" SLS woofer
Hello Mr2racer... in an open baffle application the Peerless will handle about 100 watts program input. It is difficult to get it to bottom out as the spider and surround are very progressive at about 10 mm peak of excursion. You know you are done when the bass dynamics start to fall off. This is a rugged woofer which had a lot to do selecting it. If it is abused too much over a long time the rubber surround will start to crack and fail. We are talking a LOT of hard input over several years. Hope this helps.
Hello Mr2racer... in an open baffle application the Peerless will handle about 100 watts program input. It is difficult to get it to bottom out as the spider and surround are very progressive at about 10 mm peak of excursion. You know you are done when the bass dynamics start to fall off. This is a rugged woofer which had a lot to do selecting it. If it is abused too much over a long time the rubber surround will start to crack and fail. We are talking a LOT of hard input over several years. Hope this helps.