aucharm 4" B.I.B

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Hi everybody,
new to the forum I just wanted to get these of my chest. Got interested in speakers a couple of months ago (as a musician and music-lover I´ve always been interested in Hi Fi and sound-systems, but I´m new at the DIY-thing). Found a pair of those Aucharm 4" full-range at eBay. Then out of discarded IKEA bookshelves I built a pair of folded horns, the Terry Cain design "Bigger is Better" (I think that is what they are called). Total cost $100. They sound really nice - money well spent. And...they do have bass, but maybe not that loud or that tight and well focused. But then again, not bad at all. Anyway, you know how it is, you get bitten by the bug and you can´t stop. Now I just aquired a pair of Aucharm´s Diatone p610 clones and with them ( and a few items more) I´m building an open baffle project of sorts (with a few twists). But as I am in the middle of the building process, and I really don´t want to hear that I´m ignorant and naive (I know I am - after all I´m new to this) or that I can´t or shouldn´t do like that, I´ll post that build when it´s ready.


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Thanx for the interest shown. I´m sad to say that the work was badly documented. I´ve got this one picture. As far as the shelves - I don´t know if IKEA furniture goes by the same names globally, but the sides of the speakers are the sides of the Billy bookshelf (same measures) and the front and back are the sides of the Benno CD-shelf. So that makes the speakers 21cm wide, 28cm deep and 205cm(!) tall. Yeah, they´re tall. As far as damping is concerned, they´re lined internally with felt and the upper part of the horn i.e. above the driver, is stuffed with wool. Now.. I have been thinking of just throwing some more wool in them to see what happens, but I´m not really displeased with the sound and I´m buzy with my new project, so...maybe later.


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Do you use any screws to hold the boards together or just glue? Did you run the BIB calculator to get the dimensions or did you make it based on available wood length? That is a very long BIB for a 4 in driver - you may achieve better performance if optimized the cabinet dimensions. Nice looking BIB though. I had to put stuffing at the bottom bend or else it was too boomy in bass.
Well, actually I did use skrews (and glue). I figured that since the boards were used anyway, the detailfinish wouldn´t be that fantasitic anyway. And I didn´t have enough wooden clamps(?) for the glueing. I did run the calculator, and yes it is about 20-30 cm too tall, but I figured what the h-k. Supposedly the BIB is a forgiving design anyway. And the bass isn´t that boomy - just not audiophile enough
which cabinet to build?

Hi.I listened these aucharm speakers and liked them.I am planning to build one of these cabinets but could not decide yet.CNC cutter told me to bring CAD files to cut the mdf.Which one can sound better?TQWT or back loaded horn?Thanks


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Hi. Funny that someone found this thread, as I have recently been thinking of making a new entry. I did some remodeling at home and these speakers ended up in my study. I haven´t really listened to them for a year, but now they are my computerspeakers and they sound way better than I remembered. Especially the bass is impressing. The only difference now is that the room is smaller and that I listen to stuff from the net, so it´s basically compressed. Maybe that makes a difference, I don´t know. Anyway I´m really impressed by both the drivers ( talk about bang for the buck) and the speakerdesign (B.I.B.) As far as your question is concerned, I´m not really the guy to ask, but I would go for the TQWT as it is the most similar to my speakers. (just upside down, basically) If I was to make any more speakers with these drivers I would be interested in trying the Frugalhorns, or maybe some double-mouthed horns. All the best...
I´m sure the blue indicates damping, like lambs wool or polyurethan foam.( for my last project I went to IKEA and bought the cheapest pillows they had and took the polyester wool inside to use as damping in transmissionline.) I would also line the inside with something damping, like felt. ( I was in Istanbul a couple of months ago, btw.)
I did run the calculator, and yes it is about 20-30 cm too tall, but I figured what the h-k. Supposedly the BIB is a forgiving design anyway.

Correct, if you were to read through that incredibly long thread or at least search 'GM' to see my responses you would find that it's far better to get the pipe either near enough to get ceiling loading or inverted with good floor coupling than tuning the cab per the calculator.

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