I've been a lurker on here for a while. I'm fairly active on Home Theater Lounge (formally HTT) and some what over on AVS.
I feel the advice I need will best be found on this site.
Over the 4th my brother and I built a set of BK-12 kits for the Fostex FE126En. I'm about to buy the drivers. I'll do the tips I read to do to the basket; duct seal putty and felt on the magnet. Cheap tweaks that can't hurt.
Here is a pic from my phone. Once I get the drivers, I'll use a better camera. (that's an Adire 81 in the background. My HT system is all Adire.)
We used black and red paint, stressed it and then sealed it. It was cool to do this with my brother. He's the master carpenter of the family.
This is my first experience into full range drivers. These aren't for jamming and rocking the house. I have a system for that. That said, I feel I may need a sub to fill out the bottom end. I've heard it can be a challenge to integrate horns with a sub. I'm going to try a tapped horn with a 8" or 10" like what Lilmike's Cinema T-6 designed over on AVS. I have a Dayton 10" Classic or the MCM 55-2421 to choose from.
Eventually I'll build a tube amp kit. For now these will be driven with SS amps. I have an Adcom GFA-555 and GTP-500 that's collecting dust that I hope will do the trick for now. While it's WAY too much power, I'm not going to crank them. I may buy a small SS amp from PE if the Adcom is too crazy to control.
Anyway, on to the point of this thread. What are the challenges of matching a sub to these drivers? The sub "should" be around 92db efficient. I don't recall what the Fostex are in the BK-12. Anyway, I guess it's all about playing and seeing how it works huh?!!! Any suggestions? Is it worth trying to add a sub? I listen to all kinds of music; jazz, classical, rock, country, classical. But this will be my jazz/classical system.
I love this hobby. There are many upgrades to come, it'll be like a whole new system each time.
My next biggest decision is what tube amp kit and what upgrades. That's for another thread later.
All thoughts and opinions are appreciated!
I feel the advice I need will best be found on this site.
Over the 4th my brother and I built a set of BK-12 kits for the Fostex FE126En. I'm about to buy the drivers. I'll do the tips I read to do to the basket; duct seal putty and felt on the magnet. Cheap tweaks that can't hurt.
Here is a pic from my phone. Once I get the drivers, I'll use a better camera. (that's an Adire 81 in the background. My HT system is all Adire.)
We used black and red paint, stressed it and then sealed it. It was cool to do this with my brother. He's the master carpenter of the family.
This is my first experience into full range drivers. These aren't for jamming and rocking the house. I have a system for that. That said, I feel I may need a sub to fill out the bottom end. I've heard it can be a challenge to integrate horns with a sub. I'm going to try a tapped horn with a 8" or 10" like what Lilmike's Cinema T-6 designed over on AVS. I have a Dayton 10" Classic or the MCM 55-2421 to choose from.
Eventually I'll build a tube amp kit. For now these will be driven with SS amps. I have an Adcom GFA-555 and GTP-500 that's collecting dust that I hope will do the trick for now. While it's WAY too much power, I'm not going to crank them. I may buy a small SS amp from PE if the Adcom is too crazy to control.
Anyway, on to the point of this thread. What are the challenges of matching a sub to these drivers? The sub "should" be around 92db efficient. I don't recall what the Fostex are in the BK-12. Anyway, I guess it's all about playing and seeing how it works huh?!!! Any suggestions? Is it worth trying to add a sub? I listen to all kinds of music; jazz, classical, rock, country, classical. But this will be my jazz/classical system.
I love this hobby. There are many upgrades to come, it'll be like a whole new system each time.
My next biggest decision is what tube amp kit and what upgrades. That's for another thread later.
All thoughts and opinions are appreciated!
Michael - a few random thoughts
The BK12 or any BLH does not increase the overall efficiency of the driver, and assuming that the woofer(s) will be separately powered, you probably needn't worry too much on matching the sensitivity of the woofer to the main system.
The Dayton seems like a great bang for the buck driver, you're probably already aware of its positive reviews. The questions would be which enclosure type would most closely match the dynamics of the FE126/BK12, and are you constrained by physical size.
FWIW, I'm of the opinion that a pair of smaller woofers offer a lot of advantages over a larger one, even when XO'd low enough to run in mono. A quick way to test that might be to borrow something for the Fostex and run the Adires as subs with a quick 'n nasty passive line level XO and the Adcom pair. Of course, you might already have enough spare amps lying around ( if not, you likely soon will)
edit:
I just reread your opening sentences, and realized that you probably already have all the signal processing and amplifier channels you need for such testing in the form of a surround receiver.
Set up the speakers with mains (BK12) as small, no center or surrounds, and experiment with the XO frequencies to LFE channel starting around 80Hz. Note that the higher you raise the XO, the more dynamics and SPL you can achieve with the Fostex before distortion.
I've built a few dozen or so subs, and am a huge fan of outboard amps for these whenever space is not at a premium - the Dayton APA150 is a great candidate for this application. I includes an adjustable LP XO, but for maximum system improvement, it's still a good idea to HP the Fostex drivers.
The BK12 or any BLH does not increase the overall efficiency of the driver, and assuming that the woofer(s) will be separately powered, you probably needn't worry too much on matching the sensitivity of the woofer to the main system.
The Dayton seems like a great bang for the buck driver, you're probably already aware of its positive reviews. The questions would be which enclosure type would most closely match the dynamics of the FE126/BK12, and are you constrained by physical size.
FWIW, I'm of the opinion that a pair of smaller woofers offer a lot of advantages over a larger one, even when XO'd low enough to run in mono. A quick way to test that might be to borrow something for the Fostex and run the Adires as subs with a quick 'n nasty passive line level XO and the Adcom pair. Of course, you might already have enough spare amps lying around ( if not, you likely soon will
) edit:
I just reread your opening sentences, and realized that you probably already have all the signal processing and amplifier channels you need for such testing in the form of a surround receiver.
Set up the speakers with mains (BK12) as small, no center or surrounds, and experiment with the XO frequencies to LFE channel starting around 80Hz. Note that the higher you raise the XO, the more dynamics and SPL you can achieve with the Fostex before distortion.
I've built a few dozen or so subs, and am a huge fan of outboard amps for these whenever space is not at a premium - the Dayton APA150 is a great candidate for this application. I includes an adjustable LP XO, but for maximum system improvement, it's still a good idea to HP the Fostex drivers.
To use your horns for what they were build to do, I'd say pass at 80 - 100 Hz, depending on the filter type, seeing as the Fs is 83.
If you are not going to play loud, like say 85 dB, you'll get very little cone movement in a horn.
Beautiful cab BTW.
Looking at the hole cut-out I think I see two crucial things missing though (esp. for a featherweight paper driver). 1: Chamfering on the inside of the driver hole (not where the screws bite though). 2: Padding on the side walls (ideally something thicker and more sound absorbent than polyfluff).
Both things can still be easily done through the hole with a little care though. Use a rasp to chamfer and clue some felt to the inside with a few spots of contact glue.
If you are not going to play loud, like say 85 dB, you'll get very little cone movement in a horn.
Beautiful cab BTW.
Looking at the hole cut-out I think I see two crucial things missing though (esp. for a featherweight paper driver). 1: Chamfering on the inside of the driver hole (not where the screws bite though). 2: Padding on the side walls (ideally something thicker and more sound absorbent than polyfluff).
Both things can still be easily done through the hole with a little care though. Use a rasp to chamfer and clue some felt to the inside with a few spots of contact glue.
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Thanks for the response guys.
I will be playing a bit with tweaks.
Squeak, I will be adding some padding on the inside. At least to the areas I can reach my big old hands into. In my research for this cab, I didn't see anyone else use it, but want to try anyway. And I'll chamfer the holes once I see how the drivers fit. Good tip! I want to make the drivers easily removable so I can play with the polyfluff to fit my taste.
I've heard some good things about this amp, so it's one I'm willing to try. If it sucks, it will find it's way to the garage system.
Amazon.com: FiiO A1 Mini 2x14W Class-D Digital Audio Amplifier: Electronics
I'll definitely be playing with the XO when I add a sub!
Gotta scoot. Break is over!
I will be playing a bit with tweaks.
Squeak, I will be adding some padding on the inside. At least to the areas I can reach my big old hands into. In my research for this cab, I didn't see anyone else use it, but want to try anyway. And I'll chamfer the holes once I see how the drivers fit. Good tip! I want to make the drivers easily removable so I can play with the polyfluff to fit my taste.
I've heard some good things about this amp, so it's one I'm willing to try. If it sucks, it will find it's way to the garage system.
Amazon.com: FiiO A1 Mini 2x14W Class-D Digital Audio Amplifier: Electronics
I'll definitely be playing with the XO when I add a sub!
Gotta scoot. Break is over!
I did see those too. Guessing, they are both a good line. I wouldn't mind A/Bing them! For the price, if I don't like the Fiio, the Topping would be next. I didn't NOT pick the Topping for any reason. Just picked the Fiio.
I read a few good reviews on the Fiio and decided to pull the trigger last night. <shrug> We'll see!
We've all pulled the trigger on spec / rumor at least once . I recently did myself for some gear for a small restaurant system - Dayton house brand 12 channel amp ($449) and NuForce Icon iDo DAC/pre amp ( $140). For a simple iPod based background system it's drop dead simple and works like a charm.
. I recently did myself for some gear for a small restaurant system - Dayton house brand 12 channel amp ($449) and NuForce Icon iDo DAC/pre amp ( $140). For a simple iPod based background system it's drop dead simple and works like a charm.
While I don't have a T amp handy, I'll certainly report back on the FiiO.
As I mentioned in my first post, I have a few things to play with. I forgot to add I have a Lepai DMA215. I can't find info on it other than what is on the box and it states 2X15. LOL This thing is huge! I got it free from PE when I bought some Dayton B652 bookshelf speakers. The SD card doesn't work. For free, it was worth every cent!
As I mentioned in my first post, I have a few things to play with. I forgot to add I have a Lepai DMA215. I can't find info on it other than what is on the box and it states 2X15. LOL This thing is huge! I got it free from PE when I bought some Dayton B652 bookshelf speakers. The SD card doesn't work. For free, it was worth every cent!
Although only available as either a prebuilt eval board or as bare IC for a diy amp, I can say that the Texas Instruments TPA3116D2 sounds excellent. Better than Tripath, better than my Yamaha RX360 class AB, and better than LM3886 Gainclone type. If someone starts making these packaged like a Topping or Fiio it will be very competitive. 50 watts/ch and very low distortion and great detail.
http://www.diyaudio.com/forums/class-d/219730-tpa3118d2-15.html#post3433693
http://www.diyaudio.com/forums/class-d/219730-tpa3118d2-15.html#post3433693
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Thanks for posting! More things to research! Oh, and spend money on. Looks like more OT will be needed.
Lepai is absolutely the bottom of the barrel as far a quality. Since your model is not in the PE catalog, I presume that they were clearing the shelf. I don't know which chip is in it, but it is probably a T2020 or T2022. If you have a power supply large enough to support it, that amp will give you ~7w/ch @ 0.1% THD into 8 ohms. The Topping's are much better built, but are still using the now ancient TriPath chips. The FiiO, as Dave pointed out is using a NXP chip a generation newer. I have now idea about build quality, but IMO you need to spend upward of $200 to get a decent quality D-amp with any guts to it.
Bob
Bob
LOL Yeah I know the Lepai is at the bottom. I only listened to it on the Dayton B652s for about 5 min or so. Not terrible, not great, but certainly good enough to make noise out in the garage. Oh, and it has a remote!
Before I make the investment into a much higher end amp I want to do more research and see what you guys have to say on here. It's been a long time since I've been up to date on stuff. A DIY amp seems like it could be a fun adventure and some great bang for the buck. So somewhere down the road I expect that to happen. Maybe a tube amp because they look so cool glowing. Who knows!
I've built several computers, but SS and tubes are a whole new ballgame.
Just checked the kits plan on Madisound out of curiosity and it seems it is already chamfered? A little more can't hurt, if done with care, but it seems you don't have to.
I don't get how side padding isn't in the plan though, especially since the drawings were made by Dave.
Remember that the 126 is 93 dB, you'll easily get by with 15 watts into 8 Ohms.
Now, a stronger amp might be able to sound more authoritative at lower levels, but you (or someone else) also run the risk of accidentally blowing the drivers.
I don't get how side padding isn't in the plan though, especially since the drawings were made by Dave.
Remember that the 126 is 93 dB, you'll easily get by with 15 watts into 8 Ohms.
Now, a stronger amp might be able to sound more authoritative at lower levels, but you (or someone else) also run the risk of accidentally blowing the drivers.
We built the cab, it isn't a flat pack. My brother freaked me out; he looked at the cut list and just started cutting. I guess with 25 yrs of experience he should be able to do that. Me, I'd have to draw every single piece out and measure 10 times.
The 56.3 degree angle? No problem when you have one of these. The kid has some serious woodworking tools.
I plan on playing with the padding and stuffing till it's to the point I really like it. I do realize I don't need anything more than 15 watts. I have a much bigger system if I feel the need for concert levels. I'm curious to hear what kind of punch it has, but no matter what I plan on adding a sub to lower any risk of over-excursion . (hence the title of the thread)
FYI, since BK-12m was designed as a kit speaker for Madisound, I assumed it would be easier for them to supply hollow-fibre stuffing in the requisite quantities than lining material. So that's what I specified. Since it is a scoop-bin style back-horn, stuffing is also typically a little more, not less, effective since it can be evenly distributed through the cross-section of the horn rather than being fixed to the boundaries.
The plans do recommend fill and make no mention of lining. IMO, try it and see. How do we know if it was tried or not? It's just time right? I read someone put some felt on the panel behind the driver and liked that tweak. I've never had a horn speaker and so I've never played with tweaking one. I'm looking forward to playing. The FiiO is out for delivery! Drivers tomorrow!
Indeed they do. I know this, because I designed it. Anything else is for the end user to experiment with. This is DIY after all, and not being a magician, I can't account for all tastes / rooms / systems. Playing with damping is usually worth doing to help dial speakers in to a given set of circumstances -particularly with horns. FWIW, I strongly advise avoiding open-cell / egg-crate foam. Its damping properties are abysmal.
Anything else is for the end user to experiment with. This is DIY after all, and not being a magician, I can't account for all tastes / rooms / systems. Playing with damping is usually worth doing to help dial speakers in to a given set of circumstances -particularly with horns. FWIW, I strongly advise avoiding open-cell / egg-crate foam. Its damping properties are abysmal.
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Well it's awesome to meet you Scott!Indeed they do. I know this, because I designed it.
I wasn't thinking of the egg create at all. Polyfil ok??? With it being assembled, I obviously can't put anything in the top where you listed it as optional. Did you notice a lot of difference with stuffing there? Anything else you did to them that you liked, or more importantly that you didn't like?
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