Hey everyone,
You might have observed that I've asked a lot of questions on this forum, and I thank you guys for really helping me understand the basics and then some...So this thread is essentially show that all of your help has not gone to waste. So thank you.
So I've been in the process of building my own amp + speakers since about early February, when I broke my cheapo Logitech 2.1 system. (MSRP $30). I decided I would try to venture into DIY audio. After struggling with some concepts, and money *cough*, I've gotten this far. I'm pretty much done assembling the electronics part. Now I'm off to start the enclosure construction, and speaker construction. Boy, it's a bit harder than it looks.
The amp for the midrange speakers is a 2x LM3886 config and the amp for the subwoofer is an LM4780 in parallel. Yes those Wima MKP4s are real....My wallet is crying. Electrolytic capacitor selection includes. Mostly Panasonic FC and FM. Power supply caps on the LM3886 are Panasonic @ 105C. Power supply caps on the sub board are Nichicon @ 105C. All capacitors are 105C. All film, except for two on the LM4780 are Wima MKP or MKS. Resistors are Xicon metal film and Vishay. All Op-Amps are TI NE5532P.
For the speakers, I'm going with Wolf's Sophomores (HiVi M4N [mid] + HiVi TN25 [tweeter]). For the sub, I'm using Wolf's Triumph/Biumph sub, which uses a 5.25in Tangband subwoofer, and 1x Dayton Audio 8in passive radiator.
I bought the bare boards before I bought the speakers, and I wasn't sure how much power I was going to really need. I really went overkill on the amp. I could have gotten away with a lot smaller, and simpler, but hey, whatever. I can do around 50W/channel (8ohm) on the LM3886 and 120W for the sub (4ohm). The speakers power handling is only about 20W/channel and the sub is only around 40W....So overkill....Yes...Perhaps if I found a bigger load somewhere down the road.
I'm using a subwoofer preamp board which preamps the sub signal, but also has 4 potentiometers used to tune the sub's crossover/phase etc.
Also will be using 2 speaker protection boards which I recapped with Panasonic FC/NHG + a Wima.
It's all being powered by a 2x 25V 250VA toroid.
You might have observed that I've asked a lot of questions on this forum, and I thank you guys for really helping me understand the basics and then some...So this thread is essentially show that all of your help has not gone to waste. So thank you.
So I've been in the process of building my own amp + speakers since about early February, when I broke my cheapo Logitech 2.1 system. (MSRP $30). I decided I would try to venture into DIY audio. After struggling with some concepts, and money *cough*, I've gotten this far. I'm pretty much done assembling the electronics part. Now I'm off to start the enclosure construction, and speaker construction. Boy, it's a bit harder than it looks.
The amp for the midrange speakers is a 2x LM3886 config and the amp for the subwoofer is an LM4780 in parallel. Yes those Wima MKP4s are real....My wallet is crying. Electrolytic capacitor selection includes. Mostly Panasonic FC and FM. Power supply caps on the LM3886 are Panasonic @ 105C. Power supply caps on the sub board are Nichicon @ 105C. All capacitors are 105C. All film, except for two on the LM4780 are Wima MKP or MKS. Resistors are Xicon metal film and Vishay. All Op-Amps are TI NE5532P.
For the speakers, I'm going with Wolf's Sophomores (HiVi M4N [mid] + HiVi TN25 [tweeter]). For the sub, I'm using Wolf's Triumph/Biumph sub, which uses a 5.25in Tangband subwoofer, and 1x Dayton Audio 8in passive radiator.
I bought the bare boards before I bought the speakers, and I wasn't sure how much power I was going to really need. I really went overkill on the amp. I could have gotten away with a lot smaller, and simpler, but hey, whatever. I can do around 50W/channel (8ohm) on the LM3886 and 120W for the sub (4ohm). The speakers power handling is only about 20W/channel and the sub is only around 40W....So overkill....Yes...Perhaps if I found a bigger load somewhere down the road.
I'm using a subwoofer preamp board which preamps the sub signal, but also has 4 potentiometers used to tune the sub's crossover/phase etc.
Also will be using 2 speaker protection boards which I recapped with Panasonic FC/NHG + a Wima.
It's all being powered by a 2x 25V 250VA toroid.
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Nice, keep working on it and report
What will you use for crossover for HiVi M4N [mid] + HiVi TN25 [tweeter]?
Thanks.
I'm using Wolf's Sophomores design so, I'll be throwing together a pair of these:
I'm using Jatzen air coils, Erse films, Erse wirewounds, and Nichicon shunt NPE (22uF).
Thanks! I'm actually looking for some input how some mounting strategies. I know I'd probably be the best one to judge since I have them, but since there are heatpipes, it makes mounting a bit more difficult.
Right now, I think there is enough clearance between the two heatpipes on the smaller heatsinks to drill a hole and screw them in. The sub's amp's heatsink on the other hand uses more heatpipes and it's base is solid copper...So I can't drill into that. I'm hoping that I can just mount it preciseley enough that I won't need any screws at all. Perhaps I will just use an insulating pad to fill any pressure problems.
Since they're not solid aluminum I can't really bolt the heatsinks themselves down to my enclosure anywhere either, so I'm considering making a few metal brackets that go over the top of the heatsinks and then bolt on either side.
Still trying to figure out that much out.
Gotta agree with the great heatsink comment, I'm still pretty new to this, but those things are monstersized from the looks of it
I'm not sure if they're that big really, but I think they will cool better than a traditional extruded aluminum heatsink, so being smaller with this sort of design might be fine. I'm also never going to be pushing this amp too much ever, so that's also a factor.
So didn't really have time to do any real work, but I did get some more stuff in from Mouser, that I had forgotten. (The shipping from me forgetting things on this build is getting out of control.).
I have a cheap camera but with a black box and some nice lighting, you can really make it look nice, so sorry if I went overboard with the pictures!
But first, I have a general layout that I will be using for the amp. I'm using a wooden case, but don't shoot me for it. This thing is already costing me a lot, and it's one of the tradeoffs I'm willing to make....Subwoofer board is to far right. Left and Right channel is the board in the middle. The small rectangular board is the subwoofer preamp/tone control. Not sure if there's a quote on quote "better" layout but, if you have any ideas, I'm looking for them...Here's what I'm thinking about layout.
Got some other parts as well. I got this beautiful Nikkai 25A toggle switch. I would have bought a rocker switch but they are all intended for metal panels, not 1/4 wood, so this will do. I'm pretty sure it will handle mains perfectly fine. It's not small by any means. Body is almost the size of a 9V battery.
For volume control on the left and right channels, I went with 2x Bourns 50K carbon audio tapers. I would have bought dual gange, but I like the idea of having control over both channels for some reason.
Lastly, here's the power supply board I'll be using for powering the two fans I have @ ~8.5VDC. It wasn't meant for this purpose, hence the 50V Nichicons. But all the same, it will do a great job. Even have some MLCC ceramics, and a Wima MKP4 in there for kicks.
As luck would have it, I had my headphones hooked up to my computer's headphone jack the other day, and I tore it out of the jack as I was walking away (6f-oot cord. Sennheiser HD201)
So..I'm taking this opportunity as an excuse to integrate a headphone amp right into the big amp. The thought is to make Tangent's cMoy minus the rail splitter part, since I happen to have a 6-0-6 center tapped transformer in the amp for the sub preamp board and for the two fans. The trafo is rated at 1A, so I don't think it should have a problem powering a few low current things like that.
I'm going to need a means of switching from power amp to headphone amp. I believe I'll achieve this by hooking up the inputs from the RCA jacks to a 4PDT switch which will let me toggle between big amp and headphone amp. I think I'll get a big 25A Nikkai, because I'm thinking it would be best to use a big switch to ensure lots of contact, and to limit any loss in signal. Just a theory though.
Well that's it for now. Not sure why I'm updating anyone. Didn't really do anything....
I have a cheap camera but with a black box and some nice lighting, you can really make it look nice, so sorry if I went overboard with the pictures!
But first, I have a general layout that I will be using for the amp. I'm using a wooden case, but don't shoot me for it. This thing is already costing me a lot, and it's one of the tradeoffs I'm willing to make....Subwoofer board is to far right. Left and Right channel is the board in the middle. The small rectangular board is the subwoofer preamp/tone control. Not sure if there's a quote on quote "better" layout but, if you have any ideas, I'm looking for them...Here's what I'm thinking about layout.
Got some other parts as well. I got this beautiful Nikkai 25A toggle switch. I would have bought a rocker switch but they are all intended for metal panels, not 1/4 wood, so this will do. I'm pretty sure it will handle mains perfectly fine. It's not small by any means. Body is almost the size of a 9V battery.
For volume control on the left and right channels, I went with 2x Bourns 50K carbon audio tapers. I would have bought dual gange, but I like the idea of having control over both channels for some reason.
Lastly, here's the power supply board I'll be using for powering the two fans I have @ ~8.5VDC. It wasn't meant for this purpose, hence the 50V Nichicons. But all the same, it will do a great job. Even have some MLCC ceramics, and a Wima MKP4 in there for kicks.
As luck would have it, I had my headphones hooked up to my computer's headphone jack the other day, and I tore it out of the jack as I was walking away (6f-oot cord. Sennheiser HD201
)So..I'm taking this opportunity as an excuse to integrate a headphone amp right into the big amp. The thought is to make Tangent's cMoy minus the rail splitter part, since I happen to have a 6-0-6 center tapped transformer in the amp for the sub preamp board and for the two fans. The trafo is rated at 1A, so I don't think it should have a problem powering a few low current things like that.
I'm going to need a means of switching from power amp to headphone amp. I believe I'll achieve this by hooking up the inputs from the RCA jacks to a 4PDT switch which will let me toggle between big amp and headphone amp. I think I'll get a big 25A Nikkai, because I'm thinking it would be best to use a big switch to ensure lots of contact, and to limit any loss in signal. Just a theory though.
Well that's it for now. Not sure why I'm updating anyone. Didn't really do anything....
I can't believe I started this project sometime in Febuary...Simply amazing...And I'm STILL not done yet! Yikes. It's a lot of work: much more than I really expected. Making sure you haven't f@cKed up your wiring when you are working with hundreds of dollars of equipment is pretty serious stuff. I'm going to check everything 9,000 more times to make sure I don't turn this into a $500 smoke machine.
Anyway, I took this picture with my phone, but I'm ALMOST there. Needs a few more finishing touches. But very close!
Since last time I installed the 4PDT output selector switch. It was suggested afterward that I should have used a relay or something, but I think this will be fine. There was bound to be long wire runs anyway due to some of my control boards etc. I have two 12VDC computer fans running at ~8V. One intaking cool air from under the subwoofer amp heatsink, and one as exhaust to the left of the trafo. cMoy Headphone amp in the lower left corner on a regulated +/- 6V power supply.
Anyway, I took this picture with my phone, but I'm ALMOST there. Needs a few more finishing touches. But very close!
Since last time I installed the 4PDT output selector switch. It was suggested afterward that I should have used a relay or something, but I think this will be fine. There was bound to be long wire runs anyway due to some of my control boards etc. I have two 12VDC computer fans running at ~8V. One intaking cool air from under the subwoofer amp heatsink, and one as exhaust to the left of the trafo. cMoy Headphone amp in the lower left corner on a regulated +/- 6V power supply.
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