*** The DIY Audio Thread ***

[p4radox]

Some awesome work in here.

Here's my modest headphone amp that I built a few weeks ago:

Quite pleased with it for my first attempt at any audio DIY. My next project will hopefully be something from 41Hz.com

 

[oli collett]

Cases work out about £50 in parts each. Buying 6 heatsinks got a nice price break dropping them to about £16 each. The panels for all 3 were about £60, they were cut for me by a local company (saved delivery cost). Still need fronts mind, but don't expect them to be that expensive. A bench drill is essential for construction though

http://export.farnell.com/1211720/semiconductor-accessories-prototyping-antistatic/product.us0?sku=FISCHER-ELEKTRONIK-SK-56-100-SA
http://www.metalfast.co.uk/

For transformers, I bought them here:

http://export.farnell.com/toroidal

Now, the one in the bass amp is fine, but the one in the midrange amp is buzzing, which is very annoying, so i'm hesitant to reccomend that. Any of suitable voltage and current rating should be fine; I must have got unlucky with that one of mine, still not sure what to do with it (it buzzes with nothing connected too).

A DIY amp can easily better a commercial one of even 4 or 5 times the cost when constructed properly. Both mine sound far better than my Rotel RA-01 amp. The midrange amp apparently "cannot be touched by any commercial amp under £1000", as told by the many people who have built it and compared it against many commercial offerings. If you build that P3A amp oli using the PCB it should be great and not too difficult to do. As damian666 mentioned you can tweak it too and I know there are a few for that design

Cool. My next sound upgrade was going to be some high end seperates A/V Processor/Power amp, but i might instead build several monobloc's or stereo amps and get an even better processor! Would be a lot of work though!

 

[Kanifee]

Cool. My next sound upgrade was going to be some high end seperates A/V Processor/Power amp, but i might instead build several monobloc's or stereo amps and get an even better processor! Would be a lot of work though!

Great satisfaction at the end of it though, just think of that one of a kind set-up you could have!

 

[dave-lew99]

Nice work p4radox,

But you may notice an improvement by swapping out that 741 op amp for a TI TL072/1 or an NE555

 

[p4radox]

cheers

The 741 is only the power supply op amp (buffer), would a different one really make a difference to such a basic amp?

 

[AbsenceJam]

One thing I would highly recommend if you're a headphone listerner is a crossfeed filter (Jan Meier), very easy to add to an amp or seperate build and I couldn't ever go back to not using one personally.

 

[dave-lew99]

p4radox, in that case it probably won't make all that much of a difference.

741's are excellent for testing (apparently they are indestructable....several blown up ones later i still remain unconvinced )

But using a better op amp for your main audio path should give you better bandwidth and so on, but it does depend on the rest of the design too, but it's a simple and easy upgrade (cheap too talking £1 or so per chip).

It's less important if you're not using a differential amplifier like balanced line recievers where CMRR is important so really, you probably wouldn't notice the difference.

 

[MikeHunt79]

Awesome thread - DIY allows the impossible to become possible. I'm loving the amps of various shapes and sizes especially. Mine are a little more ghetto but I'll post 'em up anyway.

I've become a bit of a class-T fanboy recently, this was my first:

Simply a pre-made ta2024 module modded with more caps and a few other tweaks, and mounted in a car bulb box. FWIW, 15W @ 4R, 0.1%THD (I think). Most importantly, it sounds awesome.

I was now bit by the bug, so I went for the 41Hz.com Amp6Basic (25W @ 4R, 0.1%THD):

I made the case from bit's of Alu table edging from, B&Q. The case is also the heatsink, and the LED's are to let me know when my battery is about to die (when it's being powered from batteries).

This one is a little crazier, it will go in the car once the crossover is done:

4 channel class-t module (same as the 41Hz.com AMP9) mounted in the chassis of a cheap and nasty car amp. I also used the SMPS from the car amp to turn 12v into 24v (with a little toroid unwinding), which should give me 4 x 75W (in theory)...

Finally, work in progress, 6ft high tapped bass horn, tuned to 30Hz. I have no clue how it will sound but hornreap seems to give pretty good SPL plots (around 103db/W from 30-100hz)... This is my project for this weekend, I'm hoping it won't break the glass in my lounge...

Plant pots make an excellent weight when gluing ply.

Adam W: What class-t amp is that? 41Hz.com kit?

 

[Kanifee]

Oioi mike finnally got my amp kit, wounderd how long it would be before i found your Amp6 in here

 

[WillSpengler]

Some nice looking setups here!

Im working on my own DIY tube power amp during the summer months, should be fun

Some pricey interconnects tho!

 

[MikeHunt79]

Oioi mike finnally got my amp kit, wounderd how long it would be before i found your Amp6 in here

I've been really busy making sawdust the past day or so... The Amp6 is probably my fav amp at the moment. Did you go for an amp6basic also, and have you started it yet?

 

[MikeHunt79]

Bass horn is 90% finished! It's ****ing huge, it's taller than me!

All I need to do is mount the driver, drill some holes for Speakon connectors, wire it up and it's done!

 

[B&W]

bloody hell what kind of monstrosity is that, how tall is it and what speakers/how many will you include?

 

[MikeHunt79]

bloody hell what kind of monstrosity is that

It's tapped horn tuned to 30Hz, and has almost flat freq response up to 100Hz. Basically it's a high output sub. It's similar to the Danley DTS-20 (google it) and should put out more bass than 4 x 15" sealed subs...

how tall is it

6ft 2inches

and what speakers/how many will you include?

One 12" Eminence Definimax 4012HO, a great driver as it was a 4 inch voicecoil and intended for PA use.

I'm off to the pub now, but tomorrow I should have it working and hopefully still a house (if it hasn't fallen down due to vibrations).

 

[Kanifee]

I've been really busy making sawdust the past day or so... The Amp6 is probably my fav amp at the moment. Did you go for an amp6basic also, and have you started it yet?

No ended up going for a LM3886 Chip amp kit im going to see how this goes, if all is well im going to get a Amp10 and wack it in the case as the case will be the most expensive thing about it, then next year i want to make the full tripath amp that 41Hz do but ill have to get saving fro that!

 

[james.miller]

It's tapped horn tuned to 30Hz, and has almost flat freq response up to 100Hz. Basically it's a high output sub. It's similar to the Danley DTS-20 (google it) and should put out more bass than 4 x 15" sealed subs...

6ft 2inches

One 12" Eminence Definimax 4012HO, a great driver as it was a 4 inch voicecoil and intended for PA use.

I'm off to the pub now, but tomorrow I should have it working and hopefully still a house (if it hasn't fallen down due to vibrations).

your gonna have a lot of fun trying to get that to integrate

ive been reading up about them myself recently (and saw you over at diy audio) kudos on actually building one

 

[MikeHunt79]

if all is well im going to get a Amp10 and wack it in the case as the case will be the most expensive thing about it, then next year i want to make the full tripath amp that 41Hz do but ill have to get saving fro that!

The LM3886 should be a good starter... If you ever need more power then the 41Hz.com kits are great bang for buck. I hate soldering SMD's tho, I really wish they would make a thru-hole component version of the AMP8.

your gonna have a lot of fun trying to get that to integrate

Shouldn't be too much of a problem, I'm using a DCX2496 as a crossover but the only problem is I end up spending more time tweaking rather than listening to music or films.

ive been reading up about them myself recently (and saw you over at diy audio) kudos on actually building one

The last pic I posted the enclosure was just screwed together. Today I had the pleasure of dismantling it, and reassembling it with bracing and PU glue.

I didn't think this would take that long, but these things are never easy with a hangover... After covering my hands in glue and many cups of tea later I finally got to this stage:

Final panel glued on, the point of no return!

After checking for air leaks with a torch and some test tones, I put a film on...

The first thing that came to mind was "Holy crap that's loud!". It's louder than what I had before, 2 x 12" reflex cabs getting 400W each (4ohms).

This thing is 8ohms is getting 200w yet I still had to turn it down 6db for it to be roughly the same level as the 2 x 12"'s were! It sounds a lot cleaner than my old subs, and also goes stupidly loud. I'm more than happy with it - It's not pretty, but it more than does the job. It also makes the doors and cupboards rattle but you don't hear the rattles if you are not too near to the doors or cupboards. Now I just need to glue down all the china and reinforce the glass.

The only downside it's that it's a bit on the heavy side... The enclosure is 30Kg as I made it from 18mm Ply. Also the driver is 12Kg, so the only way I can move this myself is with one of those trolley things!

 

[james.miller]

what a monster i really want to build a taped horn, but thats pushing it when i live in a flat now. frankly i only have these concrete floors to thank for the fact that the neibours havent complained about my sealed 15" yet....


...although saying that the guys upstairs are playing dance music and shouting right now they dont want to start an SPL contest with me, not at 1 in the morning the GF has to get up in 4 hours and im amazed it hasnt woken her yet.


.....that tapped horn might be getting built yet.....

 

[MikeHunt79]

Remember, overkill is never a bad thing... There will be a time when your neighbors go on holiday, and you'll be able go nuts with the volume control then. All the info you need to build one if in the diyaudio thread. I was pretty lucky with my driver tho, as it happens to work really well in William Cowan's 30Hz enclosure, so I went for the easy option and made the 30Hz enclosure.

I only got thing thing powered up at 11pm so didn't really have much time to tinker with it, I intend to run the amp bridged which will give 800W (it's a PA amp), so once I get they limiter and delays set up, it should sound even better with any luck.

 

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what a monster i really want to build a taped horn, but thats pushing it when i live in a flat now. frankly i only have these concrete floors to thank for the fact that the neibours havent complained about my sealed 15" yet....


...although saying that the guys upstairs are playing dance music and shouting right now they dont want to start an SPL contest with me, not at 1 in the morning the GF has to get up in 4 hours and im amazed it hasnt woken her yet.


.....that tapped horn might be getting built yet.....

I say........................... BUILD IT

Fantastic build there, a true piece of DIY art. Forget artists and their frozen dogs, or man in bear suit walking around an office, build some DIY audio and submit it as art.

Im scared to go back to subs after the booom booom of the poor logitech z5500 sub, but it did the job for movies, and is now hooked up to the rents sky box an brothers 360, so does a stellar job there.