Jaycar Headphone Amp Kit

[PinkFloyd]

Got this kit from Jaycar in Australia a couple of weeks ago and thought I'd take a photo of the packaging when I was out in the workshop earlier.... erm, I went a stage further and populated the board whilst I was out there ;D

The amp kit was £8.50 and incredible value for money in my opinion, there is also a seperate PSU kit which is around £5.50 I will upload pics of it here as soon as I've put it together.... oh, and the toroidal transformer will set you back about £8.00.

I decided to put it together with the stock parts just to see what kind of headphone amp £8.50 can buy you from the land of the kangaroos... Stock parts are surprisingly good quality for the money, hell, the dip8 socket is a turned pin gold plated type, the opamp a Burr Brown OPA2134, the electrolytics are "suntan" varieties, metal film resistors, BD139 / 140 transistors and all for £8.50, very good indeed.

Took me about one and a half hours to populate the amp board, there's everything you need including a reel of solder. The only thing that is not supplied is a potentiometer (volume control) and an enclosure etc.

I hope to get the PSU board completed as soon as I get my backlog of pinkies out of the way and will return to this thread once I get the Jaycar up and running.... try her stock for starters, and maybe get a bit more adventurous further into the thread

In the meantime...... here are some pics of what £8.50 buys you in OZ:


Included is a comprehensive construction manual, PCB, parts and solder.


Bottom side of the PCB


Parts


Parts


Parts


And more parts!


Completed PCB (winding the inductors was fun )









Easy to follow instructions, the 1 watt resistors are too big for the pitch on the board but can be tombstoned into position, the 100nF caps positioned slap bang next to the BD139 /140 are a PITA, it was only after I'd fitted the BD139/140 close to the PCB I found the 100nF caps would foul the heatsink fixing bolt..... no biggie, I'll just mount the 100nF under the board. All in all a VERY simple kit to put together, will be fun getting the whole shebang into a decent enclosure.

Cheers for making me aware of this guy Sandy

[leo]

Thats amazing value for money! looking good Mike

[Deleted]

Mike
Don't expect great results as standard. The LKM4562 and other mods make a huge difference.
I am now using it in preference to the Voyager using Sony headphones. Supplying via a JLH PSU add on gives even further gains.
Alex

[Deleted]

Miguel
I suggest that you wait until Mike has not only listened to it in standard form , but also done some further mods. Actually, you are probably better off getting the case, perhaps an Alps potentiometer, which Jaycar doesn't sell, as well as a 15-0-15VAC 30VA toroidal transformer designed for USA mains supply. U.K. and Australia are 230-240V systems.
Alex

[PinkFloyd]

Must get some better quality pictures, my rechargeable batteries keep running flat and the camera does not like flat batteries, takes some right old blurry photos.

Alex, I have the LM4562 and will try it along with a few more once I get this puppy up and running, still waiting for the toroidal to arrive.... have a stash of RK27 (blue Velvet) 50K log pots and will probably source the enclosure from Audiokit.it..... I doubt the amp will stay stock for long but you are pretty limited in what you can fit as the pich / pads are pretty small in places and not much room to fit mama honkers..... NICE looking amp for the money though, may just do an all in one enclosure and I have a couple of Clairtronic 15 - 0 - 15V encapsulated trannies should I decide to go that route instead of the toroidal..... maybe a nice mu-metal enclosure for the encapsulated too

It will be a few days before I do more but will keep the thread alive....... you going to try one Leo?

[leo]

admin said:

It will be a few days before I do more but will keep the thread alive....... you going to try one Leo?

Maybe, The Kumisa and dac isn't cased up yet
I've no problems with the electronics side, its the metal work I'm damn slow at

[leo]

Also got the classA amp to case up

[Deleted]

Miguel

www.welbornelabs.com/modsandmodules.htm

They seem to have some very nice looking modules.
Alex

[PinkFloyd]

leo said:

I've no problems with the electronics side, its the metal work I'm damn slow at

Join the club! You only have one go at the drilling too..... get it wrong and the whole enclosure is toast. The audiokit Galaxy range are very nice but very thick front panels, looking forward to this build though.... it's been quite some time since I put one together.

[rossman]

I might try and pick one of these up if I get over to Aus.

Mike would this be suitable for a total novice? and any recommendations for a good inexpensive iron that would make the job easier, the one I have now takes forever to heat up after doing a joint?

[PinkFloyd]

I remember the days where I would get an amp kit in the morning and post the completed amp (casework the lot!) on Head-Fi in the evening...... jesus christ I must have had a lot of spare time on my hands back then!

I've only today got round to populating the PCB and it was an absolute breeze taking me 25 minutes (and that was going slow) a nine year old could do it, so there you go Rossman get your credit card out and order one from jaycar

As this comes together, the amp board.... the PSU board and the transformer it's becomming evident that this is one HELL of a bargain.... £13 for the PSU and amp boards AND all the parts??? absolutely MENTAL! If these were being sold by the likes of Williams Hart over here in the UK he'd be charging more like £150 (seriously!) simple to put together kits, with comprehensive instructions and all the parts (even solder for christ's sake!) phenomenal value and a big thanks to Alex (SandyK) for pointing us in the direction of Jaycar. I don't need to power this up to know it's gonna sound the dog's bollocks, you can smell the quality a mile off.

I have deliberately gone "stock" with all the components and will fire the amp up 100% stock.... you have to have a reference point to begin with, no point running before you can walk and populating the boards with boutique parts unless you have to and you'll only learn about the ins and outs / strengths and weaknesses from stock and can tweak at leisure once the stock circuit is up and running.

Just a case of sourcing an enclosure now, I may well go down the el cheapo corned beef tin type of job and spray it a nice understated grey... similar to the 80's hairshirt chiarra enclosures:



Who gives a damn what it "looks" like? It will be a good exercise seeing just how cheaply we can make one of these guys for.... it's the sonics that count and if I can get £800 worth of sound for around £30 tops then that's a job well done.

Juices have started to flow here again.... watch this space I'll be back.... off to order an enclosure now

[Deleted]

Mike
I suppose that's the only Suntan you get in far north Scotland these days ? ;D
SandyK

P.S. Those KC5418 kits make great general purpose little regulated supplies. You only need to change (in most cases ) a single resistor value to get a different output voltage. (further info on Jaycar ,or Semi Manufacturers web sites) I used another one of these modules a couple of days ago in a new power supply incorporating a JLH PSU Addon to supply my X-DAC V3. I find it very handy to keep one aside for future use.

[pagan]

Sandyk
Or use trimpots, and make them a variable psu....

[Deleted]

On the PSU, I wonder why two of the heatsinks are vertical and the heatsink on the 5v regulator is horizontal?

I would guess the vertical ones are more efficient.

regards
Greg

[FritzS]

admin said:

Must get some better quality pictures, my rechargeable batteries keep running flat and the camera does not like flat batteries, takes some right old blurry photos.
Alex, I have the LM4562 and will try it along with a few more once I get this puppy up and running, still waiting for the toroidal to arrive.... have a stash of RK27 (blue Velvet) 50K log pots and will probably source the enclosure from Audiokit.it..... I doubt the amp will stay stock for long but you are pretty limited in what you can fit as the pich / pads are pretty small in places and not much room to fit mama honkers..... NICE looking amp for the money though, may just do an all in one enclosure and I have a couple of Clairtronic 15 - 0 - 15V encapsulated trannies should I decide to go that route instead of the toroidal..... maybe a nice mu-metal enclosure for the encapsulated too

It will be a few days before I do more but will keep the thread alive....... you going to try one Leo?

.... and how sounds the amp? Similar to Solo?

[PinkFloyd]

fritzs said:

admin said:

Must get some better quality pictures, my rechargeable batteries keep running flat and the camera does not like flat batteries, takes some right old blurry photos.
Alex, I have the LM4562 and will try it along with a few more once I get this puppy up and running, still waiting for the toroidal to arrive.... have a stash of RK27 (blue Velvet) 50K log pots and will probably source the enclosure from Audiokit.it..... I doubt the amp will stay stock for long but you are pretty limited in what you can fit as the pich / pads are pretty small in places and not much room to fit mama honkers..... NICE looking amp for the money though, may just do an all in one enclosure and I have a couple of Clairtronic 15 - 0 - 15V encapsulated trannies should I decide to go that route instead of the toroidal..... maybe a nice mu-metal enclosure for the encapsulated too

It will be a few days before I do more but will keep the thread alive....... you going to try one Leo?

.... and how sounds the amp? Similar to Solo?

I haven't hooked it up yet Miguel, waiting for the enclosure to arrive.

[pagan]

gregerskine said:

On the PSU, I wonder why two of the heatsinks are vertical and the heatsink on the 5v regulator is horizontal?

I would guess the vertical ones are more efficient.

regards
Greg

I thought about that too, Greg
The +5v reg is for the relays and pic etc, not much power needed.

The +/-15 used for audio analogue parts which include preamp headphone amp.

But why lay the +5v reg down??
Aesthetic value?

allan

ps also speaking to Alex today......
the +5v could be changed for +6v or 8v or 12v or any fixed reg value under the supply voltage.....

[rossman]

I've only today got round to populating the PCB and it was an absolute breeze taking me 25 minutes (and that was going slow) a nine year old could do it, so there you go Rossman get your credit card out and order one from jaycar

Thanks for the reassurance Mike. Looking at the pics it does seem as though it will be easy to assemble, either that or I could get my 9 year old to do it. It will make a nice first project for me. Off to Aus in less than 3 weeks now so I will pick one up at the Hornsby Jaycar store

[Deleted]

rossman said:

[
Off to Aus in less than 3 weeks now so I will pick one up at the Hornsby Jaycar store

Hey, that's our neck of the woods. ;D

[dc]

I don't know where you'll be staying but there's Jaycars all over the place.

www.jaycar.com.au/stores.asp

[rossman]

dc said:

I don't know where you'll be staying but there's Jaycars all over the place.

www.jaycar.com.au/stores.asp

I'll be in Berowra, as far as I can see Hornsby will be the nearest store.

[PinkFloyd]

I had a spare couple of hours there so decided to do an initial "fit" into an el cheapo ABS Maplin enclosure..... I know Jaycar recommend a metal enclosure but I had this one to hand so to hell with it! If it sounds like shite in the ABS enclosure it'll be a simple case of transferring it over to a full metal jacket enclosure.

I've actually used an old Clairtronic encapsulated 12V 30VA transformer which measures 16.4V under no load!! so well up to the job of supplying the necessary 15V IMO.... hooked up the PSU section and all measures perfectly. I will be covering the clairtronics with a tailor cut corned beef tin..... not mu-metal but free and you can also eat the corned beef on a sandwich whilst you're skillfully hacksawing the tin

I'm not sure whether to add an on / off switch and a LED, may well just keep this a no strings attached bare bones amp.... comments welcome from alex who has already built one of these. The onboard phono sockets will be removed and I'll hook up to the chassis mount sockets on the rear panel.

I've fitted the obligatory class X2 cap across the line but may substitute the IEC / X2 with a fully fledged schaffner IEC filter at a later date, I may also add a switchable crossfeed filter and make one of the headouts suitable for low Z 'phones and the other for high Z 'phones.....

This really is an AMAZING kit for the money..... £8 for the amp kit, £5 for the PSU kit, £10 (or thereabouts) for the transformer and £8 for the enclosure.... add another £10 for the pot (ALPS RK27) and chassis mount phono sockets and we are talking £31 all in (that's assuming you own a soldering iron, solder, tools and a few bits and bobs kicking about the joint) seriously guys just LOOK at what you get for your money and ask yourself the question "does a £500 Graham Slee Solo look like a cheap arsed toy compared to this?"

DIY is wonderful (even to an over exposed bugger like me) I still get a woody when all the soldering and casework has been done and still smile like a Cheshire cat if the thing fires up first time (usually does - touchwood!) As I said earlier in this thread..... I don't "need" to fire this amp up, I can tell just by looking at it that it's pretty bullet proof and has the potential to be tweaked to hell and back.

Once again SandyK....... thanks for bringing this most enjoyable to build and extremely reasonably priced little gem to our attention. I look forward to hearing it as soon as I've hooked her up tomorrow..... room in the enclosure for X-Feed (I've got about 20 of them in a box somewhere ready made up ) any other suggestions most welcome.

Actually.... the more I look at this el cheapo Maplins enclosure the more I like it! plenty of ventilation, numerous mounting combinations, easy to machine, cheap, easy to gain access to the boards........

Miguel, if you're reading this the Millet is progressing and you won't believe your eyes when you see it finished Not one of my build it in a day jobs, this is something pretty mind blowing.......

anyways.... state of play with Jaycar kit is thus......

[Deleted]

Mike
Nicely put together. Jaycar also stocks cases like that, but the one shown with the speaker cut out in the bottom is no longer stocked.

Other members.
Please note that this is a mock up for test purposes. Never use exposed mains fuses and terminals as Mike has done in this prototype, UNLESS , like Mike and several other members, you are experienced DIYers. The final version that Mike presents, will look the part, and meet his usual high safety standards. Mike's final version will be using a toroidal transformer, so do not worry about the need for perf board construction that Mike has used for the present setup. I imagine that the final version will also feature the tasteful front panel purple LED as well.
SandyK

[leo]

She's coming on nicely Mike!
I actually built one of my first dacs in one of those Maplin enclosures, , ok not fancy looking aluminum etc but I thought it looked and served its purpose well IMHO

This amp should sound decent as standard and nice and ripe for modding for later

[Deleted]

Leo
Enough room for 2 original JLH boards stacked one above the other ? Current limiters removed,of course, and Q4 upgraded to a BD139/BD140.
Alex