Suggestions for a DIY amp

[JustinG]

I'm looking at (along side my NRFD project) making a pair of smallish bookshelf speakers and an amp to run them for my girlfriend this summer. Half the reason is so when I go visit her I don't have to listen to movies on computer speakers. Any suggestions on a pretty easy amp to put together. I can do basic soldering and the like not *great* at it though. I'm good with electrical schematics though. I would have liked to do a small amp/pre amp setup for her (something like a DH101 and DH120) but I think that might be out of the budget for now.
TIA
-Justin

[Max_Andrews]

Pick up one of the pyramid PB440 car amps, I've used it a few times and it sounds nice (tone controls and gain on the amp too). Get a ~5 amp power supply, either one of the pyramid ones from PE, a mini-atx computer power supply, or a 4A switched-mode type used to power hard drives, etc. (I've even run it off a 1A wall wart with success, but you need at least 3A for full headroom). They'll all be around $25. Then some sort of cable to plug in your source. I use a 9 foot dayton RCA to 3.5mm "Y" cable for my ipod. The amp can be pretty easily removed from the blue casing and mounted in a nicer box, just build it around the heat sink and drill holes for the tone controls.

So all together around $60 and you can power it off a stack of batteries of you want to. I've used it many times and it has some serious volume capability, much better than the t-amp at any rate for about the same price.

[JustinG]

That has some promise to it. I do have an extra "Power Linear" or some random brand car amp (2x150 watts supposedly) laying around. Good suggestion.

[AJ]

The LM3886 based chipamps are probably the simplest way to get 40-60w perchannel of power. You can use the boards from <A HREF="http://www.chipamp.com">www.chipamp.com</A> for the separate channels, but you don't need the power supply board. Using a regular bridge rectifier, toroidal transformer from PE, and filter caps is fine.

The only other stuff you'll need is I/O jacks, power switch, volume control, case, and heatsinks - which can be thick aluminum plate or conventional heatsinks.

If your only input is the computer you could just make it a straight power amp with no volume control, and control the volume in the computer.

Being conservative you should beable to do it all under 100$. If you have questions, just ask.

[philiparcario]

Provided Link: yuasa 12 volt sla battery


> That has some promise to it. I do have an
> extra "Power Linear" or some
> random brand car amp (2x150 watts
> supposedly) laying around. Good suggestion.
I have some good batteries if you need them. 12 volt 5ah . i have two of these . dirt cheap price. 35 including shipping. see link

[JustinG]

> The LM3886 based chipamps are probably the
> simplest way to get 40-60w perchannel of
> power. You can use the boards from
> <A HREF="http://www.chipamp.com">www.chipamp.com</A> for the separate channels,
> but you don't need the power supply board.
> Using a regular bridge rectifier, toroidal
> transformer from PE, and filter caps is
> fine.

> The only other stuff you'll need is I/O
> jacks, power switch, volume control, case,
> and heatsinks - which can be thick aluminum
> plate or conventional heatsinks.

> If your only input is the computer you could
> just make it a straight power amp with no
> volume control, and control the volume in
> the computer.

> Being conservative you should beable to do
> it all under 100$. If you have questions,
> just ask.

Thanks AJ I had seen some of their stuff and never really heard anything about it. Not quite sure if I will be needing multiple inputs or not yet. When the time gets closer I'll know more this was just to get an idea of what is out there.

[philiparcario]

> The LM3886 based chipamps are probably the
> simplest way to get 40-60w perchannel of
> power. You can use the boards from
> <A HREF="http://www.chipamp.com">www.chipamp.com</A> for the separate channels,
> but you don't need the power supply board.
> Using a regular bridge rectifier, toroidal
> transformer from PE, and filter caps is
> fine.

> The only other stuff you'll need is I/O
> jacks, power switch, volume control, case,
> and heatsinks - which can be thick aluminum
> plate or conventional heatsinks.

> If your only input is the computer you could
> just make it a straight power amp with no
> volume control, and control the volume in
> the computer.

> Being conservative you should beable to do
> it all under 100$. If you have questions,
> just ask.
I have 3 chip amps built if you are interested phil

[davidvwebber]

> I'm looking at (along side my NRFD project)
> making a pair of smallish bookshelf speakers
> and an amp to run them for my girlfriend
> this summer. Half the reason is so when I go
> visit her I don't have to listen to movies
> on computer speakers. Any suggestions on a
> pretty easy amp to put together. I can do
> basic soldering and the like not *great* at
> it though. I'm good with electrical
> schematics though. I would have liked to do
> a small amp/pre amp setup for her (something
> like a DH101 and DH120) but I think that
> might be out of the budget for now.
> TIA
> -Justin
I have been wondering about tjis one for the same application :

<A HREF="http://www.hobbytron.com/vk4004.html">http://www.hobbytron.com/vk4004.html</A>

These look like nice kits , but I can't figure out which one would be best for small speakers !

<A HREF="http://ampslab.com/products.htm">http://ampslab.com/products.htm</A>

David V. Webber

[JustinG]

"I have been wondering about tjis one for the same application :"

Why are you building my girlfriend a pair of speakers?! Yeah amps have always intrigued me. Once I build something I'll let ya know.

[davidvwebber]

> I have been wondering about tjis one for the
> same application :

> <A HREF="http://www.hobbytron.com/vk4004.html">http://www.hobbytron.com/vk4004.html</A> These
> look like nice kits , but I can't figure out
> which one would be best for small speakers !

> <A HREF="http://ampslab.com/products.htm">http://ampslab.com/products.htm</A> David V.
> Webber

Well , not EXACTLY the same application ;
( but I'll help if needed ! )
No , for Christmas we got a new HP Pavillion
a6320n , which will play DVDs ; and a new " Wide -
Screen " SAMSUNG 206BW Monitor . The present
computer speakers sound ( to me anyway , ) just like a telephone ! So , that is why I'm researching solutions !! David

[philiparcario]

> Well , not EXACTLY the same application ;
> ( but I'll help if needed ! )
> No , for Christmas we got a new HP Pavillion
> a6320n , which will play DVDs ; and a new
> " Wide -
> Screen " SAMSUNG 206BW Monitor . The
> present
> computer speakers sound ( to me anyway , )
> just like a telephone ! So , that is why I'm
> researching solutions !! David
some nice omptimus 7 speakers on ebay would work.

[philiparcario]

> Well , not EXACTLY the same application ;
> ( but I'll help if needed ! )
> No , for Christmas we got a new HP Pavillion
> a6320n , which will play DVDs ; and a new
> " Wide -
> Screen " SAMSUNG 206BW Monitor . The
> present
> computer speakers sound ( to me anyway , )
> just like a telephone ! So , that is why I'm
> researching solutions !! David
I have a pair of audax vp130g2 coaxial speakers from madisound. they would make good pc speakers

[davidvwebber]

> I have been wondering about tjis one for the
> same application :

> <A HREF="http://www.hobbytron.com/vk4004.html">http://www.hobbytron.com/vk4004.html</A> These
> look like nice kits , but I can't figure out
> which one would be best for small speakers !

> <A HREF="http://ampslab.com/products.htm">http://ampslab.com/products.htm</A> David V.
> Webber
Also , this little guy is real cute ! BUT , it is " SMT " ; " Surface Mount Technology " . All the components are REAL TINY and soldered onto the TOP of the board . No wires sticking down through holes to be soldered on the back - side !
I can do it , but I really would prefer not to !
You need a NEEDLE POINT iron , and a magnifier !
If anyone should attempt one of these , please post how it went ! Ha Ha . DVW

[davidvwebber]

> Also , this little guy is real cute ! BUT ,
> it is " SMT " ; " Surface
> Mount Technology " . All the components
> are REAL TINY and soldered onto the TOP of
> the board . No wires sticking down through
> holes to be soldered on the back - side !
> I can do it , but I really would prefer not
> to !
> You need a NEEDLE POINT iron , and a
> magnifier !

<A HREF="http://www.ramseyelectronics.com/cgi...ction&key=UAM4">http://www.ramseyelectronics.com/cgi...ction&key=UAM4</A>
> If anyone should attempt one of these ,
> please post how it went ! Ha Ha . DVW

[daneo]

> I'm looking at (along side my NRFD project)
> making a pair of smallish bookshelf speakers
> and an amp to run them for my girlfriend
> this summer. Half the reason is so when I go
> visit her I don't have to listen to movies
> on computer speakers. Any suggestions on a
> pretty easy amp to put together. I can do
> basic soldering and the like not *great* at
> it though. I'm good with electrical
> schematics though. I would have liked to do
> a small amp/pre amp setup for her (something
> like a DH101 and DH120) but I think that
> might be out of the budget for now.
> TIA
> -Justin

<A HREF="http://www.tubeaudio.com/page23.html">http://www.tubeaudio.com/page23.html</A>

Just a thought...

[davidvwebber]

> I have 3 chip amps built if you are
> interested phil
Would one of your ( 3886 ? ) Chip Amps power one of these :

<A HREF="http://www.partsexpress.com/projects...ct=HiviJuniors">http://www.partsexpress.com/projects...ct=HiviJuniors</A>

TIA DVW

[philiparcario]

> Would one of your ( 3886 ? ) Chip Amps power
> one of these :

>
> <A HREF="http://www.partsexpress.com/projects...ct=HiviJuniors">http://www.partsexpress.com/projects...ct=HiviJuniors</A>
> TIA DVW
yes they have about 35 watts for 8ohm and 60 watts for 4ohm. I purchased a few from tim rawson a diy amp builder on audiogon. They range in price from 140 to 240. mostly due to the case difference or volume control of not. I am getting rid of them because a purchased a 5 channel one. for my tweeters. phil

[davidvwebber]

> yes they have about 35 watts for 8ohm and 60
> watts for 4ohm. I purchased a few from tim
> rawson a diy amp builder on audiogon. They
> range in price from 140 to 240. mostly due
> to the case difference or volume control of
> not. I am getting rid of them because a
> purchased a 5 channel one. for my tweeters.
> phil
Would just one amp be stereo , or do you need a pair ? Are there any photos of similar ones on
Audiogon or any of the chip - amp sites ? DVW

[philiparcario]

> Would just one amp be stereo , or do you
> need a pair ? Are there any photos of
> similar ones on
> Audiogon or any of the chip - amp sites ?
> DVW
I have one with 1 input 2 rca's 2 sets of binding posts. stereo about 8 by 5 by 5. I can send pictures on wed email me at <A HREF="mailtohiliparcario@yahoo.com">philiparcario@yahoo.com</A> it has a volume pot an on off switch and an iec jack color is black.

[philiparcario]

Provided Link: gainclone pic


This is one of the diy gainclones I have It is the smallest one i have.