nearfield power amp schematic

Are there any DIY friendly solutions for a clean and flat stereo power amp to drive passive near field monitors?
i am using a consumer hifi one atm and still have a half functioning ra500 which is out of action indefinitely.

obviously its important for the design to be clean and accurate as possible.
assuming it will be driving something at least like ns10's powerwise

http://www.hypex.nl/
look for the power amp modules UcDxxxxx. These modules are being used in the Bryston 875 and some other reasonable quality amplifiers.

http://www.groupdiy.com/index.php?topic=42999.0

Hypex for sure, and maybe check out the JLM kit for a 60w chip amp:

http://www.jlmaudio.com/shop/index.php?_a=viewProd&productId=18

One per channel, plus a torroid and a rectifier, and you're good to go.

JAB said:

Hypex for sure, and maybe check out the JLM kit for a 60w chip amp:

http://www.jlmaudio.com/shop/index.php?_a=viewProd&productId=18

One per channel, plus a torroid and a rectifier, and you're good to go.

Click to expand...

or you could just buy the chip for £5 each & roll your own to make it even cheaper !

There are some naim 140 pcbs on the bay

http://cgi.ebay.com/50W-amplifier-PCB-Naim-140-/220503323781?pt=LH_DefaultDomain_0&hash=item335705b485

I got a pair as a kit a while back to power my nearfields still working on them...but with leave that little chip in the dust I imagine!

good options, cheers guys
hypex looks pretty flawless.

the last one looks like fun.
how do you think this will compare to the £100-£300 range of budget reference amps?
the sound is obviously subjective but i cant find any stats on the last one,

I've never had the opportunity to hear an actual naim 140 or even a clone.
From what I've found online they are very highly regarded in some circles. Someone with more (any) ear on experience would shed some more light.

But naim still exists today. I remember when I decided on what pcb to buy doing my research and feeling very confident that the naim 140 was a great choice.

powered with +/-40v give 75w which is just what I need.

http://www.audioreview.com/cat/amplification/amplifiers/naim/nap-140/PRD_116028_1583crx.aspx

While I have never heard the Hypex myself, I have a lot of respect for the designer and heard mostly good things about it.

JR

Hi,



  I might be wrong, but I think I remember someone saying that Hypex are used in Bryston Amps. Please do not shoot me if I am wrong . . . . . . .

Hey Kev,

Ruairi is selling a pair on Black Market

http://www.groupdiy.com/index.php?topic=42999.0

However, they are apparently in US so it probably makes sense to get them from Europe otherwise you'll pay import duty.

I had been given a pair of UCD 250 complete with the PSUs that are still waiting to be cased and tested. These were early production samples.

ha yea,
funnily enough i just posted about damn customs elsewhere.

even still, that would be about 6-10x my budget for the amp anyway

i'm weighing up the options, i'll have another go fixing the ra500(£150value tops) when i get some more funds and see how it performs but i was thinking about maybe using the chassis for a more accurate but less power diy monitor amp.
or just start from scratch. i have some old omar monitors which i consider to be very good/flat but have never had a good amp for monitors before, just need to jump in somewhere so i'm gauging differences.

Kepeb,

I gotta say I was remarkably ignorant of the difference a good power amp can make to any speaker for years.  I always imagined that if it was rated for the right amount of watts I'd be good, not so.  Have you ever heard NS-10s with a good amp?

I've gotta say those Alesis amps are pretty rotten, the old Samson ones that were so popular about the place are worse.  Do yourself a big favour and find the extra money to pick up a pair of the cheapest Hypex modules, the UCD180. If you are handy you might be able to rework the PSU from your broken Alesis, if not just give in a get the SMPS180.  You will not believe the sound of these modules for the money.

Good monitoring is everything.

Good luck.

Ruairi

hey ruairio,
appreciate the input, 

had a look on ebay and the prices for 180's seem more appropriate for my level 

theres st or hg (high grade) versions with differences that i cant see but i cand see myself needing more power than that.

are the blue T shapes all the heatsinking they need?
if so i think this monster 3U alesis chassis would be massive overkill

Kepeb,

Like I said, years I ago I would've said an amp is an amp but now I realise they are worth spending money on.

Glad you found some good deals on the 180s, I bought the HG version when I got my 400s but the differences must be subtle?  I never compared...

They do need heatsinking - as efficient as they are (92%) they are still dissipating watts when driven hard.  I think a big chassis on a power amp feels good,even if the module is the size of a postage stamp 

Good luck and please report back.

Cheers,
Ruairi

I agree about those Samson amps, they are really mushy.  I swapped from one of those to an old HH amp like this

http://cgi.ebay.co.uk/HH-Electronics-v200-Mos-Fet-Amplifier-/200572856501?pt=UK_MusicalInstr_Amplifiers_RL&hash=item2eb312e8b5

The clarity was a night & day difference.  Pretty much any of that series of HH amp is pretty good, the 1U VX150 is great for nearfields.  & They aren't a fortune.

cant get that one to load...

EDIT: ah, tis now

works here

Sredna said:

http://www.41hz.com

Click to expand...

I was looking at the similar... so anybody here has any direct listening experience with Tripath TA3020 chips?

Best, M