NVA AP30 boards [Archive] - The Art of Sound Forum

r100

11-11-2014, 21:24

http://www.digikit.ca/NVA-AP-30-Amplifier-Kit-Assembled.html

Has anyone built an amp with them ? I had a "real" AP30 and was very fond of the sound it produced so it would be quite interesting to build one for fun if these boards are any good.

istari_knight

11-11-2014, 21:58

Those boards use the same circuit but with different layout, from my experience playing with Naim clones I would say they might sound similar to the originals but not the same. These are much closer copies that look much more worthwhile if you are seriously going to buy some: http://www.ebay.co.uk/itm/300921899784?ssPageName=STRK:MESINDXX:IT&_trksid=p3984.m1436.l2649

Personally I wouldn't be too eager to rip them off on moral grounds, okay so I did it with Naim but they are a relatively large company who "borrowed" the design themselves from an RCA textbook whereas these are basically stolen IP from a one man band who has to earn a living from it... Not cool :(

walpurgis

11-11-2014, 23:50

Personally I wouldn't be too eager to rip them off on moral grounds, these are basically stolen IP from a one man band who has to earn a living from it... Not cool :(

Fair point. I agree with your view James.

awkwardbydesign

12-11-2014, 09:46

Personally I wouldn't be too eager to rip them off on moral grounds, okay so I did it with Naim but they are a relatively large company who "borrowed" the design themselves from an RCA textbook whereas these are basically stolen IP from a one man band who has to earn a living from it... Not cool :(
Interestingly, I think copyright law allows you to make one for your own use, but not for commercial gain. So if you buy a commercial copy from a Chinese source, are you breaking the law? I am only referring to the legal aspect, not the morality of it. I have cloned several pre-amps (for my own use), but I etched my own boards. I still have a Concordant clone that I must revive one day.

r100

12-11-2014, 13:01

[emoji15]

Sovereign

12-11-2014, 13:18

Personally I wouldn't be too eager to rip them off on moral grounds, okay so I did it with Naim but they are a relatively large company who "borrowed" the design themselves from an RCA textbook whereas these are basically stolen IP from a one man band who has to earn a living from it... Not cool :([/QUOTE]

I may be wrong, but I believe the circuit boards found in NVA amps does not exclusively belong to NVA. Personally, with the fantastic sound of NVA amps and the service and 'upgradeability' you get from NVA amps I would just by an NVA amp, then you know you have the real deal and NVA are always more than willing to service their amps.

r100

12-11-2014, 13:30

oops the poor man... any alterative (a/b ss) DIY kit with similar characteristics that can be bought freely, legally, without causing a flood of trolling and without ripping off a small UK manufacturer ? I would like to assemble myself not buy a finished product, thanks

Oldpinkman

12-11-2014, 13:31

There is no copyright on circuit designs. You can patent an idea - but that only lasts for 17 years. It was one of the reasons we resorted to potting the DaCapo circuit at Pink Triangle.

awkwardbydesign

12-11-2014, 13:44

There is no copyright on circuit designs. You can patent an idea - but that only lasts for 17 years. It was one of the reasons we resorted to potting the DaCapo circuit at Pink Triangle.
But can you copyright the exact layout?

r100

12-11-2014, 13:49

if there is an original idea behind it most probably

DSJR

12-11-2014, 14:09

Nothing like 'em!

r100

12-11-2014, 14:36

hmm, yes, of course .. but not sold as a kit are they ?

:rolleyes:

Sovereign

12-11-2014, 15:14

I have an NVA circuit board in front of me, the copied boards look nothing like what I have, but then i'm not electronics engineer!

Ali Tait

12-11-2014, 15:18

I think things like layout and grounding routes have as big an impact as anything on the final sound of an amp.

r100

12-11-2014, 15:20

did you open the case Sov ??
:uhho:

r100

12-11-2014, 15:21

I think things like layout and grounding routes have as big an impact as anything on the final sound of an amp.

Yep, thank's. That is what I have learnt from this thread. Thank's Ali.

Ali Tait

12-11-2014, 15:22

did you open the case Sov ??
:uhho:

:lol:

Sovereign

12-11-2014, 15:27

did you open the case Sov ??
:uhho:

It's been open a while

r100

12-11-2014, 15:32

oh ok :interesting:

what about these amps ?
http://www.aussieamplifiers.com
http://www.ska-audio.com
http://www.aksaonline.com

updating list...

Oldpinkman

12-11-2014, 16:04

But can you copyright the exact layout?

Not that I'm aware of. You can copyright the layout of integrated circuit designs I believe but I have no direct experience. My friend relies on patents.

Ali Tait

12-11-2014, 16:35

oh ok :interesting:

what about these amps ?
http://www.aussieamplifiers.com
http://www.ska-audio.com
http://www.aksaonline.com

updating list...

Heard an Aksa a long time ago, it was a nice amp. I'm currently looking at a Krell type board on ebay. Bought a nice heatsinked chassis last week, just deciding whether to go with those boards or not.

istari_knight

12-11-2014, 18:37

I've nothing more to add regarding the NVA boards but will say that if/when I build another amp it wont be based on any British class B guff but a Pass Labs DIY design, something like the F5 ;)

Ali Tait

12-11-2014, 18:42

Good choice, is on my radar too, a fine sounding amp.

r100

12-11-2014, 19:31

I've nothing more to add regarding the NVA boards but will say that if/when I build another amp it wont be based on any British class B guff but a Pass Labs DIY design, something like the F5 ;)

a different class altogether, I assume ? Anyways, as this thread has reached a dead end, here something a little abstract which has nothing to do with amps or hifi.. although, maybe it does ? http://youtu.be/-3JCESdFNyw or http://youtu.be/-0Xa4bHcJu8

:stalks:

r100

13-11-2014, 23:32

Lateral mosfet amp

this project looks very interesting and not to expensive (but probably uses too much electricity)

http://sound.westhost.com/project101.htm

r100

14-11-2014, 23:20

and i think i'll settle for these here which are very cheap, and easy to build.

13514

edit: added this article
http://diyaudioprojects.com/Chip/LM3886_CA/LM3886_CA.htm

Ali Tait

14-11-2014, 23:26

Just bought these, fancy building a SS Class A amp-

http://www.ebay.co.uk/itm/371161583932?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

r100

15-11-2014, 13:10

look nice, looking forward to some pics and notes on the sound ;-)

... now these have some Pass Spirit in them and surely would sound great.. complete kit removes the hassle of sourcing components

http://www.diyaudio.com/store/aca-bundle-210.html

Ali Tait

15-11-2014, 15:05

Aye, looked at those too, out of stock though..

Will put some pics up when I get round to it. Just bought the power supply caps, think I need a bigger chassis...

DSJR

15-11-2014, 17:34

This is probably below your expectations, but how about this?

http://www.bakeraudio.org/baker-hb7-mosfet-amplifier.html

Ali Tait

15-11-2014, 18:26

Cheers Dave, hadn't come across that. I'm after a Class A amp though.

DSJR

15-11-2014, 18:41

walpurgis

15-11-2014, 18:47

what exactly does Class A do these days that more normal amps 'with modern devices' doesn't?

Sound better?

Ali Tait

15-11-2014, 18:57

Mr Kipling

15-11-2014, 19:16

I'm not baiting, but what exactly does Class A do these days that more normal amps 'with modern devices' doesn't? Most MODERN amp designs run in class A at low powers anyway I believe (crosses fingers hard :lol:)

Dave, I was reading this earlier today and found it interesting:

http://www.passdiy.com/project/articles/single-ended-class-a

What this country needs is a designer like Nelson Pass.

Ali Tait

15-11-2014, 19:18

Pass amps are very nice. I'd be building an F5, but have already heard one a few times and wanted to try something new.

Mr Kipling

15-11-2014, 19:26

I like his view on keeping circuity simple. When I look at the innards of some gear I think to myself: "Is all that guff really needed?" Puts me off.

Barry

15-11-2014, 19:36

I like his view on keeping circuity simple. When I look at the innards of some gear I think to myself: "Is all that guff really needed?" Puts me off.

I think the same when I look under the bonnet of my car!

Mr Kipling

15-11-2014, 19:40

I think the same when I look under the bonnet of my car!

Well, not owning one, I don't have that worry!

Sovereign

16-11-2014, 23:29

I want to build a Class A amp as I'm enjoying the Kraken I recently acquired. Nice as it sounds, it's only about 2-4w Class A and I'd like to try an amp with more power.

That and I prefer Class A amps. My ears, my choice. As Geoff says, they sound better. To me anyway.
Hi Ali at some point Colin Wonfor is planing on selling Class A DIY amp kits, I'm not sure how far away this is but I could ask him if you like

struth

16-11-2014, 23:58

brian2957

17-11-2014, 00:46

Aye heard Alis Kraken amp . Very nice indeed .

Mr Kipling

17-11-2014, 00:54

I want to build a Class A amp as I'm enjoying the Kraken I recently acquired…

Do you switch it on or… release it?

13532

Ali Tait

17-11-2014, 08:10

Ali Tait

17-11-2014, 08:15

Hi Ali at some point Colin Wonfor is planing on selling Class A DIY amp kits, I'm not sure how far away this is but I could ask him if you like

Cheers mate, yes was aware, be interested what he comes out with, but I've already bought boards and power supply caps.

Ali Tait

17-11-2014, 08:16

That Kraken is very good Ali. I liked it a lot.

Aye, I was surprised by how good it is. Needs easy to drive speakers though .

brian2957

17-11-2014, 08:22

It seemed to do a very good job with Garys big Edingdales .

Ali Tait

17-11-2014, 08:51

They are very easy to drive. :-)

Ali Tait

18-11-2014, 08:48

Dave, I was reading this earlier today and found it interesting:

http://www.passdiy.com/project/articles/single-ended-class-a

What this country needs is a designer like Nelson Pass.

Yes, he's produced some great designs. He sells stuff commecially under the First Watt brand, not cheap admittedly, but it's his generosity in giving away diy designs for free to the DIY community that is a great thing. All the DIY kit of his designs I've heard has been excellent.

awkwardbydesign

18-11-2014, 12:05

Nelson is an example to other designers. Although some, like John Curl, are happy to help with modifications to their commercial designs.

r100

23-11-2014, 16:32

AKSA designer Hugh Dean reflecting on his designs and the environment in which they are sold... anno 2003. I found it quite interesting. Since then, two new amplifier kits have emerged. The NAKSA 80 / 100.

http://www.diyaudio.com/forums/solid-state/11487-best-sounding-diy-ss-amp-3.html#post134105

r100

14-12-2014, 19:04

QUOTE=DSJR;596797]This is probably below your expectations, but how about this?

http://www.bakeraudio.org/baker-hb7-mosfet-amplifier.html[/QUOTE]

Hi Dave,
I was just re-reading this thread an saw your suggestion which looks really nice. I will check it out in more detail.

In the mean time I settled for a chipamp which I put into a temporary wooden box.

A quick listen did present a nice sound but I'll have to wait a little more for a fuller test until I sort a problem with a DC offset missmatch (there is a build-thread on diyaudio.com (http://www.diyaudio.com/forums/chip-amps/266329-chipamp-com-dc-output-voltage.html) if anyone is interested) and until I'm confident the LM3886 chips won't melt under load :eyebrows: (need proper heat sinks for that)

here a pic of the proto-build.

best

13660

r100

23-12-2014, 19:30

just a quick update. These amps are performing really well. As you can see on diyaudio.com I still have to sort some harshness at high volumes. The great thing with these circuits is that there is an active thread on every aspect of them at diyaudio.com. So tweeking them to specific needs is just a post away. I made the enclosure from Corian - a material that is like MDF but much more monolithic if that makes sense ?? The nice thing about it is that you can glue it very precisely i.e. you can't see the joints which is cool [emoji12]

1368113682a

istari_knight

23-12-2014, 19:36

Looking good Rupert, that chassis looks the part :thumbsup:

DSJR

23-12-2014, 19:52

Hi Rupert. This DIY thing is addictive isn't it :eek: I suppose the added confidence now (needed for 'work') is spurring me on to make a power amp of my own. I've already done an extremely ugly passive preamp (I chose too tall a Hammond grey ABS box and it looks ghastly :lol:) and have the power amp in two halves really for socket holes to be drilled and wired up...

r100

24-12-2014, 00:41

Go for it !!

r100

24-12-2014, 00:44

Looking good Rupert, that chassis looks the part [emoji106]
Thanks man ☺

r100

28-12-2014, 21:54

hi Dave, as long as it sounds good the rest is not so important :) btw. are you happy with the sound ? Is it based on tubes or solid state ? greets

Yep, diy is addictive. Building something that you can actually listen to is great !

Hi Rupert. This DIY thing is addictive isn't it I suppose the added confidence now (needed for 'work') is spurring me on to make a power amp of my own. I've already done an extremely ugly passive preamp (I chose too tall a Hammond grey ABS box and it looks ghastly ) and have the power amp in two halves really for socket holes to be drilled and wired up...

synsei

29-12-2014, 06:38

Just bought these, fancy building a SS Class A amp-

http://www.ebay.co.uk/itm/371161583932?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

I note from the photos that the layout is slightly different for each of these boards, specifically the route of the broad tracks leading to each of the blue modules and the locations of the smaller of the two sets of terminals. There's probably a good explanation for this and so I was wondering what it might be... :)

p.s. Does it show that I'm not technically minded? :lol:

Firebottle

29-12-2014, 07:37

Dave those boards are separate left and right channel boards, built so they are a mirror image of each other.
That way they can be fitted into a case so that the power transistors are to the sides where the L+R heatsinks would be.

The blue modules at the top are the output relays.

:) Alan

istari_knight

29-12-2014, 09:46

IME these Chinese PCB's are every bit as good as the genuine articles they are copied from... Better quality in many cases ! Unfortunately the same cannot be said of the components fitted which are usually crap, often only the diodes are usable.

Better to get blanks & populate with your own components of known provenance / to your own taste - http://stores.ebay.co.uk/jims-audio-store/Bare-PCBs-of-kits-/_i.html?_fsub=1192327015&_sid=26814015&_trksid=p4634.c0.m322

r100

29-12-2014, 18:04

My next build will probably be based on these here (http://www.ebay.com/itm/LJM-Assembled-MX50-SE-Power-amp-kit-Stero-Amplifier-boards-/191265876492?pt=US_Home_Audio_Amplifiers_Preamps&hash=item2c8855aa0c)

LJM-Assembled MX50 SE Power amp kit

LJM is a Chinese amp designer and some of his designs seems to be well regarded. Not much risk for the price.

Mods: Maybe this thread should be renamed to "Cheap amplifier kits" or something like that ?

Ali Tait

29-12-2014, 18:22

I note from the photos that the layout is slightly different for each of these boards, specifically the route of the broad tracks leading to each of the blue modules and the locations of the smaller of the two sets of terminals. There's probably a good explanation for this and so I was wondering what it might be... :)

p.s. Does it show that I'm not technically minded? :lol:

Wot Alan sed!

synsei

29-12-2014, 18:34

Ali Tait

29-12-2014, 18:44

My next build will probably be based on these here (http://www.ebay.com/itm/LJM-Assembled-MX50-SE-Power-amp-kit-Stero-Amplifier-boards-/191265876492?pt=US_Home_Audio_Amplifiers_Preamps&hash=item2c8855aa0c)

LJM-Assembled MX50 SE Power amp ki

LJM is a Chinese amp designer and some of his designs seems to be well regarded. Not much risk for the price.

Mods: Maybe this thread should be renamed to "Cheap amplifier kits" or something like that ?

Looks interesting.

r100

30-12-2014, 21:03

I have just ordered a kit from peter Daniel at audiosector.com
http://www.audiosector.com/lm4780.shtml

After my previous gainclone project I'm interested to compare it to this kit 😜

This kit has hand picked high quality components at a fair price.

I'll have to put the ljm kit on the waiting list until this one is finished.

r100

01-01-2015, 18:35

Just bought these, fancy building a SS Class A amp-

http://www.ebay.co.uk/itm/371161583932?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

hey Ali, happy New Year to you and to all fellow members...

is it built ? if so what is the sound like ?

greets

Ali Tait

01-01-2015, 19:02

Happy New Year to you too.

No not built yet, still need to buy the transformers. Need to get a job first before I do that!

r100

01-01-2015, 20:55

Happy New Year to you too.

No not built yet, still need to buy the transformers. Need to get a job first before I do that!

:lol:

well, hope you find one fast...