41Hz AMP10, Need Advice

[nfm]

Hello everybody,
I tried searching and lurked roughly a week here, I'm pretty new to DIY amps so I'm pretty overwhelmed at this point.

I've been looking at AMP10 and it seems perfect for my needs, I will be using 2ch Behringer B2031P speakers and Auzen X-Fi Prelude sound card. I have pretty good soldering skills:


Some BG NX/FK, Panasonic FM & Rubycon ZLH caps (few mods such as bypassed coupling caps, card sounds awesome), I'm still awaiting OPA637BP OP-AMPS, I fried last pair by accident .

I don't quite understand this, I read info on AMP5 but it notes at the bottom of the page that lot of parts are not included such as transformers or volume knobs. So I choose AMP10.

Beside the enclosure, what else do I need after I assemble the AMP10 kit? I believe there are spots to solder my speaker cables, same goes for power cable or do I need AC to DC transformer? How would I adjust the volume, via potentiometers on the PCB? How does this amp compares to let's say Yamaha HTR-6130 receiver?

Thanks!

[kristleifur]

Hi, here's some info from the Amp10 assembly instructions - you can also download these for yourself when you've placed an order at 41hz.com:

Optional components
The following will at some stage be needed to complete the amplifier, but is not included in the kit:
Transformer. A toroid with a nominal voltage of +/-18VAC to +/-24VAC is recommended. More about this can be found later in this manual.
Fuse. The fuse should not be higher rated than the transformer maximal nominal load.
-Heat sink. Screws and heat conductive paste to mount the
heat sink. -It is recommended that you solder hookup wires to the board.
Optionally you can fit
Screw / solder terminals.
A mute/un-mute switch is recommended for thump-less power-on. You can wire this to a switch on your panel. Optionally use a 2.5 mm jumper (50 mil) on the board.
-You can optionally fit a volume control chip DS1802 on the board.

You'll need a fuse holder for the fuse I think, and an IEC power cord port. And a case

Try to obtain a copy of the instructions as soon as you can. I also recommend getting an Amp32 or Amp6-BASIC to start with to get a feel for things when doing a ground-up build with case, heatsink, power connections etc. etc. - they're dirt cheap, sound great, and make great gifts.

Edit - I think you can use a simple pot before the input stage to control the volume, but I'd get a buffered pot or use a preamp for that for max. goodness. You can plan that later.

Edit 2 - I haven't heard the Amp10, but my simple Amp6 has absolutely killed every amp I've compared it with, excepting some very nice custom valve monoblocks, which the Amp6 was approximately on equal footing with. I'd plan the early retirement of the old amp.

Edit 3 - Jeez, it sounds like I'm on the 41Hz payroll. I'd like to state that there is no affiliation. I only like the amps A Lot.

Edit 4 - Too much coffe. One last thing - check out the 41Hz forums too, they're not bad: http://41hz.com/Forums

[nfm]

Thanks a lot .

[pinkfloyd4ever]

Originally posted by kristleifur
Edit - I think you can use a simple pot before the input stage to control the volume, but I'd get a buffered pot or use a preamp for that for max. goodness. You can plan that later.

What do you mean by a buffered pot?

I too have been looking at 41Hz kits, either a 5, 10, or 10B (or maybe a 6 or 6B). I've heard that 41Hz's directions/assembly instructions are pretty crappy though (see here), so now I've started looking at gainclone kits from chipamp.com or audiosector...rrrrr, so many choices, so little time (and money, even as cheap as these are)

[kristleifur]

Originally posted by pinkfloyd4ever


What do you mean by a buffered pot?

Basically a very small preamp That may be inaccurate terminology though.

I too have been looking at 41Hz kits, either a 5, 10, or 10B (or maybe a 6 or 6B). I've heard that 41Hz's directions/assembly instructions are pretty crappy though (see here), so now I've started looking at gainclone kits from chipamp.com or audiosector...rrrrr, so many choices, so little time (and money, even as cheap as these are)

The instructions for the Amp3 and Amp6 are not elegant, but they do the job IMO. The "bigger" 41Hz amps' instructions assume that the builder can figure things out from the schematic and BOM. I think it's to scare off newbies - not that I necessarily agree with that.

[pinkfloyd4ever]

ahhhh http://www.firstwatt.com/downloads/B...r%20Preamp.pdf

http://www.enjoythemusic.com/diy/070...eamplifier.htm
B1 Buffer Preamp Think it can be done on perfboard? Don't know if it matters, but he's got alot of ground plane on his PCBs. Guess I'll ask on the thread

or how about an OptiVol?

[pinkfloyd4ever]

ok, another question: How do the Amp10 (not 10-Basic) and the other 41Hz amps without output relays have over/under voltage protection, as well as over current and temp protection...is there an internal relay in the Tripath chip? If so, what's the advantage of the output relay on the Amp5 and Amp10-Basic?

[kristleifur]

Interesting preamp!

(Can't comment on the relays ...)

[pinkfloyd4ever]

nfm,
I've been reading alot on the 41hz forums the last few days, and I'd say the 10 is not exactly a newb project. I'd go with the 6-Basic, its build instructions are supposed to be great, wheras the 5 and 10 give some semi-veterans problems. Like others said, their support leaves much desired (you shouldn't need much for the 6B tho), however I'm not sure I'd agree it's to scare newbs There have been many reports of parts missing from kits and Jan (the guy who essentially is 41hz) ignores their emails and/or the contact links on the site don't work. Fortunately he sure as hell can design (more than) one hell of an amp. Plus the Amp6 is probably more often than not called the best sounding 41hz amp; in fact I'm now considering it a little more than the 5/10/10b

[nfm]

pinkfloyd4ever, kristleifur, thanks a lot guys. I not sure if 25W per channel would be enough. My speakers are 150W RMS 4 ohm and I like to occasionally max out my current 2x100W amp .