41Hz Amp6 BASIC minireview

kristleifur · 15th October 2008, 11:38 AM

Hi,

I just finished an 41hz Amp6-BASIC. The build was super quick, basically too easy to be challenging. The amp sounds great, I can't tell a difference between Amp6 and Amp6-BASIC. I found a 12V 2A SMPS lying around and it fit the included connector and I was up and running in minutes.

Sound: Very clear all around and full and rigid bass, even with pretty bad ghettoblaster loudspeakers. Much better sound with bad no-name speakers + Amp6B than good KEF speakers and a basic NAD receiver. The sound is so stiff! It's ridiculous how this tiny, cool-running amp controls the speakers SO much better than any other amp I've heard. With even the cheap, simple Amp6-BASIC, the audio quality bottlenecks in my system has definitely become the source - not the amp or speakers really. This is no news to those that have heard good Class-D amps, but still, experiencing it is great, every time.

I like the ready-wound inductors in the BASIC model, very easy to solder.

Positives -
Ridiculously easy build, everything is in bags and the bags are numbered and ordered. Open bag, solder stuff on. Next bag.
Everything is included - jacks, terminals, fuse, bla - everything but the case and power supply.
The sound!
The impressiveness factor is huge. Flatmates are hugely impressed that I knocked a whole amplifier together in a couple of evenings after work, and they can definitely tell the difference in the sound.
Musicality! People's favorite music is even more lovely with this amp. What is removed was unneeded, what is added is goodness.

Negatives -
I think the default gain is a bit too high, I'll probably lower it a bit. (Resistors for lower gain are included in the kit.)
I don't think I'll be using the built-in minijack audio-in, and probably not the supplied power connector either.
It's a bit hard to case the amp with the default jacks - I want to use a BIGGER case than the jack locations on the PCB call for.
I'd like to have status LEDs included.
The input caps could be easier to replace with nicer, bigger ones. (It's easy if you omit the minijack input, so that's OK by me.)

None of these flaws are significant drawbacks, just amp personality.

For a beginner, the Amp6-BASIC is perfect, though I'd personally take an Amp6 with the ready-wound inductors as a perfect easy-build amp.

Next up for me, a couple of Amp11 monoblocks. I ancticipate that these will sound better - and they have none of the "negatives" I mention in this review.

Thanks to everybody who has written about audio DIY! Hints, tips, help, instructions, howtos, etc. etc.

454Casull · 16th October 2008, 06:02 AM

Did you put in a volume control or are you running it from a pre-amp or source with volume control?

kristleifur · 16th October 2008, 09:23 AM

No volume control yet, using iPod / preamp / computer volume control.

454Casull · 17th October 2008, 08:13 PM

My [non-basic] kit just came in. I can't get 39 turns out of my windings... they look pretty tight, but I'm missing a HELL of a lot of wire - I'm supposed to have 6cm ends but I'm short by 3-5 windings. Do I just suck that much or has somebody ever got short wires? I forgot to measure the two that I put on, but the third was about 74.5cm.

kristleifur · 17th October 2008, 08:25 PM

I had some trouble with those in my Amp6 - there are some sleight of hand tricks that are not obvious but aren't that hard to do once you know about them. I gently clamped the toroids and "pushed" the wire tighter on for extra tight windings - the wire curved only where the toroid curved, no slack around the straights. IIRC, there are some good instructions at the 41Hz forums, in some thread somewhere. I think those forums actually have the highest concentration of toroid-winding experts anywhere in the world

Also, I think I recall some prewound toroids being available if you don't feel like winding toroids. I remember that after my Amp6 build, I swore that I would never wind my own toroids ever again …

454Casull · 20th October 2008, 07:33 AM

I just snapped one of the wires.

I am quite disappointed.

kristleifur · 20th October 2008, 10:45 AM

Prewound inductors that fit the Amp6 holes may be available ...

Here's something (though in ltd. quantities) at Digikey:
http://search.digikey.com/scripts/Dk...name=P13503-ND

Datatronics seem to make some too:
http://www.datatronics.com/pdf/tripath_inductors.pdf

Here's a couple threads w/ some clues at the 41Hz forums:
http://www.41hz.com/forums/topic.asp?TOPIC_ID=1623
http://www.41hz.com/Forums/topic.asp?TOPIC_ID=1033

Edit - note that this is all worth it in the end. Promise.

lineup · 20th October 2008, 10:55 AM

they ought to sell wires with a length
that has a good margin

after all, 10-20 cm of such wire is no big cost for a company
and nothing compared to overall price of a kit

454Casull · 25th October 2008, 10:40 PM

ahahhhhh

I soldered the bulk electrolytic in the wrong way because of the mis-printed positive sign which ended up as a negative. Then I had to get it out.

I then resoldered it on the bottom side of the board. Yeah, I'm an idiot.

Got a good laugh out of this, though. Hope the extra heat cycle doesn't damage anything.

454Casull · 26th October 2008, 12:24 AM

http://www.dealextreme.com/details.dx/sku.1456

Lucky I have this. All of you should pick this up - gets really hot, and is a fairly classy lighter to boot. Feels well-built in the hand.

15th October 2008, 11:38 AM	#1
kristleifur diyAudio Member Join Date: Apr 2006 Location: Reykjavík	41Hz Amp6 BASIC minireview Hi, I just finished an 41hz Amp6-BASIC. The build was super quick, basically too easy to be challenging. The amp sounds great, I can't tell a difference between Amp6 and Amp6-BASIC. I found a 12V 2A SMPS lying around and it fit the included connector and I was up and running in minutes. Sound: Very clear all around and full and rigid bass, even with pretty bad ghettoblaster loudspeakers. Much better sound with bad no-name speakers + Amp6B than good KEF speakers and a basic NAD receiver. The sound is so stiff! It's ridiculous how this tiny, cool-running amp controls the speakers SO much better than any other amp I've heard. With even the cheap, simple Amp6-BASIC, the audio quality bottlenecks in my system has definitely become the source - not the amp or speakers really. This is no news to those that have heard good Class-D amps, but still, experiencing it is great, every time. I like the ready-wound inductors in the BASIC model, very easy to solder. Positives - Ridiculously easy build, everything is in bags and the bags are numbered and ordered. Open bag, solder stuff on. Next bag. Everything is included - jacks, terminals, fuse, bla - everything but the case and power supply. The sound! The impressiveness factor is huge. Flatmates are hugely impressed that I knocked a whole amplifier together in a couple of evenings after work, and they can definitely tell the difference in the sound. Musicality! People's favorite music is even more lovely with this amp. What is removed was unneeded, what is added is goodness. Negatives - I think the default gain is a bit too high, I'll probably lower it a bit. (Resistors for lower gain are included in the kit.) I don't think I'll be using the built-in minijack audio-in, and probably not the supplied power connector either. It's a bit hard to case the amp with the default jacks - I want to use a BIGGER case than the jack locations on the PCB call for. I'd like to have status LEDs included. The input caps could be easier to replace with nicer, bigger ones. (It's easy if you omit the minijack input, so that's OK by me.) None of these flaws are significant drawbacks, just amp personality. For a beginner, the Amp6-BASIC is perfect, though I'd personally take an Amp6 with the ready-wound inductors as a perfect easy-build amp. Next up for me, a couple of Amp11 monoblocks. I ancticipate that these will sound better - and they have none of the "negatives" I mention in this review. Thanks to everybody who has written about audio DIY! Hints, tips, help, instructions, howtos, etc. etc.

20th October 2008, 10:55 AM	#8
lineup diyAudio Member Join Date: Dec 2005 Location: the north	they ought to sell wires with a length that has a good margin after all, 10-20 cm of such wire is no big cost for a company and nothing compared to overall price of a kit __________________ lineup

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
power supply for 41hz amp6 basic	bull041161	Class D	3	27th April 2009 09:44 PM
41HZ Amp6 basic built by Tim Rawson	xecluded	Swap Meet	5	8th August 2008 11:17 PM
Volume control for 41hz Amp6 Basic	rca9449	Class D	10	14th June 2007 03:20 PM
41Hz amp6 problem	sharpi31	Class D	2	7th February 2007 10:37 AM
41Hz Amp6	cadbike	Class D	9	8th January 2006 04:30 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

16th October 2008, 06:02 AM	#2
454Casull diyAudio Member Join Date: Jan 2004 Location: Toronto, ON, Canada	Did you put in a volume control or are you running it from a pre-amp or source with volume control?

16th October 2008, 09:23 AM	#3
kristleifur diyAudio Member Join Date: Apr 2006 Location: Reykjavík	No volume control yet, using iPod / preamp / computer volume control.

17th October 2008, 08:13 PM	#4
454Casull diyAudio Member Join Date: Jan 2004 Location: Toronto, ON, Canada	My [non-basic] kit just came in. I can't get 39 turns out of my windings... they look pretty tight, but I'm missing a HELL of a lot of wire - I'm supposed to have 6cm ends but I'm short by 3-5 windings. Do I just suck that much or has somebody ever got short wires? I forgot to measure the two that I put on, but the third was about 74.5cm.

17th October 2008, 08:25 PM	#5
kristleifur diyAudio Member Join Date: Apr 2006 Location: Reykjavík	I had some trouble with those in my Amp6 - there are some sleight of hand tricks that are not obvious but aren't that hard to do once you know about them. I gently clamped the toroids and "pushed" the wire tighter on for extra tight windings - the wire curved only where the toroid curved, no slack around the straights. IIRC, there are some good instructions at the 41Hz forums, in some thread somewhere. I think those forums actually have the highest concentration of toroid-winding experts anywhere in the world Also, I think I recall some prewound toroids being available if you don't feel like winding toroids. I remember that after my Amp6 build, I swore that I would never wind my own toroids ever again …

20th October 2008, 07:33 AM	#6
454Casull diyAudio Member Join Date: Jan 2004 Location: Toronto, ON, Canada	I just snapped one of the wires. I am quite disappointed.

20th October 2008, 10:45 AM	#7
kristleifur diyAudio Member Join Date: Apr 2006 Location: Reykjavík	Prewound inductors that fit the Amp6 holes may be available ... Here's something (though in ltd. quantities) at Digikey: http://search.digikey.com/scripts/Dk...name=P13503-ND Datatronics seem to make some too: http://www.datatronics.com/pdf/tripath_inductors.pdf Here's a couple threads w/ some clues at the 41Hz forums: http://www.41hz.com/forums/topic.asp?TOPIC_ID=1623 http://www.41hz.com/Forums/topic.asp?TOPIC_ID=1033 Edit - note that this is all worth it in the end. Promise.

25th October 2008, 10:40 PM	#9
454Casull diyAudio Member Join Date: Jan 2004 Location: Toronto, ON, Canada	ahahhhhh I soldered the bulk electrolytic in the wrong way because of the mis-printed positive sign which ended up as a negative. Then I had to get it out. I then resoldered it on the bottom side of the board. Yeah, I'm an idiot. Got a good laugh out of this, though. Hope the extra heat cycle doesn't damage anything.

26th October 2008, 12:24 AM	#10
454Casull diyAudio Member Join Date: Jan 2004 Location: Toronto, ON, Canada	http://www.dealextreme.com/details.dx/sku.1456 Lucky I have this. All of you should pick this up - gets really hot, and is a fairly classy lighter to boot. Feels well-built in the hand.