amp15 picture thread

[V-bro]

Some more pics of different output resistors:


The goo you see here and there is silicone glue I've added to make sure the washers stay in place...





There's a thread about this here:
http://41hz.com/forums/topic.asp?TOPIC_ID=2479

------X-max. can be several meters on any driver, too bad it can be done only once...------

[djQUAN]

I think you should put some insulation between the copper buss bars that cross over each other. with a bit of vibration and a little time, they will rub and wear out the thin enamel insulation and short then blow up.

[Jan]

Great postings Mikechw!

With the test I did, using default gate resistor value,
with / without diode, the THD went down from
around 0.008% with 80nS to around 0.005% with 40nS.
After a few minutes a FET fried.... Using 2.2 ohm
resisors should be fine, as the gate charge with
these FETs are very low. However, EMI may go up
with faster switching. With these small resistance
values and very low gate charge FETs the diodes may / may
not make a difference. Probably very fast
switch diodes type 1N4148 or similar schottkys
would be a good choice. Average current trough the
diodes will be very low, peak current may be more than
the nominal 100mA for these diodes. 1Amp ultra-fast
diodes may be to slow! to make a difference, as
the conduction will happen in a few nano-seconds.
(btw in one nS, light will travel 30cm/1 foot.
We are close to the physics limits...)

VN10 current should not go up at full power, as
average switching frequency tends to go down at high
power. If current goes up, is a sign of shoot-through.

Input caps; there is large space on the PCB for caps
of your choice. Caps with up to 38 mm spacing will fit.
I generally include fairly "standard" input caps, which
do not influence the price (or sound???) of the kits
much. Large polyprop caps of at least 2.2uF or "boutiqe"
caps would increase the kit price significantly.
And people tend to have very different views on which
are the best. So instead, I provide decent standard caps
and lots of space for caps of your own, if you want to
experiment.

[mikechw]

Hi Jan,

Yes, I think the price for 41hz amps are good.
The whole idea of DIY is to enjoy the process of making and trying out.

I enjoyed both your kits and writing on this forum very much.
Its a great place to learn stuffs about audio.
Thanks Jan....

[more10]

Focus on all the components! Its because a tilt(/shift) bellows was used. My friend Per did the shift/tilt modification of a regular bellows:

[V-bro]

Nice picture/setup Morten! []

------X-max. can be several meters on any driver, too bad it can be done only once...------

[extremewillis]

Here is my finished Amp15 in a case. I must say I'm proud of it. I included RCA inputs and also 1/8" input from an iPod. Also a silver volume control and white LED on the front.

http://www.flickr.com/photos/37185294@N08/3513480604/

http://www.flickr.com/photos/37185294@N08/3512673295/

http://www.flickr.com/photos/3718529...n/photostream/

AMP15 sound awesome! definitely my favorite after building AMP10 then AMP1B.

Thanks, Aaron

[more10]

Nice build Aaron!

[more10]

Im building an amp15 for a friend. I am using a Schroff 19" Multipac Pro, http://se.farnell.com/schroff/20860-...80d/dp/1370441.

The box comes without top and bottom, so I bought two COVER PLATEs http://se.farnell.com/schroff/30860-...in_merch=true&, and one CHASSIS PLATE, http://se.farnell.com/schroff/20860-...70d/dp/1370460.

Front, back, top and bottom is 1 mm aluminium, maybe a bit too weak. The chassis plate is 2mm and is sturdy enough to mount transformer on.

The amp is mounted on the side of the cabinet in order to transport heat outside the box. The mounting plate is screwed to the Schroff side, and the amp is mounted on the plate. Here are some pictures from when mounting. I still haven't finished the amp, so there is no guarrantee that this is actually working.



Mounting plate mounted on Schroff side.



From the side. Square nuts fits inside Shroff side.



Pinbolt? Don't know what it is called in english. Nylock nuts give nice friction when srewing bolt.



Actic Silver is islolating.



Artic silver beeing spread out thin.



Artic silver same size as insulation.



Insulation on top of arctic silver.



Artic silver on FET.



Artic silver on rectifier and regulator.



Using shrimp tube to hold the bushings when turning the amp.



Brass tube to allow turning the nylock nut.



Mounted amp.



Test setup. First time playing loud. Crap speakers and low output on laptop, can't yet decide if this is a success.



My lab power setup. Had to use car fuses since 2,5 A fast wasn't enough :-)

If you want to download any pictures, this is the original thread: http://www.warp7.se/forum/viewtopic.php?p=15393#15393

[krilli]

Oh man that is useful, more10. Thanks.