Glad you like it, DX. I am really thankful for you ,quasi, self,
pass, etc. Without this forum it would be very hard to get
good results with DIY amps.
As far as cheap (and not ugly) here is a good idea for
DIY amp heatsinks. (30$) for all the poor DIY'ers.....
Zoble is on little board ,too...
and the whole thing....
Will work with no fan for stereo 100w (2 x DX original ,p3a,etc)
with temperature controlled fan (party only or brazil ..30C+)
2 X 150W amps are happy to spit out "fat electrons" all day.
All you need is 2 X 13" (335cm) "L" brackets and 4 cheap P4
heatsink, paste , and hardware/tap.This sure beats 100$/channel
fancypants heatsinks everybody uses at DIYaudio.
Soon I will have the whole doohiggy
done and invite you
to see the prettiest "ugly amp"(frugalamp).
(get your chicks for nuthin' and your amps for free)
Thanks for much inspiration,
OS.
pass, etc. Without this forum it would be very hard to get
good results with DIY amps.
As far as cheap (and not ugly) here is a good idea for
DIY amp heatsinks. (30$) for all the poor DIY'ers.....
An externally hosted image should be here but it was not working when we last tested it.
Zoble is on little board ,too...
and the whole thing....
An externally hosted image should be here but it was not working when we last tested it.
Will work with no fan for stereo 100w (2 x DX original ,p3a,etc)
with temperature controlled fan (party only or brazil ..30C+)
2 X 150W amps are happy to spit out "fat electrons" all day.
All you need is 2 X 13" (335cm) "L" brackets and 4 cheap P4
heatsink, paste , and hardware/tap.This sure beats 100$/channel
fancypants heatsinks everybody uses at DIYaudio.
Soon I will have the whole doohiggy
done and invite youto see the prettiest "ugly amp"(frugalamp).
(get your chicks for nuthin' and your amps for free
)Thanks for much inspiration,
OS.
Here's the real thing for A$29 (that's about US$20)
http://www.altronics.com.au/index.asp?area=item&id=H0542
They are often on "special" and Altronics often gives out $20 gift vouchers. I usually get 4 or 5 to get the quantity discount.
regards
http://www.altronics.com.au/index.asp?area=item&id=H0542
They are often on "special" and Altronics often gives out $20 gift vouchers. I usually get 4 or 5 to get the quantity discount.
regards
Thank you very much , I'll bookmark this. I have searched for
a long time but only found Fischer elect. ,who wants 50-100 for a
HS.
Still ,it's from Australia, and shipping would be high unless I ordered several. also , that heatsink has 24 fins VS. 100+
on my locally available "uglysink".
But , all in all, if I produce many, It might help to have a
premade option available.Would it be less "DIY" to
buy one when you can build one with what is available.??
Is one you build yourself any less "real"... as long as it
can do the same Celsius/watt as the real one. Look at
Carlo's hand drawn amps , they are "real".. in fact, I
copied him to do my boards.
BTW.. the one above only cost 0$ because I picked up
a truck load of DELL's for free.
a long time but only found Fischer elect. ,who wants 50-100 for a
HS.
Still ,it's from Australia, and shipping would be high unless I ordered several. also , that heatsink has 24 fins VS. 100+
on my locally available "uglysink".
But , all in all, if I produce many, It might help to have a
premade option available.Would it be less "DIY" to
buy one when you can build one with what is available.??
Is one you build yourself any less "real"... as long as it
can do the same Celsius/watt as the real one. Look at
Carlo's hand drawn amps , they are "real".. in fact, I
copied him to do my boards.
BTW.. the one above only cost 0$ because I picked up
a truck load of DELL's for free.
HRII - what a sound!!
The first channel of my HRII is running sweetly - the second will be ready in the next hour or so.
For my first ever amp project this is absolutely fantastic (despite a few stumbles on the way - some of you know my power supply naiveties
). I designed my own PCBs and to get such a great end result is just wonderful.
I'm very glad I went as far as having 3 inputs and adding the volume pot - I could be spending hours listening to this!
To Carlos, and to everyone who helped him along the way with the HRII, a very big thank you for bringing this wonderful amp to us music fans.
I'll post pictures and videos as soon as possible - this amp is gorgeous. Even my girlfriend broke a smile hearing Sheryl Crow's vocals on 'On The Outside'.
Finally, of course, a very special thank you to 'Uncle Charlie' for this thread and his assistance during those final build stages.
The first channel of my HRII is running sweetly - the second will be ready in the next hour or so.
For my first ever amp project this is absolutely fantastic (despite a few stumbles on the way - some of you know my power supply naiveties
). I designed my own PCBs and to get such a great end result is just wonderful.I'm very glad I went as far as having 3 inputs and adding the volume pot - I could be spending hours listening to this!
To Carlos, and to everyone who helped him along the way with the HRII, a very big thank you for bringing this wonderful amp to us music fans.
I'll post pictures and videos as soon as possible - this amp is gorgeous. Even my girlfriend broke a smile hearing Sheryl Crow's vocals on 'On The Outside'.
Finally, of course, a very special thank you to 'Uncle Charlie' for this thread and his assistance during those final build stages.
Uncle Charlie is happy to listen that forever
I hope it will be good for you forever.
Womans are better than us to detect quality into audio...also children....i am happy your girl friend appreciated.
Now, let's dance!
Pictures?.... good...yesssss!
panzertoo@yahoo.com this adress is if you do not want to publish or do not have the software to crop...so... i am here to help...... G-L-A-D-L-Y
Carlos
I hope it will be good for you forever.
Womans are better than us to detect quality into audio...also children....i am happy your girl friend appreciated.
Now, let's dance!
Pictures?.... good...yesssss!
panzertoo@yahoo.com this adress is if you do not want to publish or do not have the software to crop...so... i am here to help...... G-L-A-D-L-Y
Carlos
Grrr, I'm office-bound today...
...but will be playing with the amp again this evening. I noticed yesterday that after playing for 15 minutes or so, the bass disappeared from the left channel - I think this is a sign of oscillation?
I have a 47p cap where it's recommended to start at 150p and go lower if you can whilst avoiding oscillation. Multimeter was showing 3mV of AC from output to ground.
Will replace the cap tomorrow if I can't get it steady tonight...
But still, that bass when it was there. It genuinely filled the room, solid, no flabbiness.
...but will be playing with the amp again this evening. I noticed yesterday that after playing for 15 minutes or so, the bass disappeared from the left channel - I think this is a sign of oscillation?
I have a 47p cap where it's recommended to start at 150p and go lower if you can whilst avoiding oscillation. Multimeter was showing 3mV of AC from output to ground.
Will replace the cap tomorrow if I can't get it steady tonight...
But still, that bass when it was there. It genuinely filled the room, solid, no flabbiness.
Forever13 said:...but will be playing with the amp again this evening. I noticed yesterday that after playing for 15 minutes or so, the bass disappeared from the left channel - I think this is a sign of oscillation?
I have a 47p cap where it's recommended to start at 150p and go lower if you can whilst avoiding oscillation. Multimeter was showing 3mV of AC from output to ground.
Will replace the cap tomorrow if I can't get it steady tonight...
But still, that bass when it was there. It genuinely filled the room, solid, no flabbiness.
...just to expand on the AC problem, it appeared once I'd fitted the amp boards into the case, having linked up the signal inputs and speaker outputs. It was fine when the boards were out of the case being tested.
I think I read on Rod Elliott's site that inputs and outputs too close together can sometimes cause AC to appear...maybe I need to explore some shielding too, if the change of capacitor doesn't work?
heheheh.... solder your boards once again
sometimes bad joint only....nothing so problematic as magical mistery multiple loops or unobtanium ciclic into the inter shield of the magnetic displacement into the paralaxis of intergalactic mess.
Be simple... first check solder..them go imagining super problems.
regards,
Carlos
sometimes bad joint only....nothing so problematic as magical mistery multiple loops or unobtanium ciclic into the inter shield of the magnetic displacement into the paralaxis of intergalactic mess.
Be simple... first check solder..them go imagining super problems.
regards,
Carlos
Hey Carlinhos
I'm enjoying my DX HR II on a daily basis.
Probably not good looking but great sounding:
http://picasaweb.google.com/lh/photo/mArjR8fyKGvsZPvdwey5zw
As you see, it is hard for me to finish my projects What begin as a test configuration stays as a definitive one, he, he...
Saludos fraternos,
Mauricio.
I'm enjoying my DX HR II on a daily basis.
Probably not good looking but great sounding:
http://picasaweb.google.com/lh/photo/mArjR8fyKGvsZPvdwey5zw
As you see, it is hard for me to finish my projects
What begin as a test configuration stays as a definitive one, he, he...Saludos fraternos,
Mauricio.
It is fine... a real DIY construction... a real man thing
We are amateurs... i know that people are so competitive they try to make better than factories.... i think this is waste of time.
Life is short, better to build 100 units and listen that produce a nice one to show to the girl friend, some friends or to forum folks.
I enjoy to go listening..others enjoy to show themselves.... nothing wrong to show ourselves...we need some Ego massage for sure..all of us...but only Ego massage and not really DIY activity?
Some guys spent 6 monthes bulding... i can build and listen 180 amplifiers during this time.... 6 monthes of fun to me...and 6 monthes of hard work to them...bad business.
Why to make better than factories?... factory will sell hundreds and will feed all factory group...all staff..and the one will feed only his pride.... a very big pride i think.
I feel good when i see a real DIY... someone that made as fast as he can to enjoy sonics and music.... your construction is a real man construction in my point of view.
Saludos mi hermano sudamericano
Carlos
We are amateurs... i know that people are so competitive they try to make better than factories.... i think this is waste of time.
Life is short, better to build 100 units and listen that produce a nice one to show to the girl friend, some friends or to forum folks.
I enjoy to go listening..others enjoy to show themselves.... nothing wrong to show ourselves...we need some Ego massage for sure..all of us...but only Ego massage and not really DIY activity?
Some guys spent 6 monthes bulding... i can build and listen 180 amplifiers during this time.... 6 monthes of fun to me...and 6 monthes of hard work to them...bad business.
Why to make better than factories?... factory will sell hundreds and will feed all factory group...all staff..and the one will feed only his pride.... a very big pride i think.
I feel good when i see a real DIY... someone that made as fast as he can to enjoy sonics and music.... your construction is a real man construction in my point of view.
Saludos mi hermano sudamericano
Carlos
AndrewT said:
Hi Andrew,
I'll need to recheck those measurements - I just did a straight AC test from output to ground.
The initial bass problem was a schoolboy error with the speaker jumpers, and there is plenty of bass now, but I will make those checks that you mention.
If it's anything to go by, at full volume, but no signal, there's a noticable sharp buzz (not too loud) coming through the speakers. I say buzz rather than a hum - it's not a 50-60Hz sound, if that makes sense?! I don't know what this might suggest?
Thanks ever so much for your post Andrew,
Darren
No more Optimus amplifier, testing high current into the HRII...
... i found that 1 ampere or higher standby bias does not give us any advantage into sound reproduction.... TESTED!
I found was sligthly mufled into higher bias....also i have found the optimized bias point is around 250 miliamperes (as Nordic said..he was rigth!).
Comparisons made, using two identical amplifiers, same parts and same supply, into a single speaker, gave me this result..instead to adjust your stand by bias to 60 to 100 miliamperes, it is better to increase it to 250 to 300 miliamperes because performance was better than lower bias and higher bias.
So.... Optimus is dead....now we have HRII Optimized!
Be happy folks.
Enjoy Dx Amplifier.... sounding near the perfection.
regards,
Carlos
....................................................................................................
A lot of Brazilian folks visit this forum to colect informations about my amplifiers..because of that this message in portuguese... say that is better to adjust to 300 miliamperes.
... i found that 1 ampere or higher standby bias does not give us any advantage into sound reproduction.... TESTED!
I found was sligthly mufled into higher bias....also i have found the optimized bias point is around 250 miliamperes (as Nordic said..he was rigth!).
Comparisons made, using two identical amplifiers, same parts and same supply, into a single speaker, gave me this result..instead to adjust your stand by bias to 60 to 100 miliamperes, it is better to increase it to 250 to 300 miliamperes because performance was better than lower bias and higher bias.
So.... Optimus is dead....now we have HRII Optimized!
Be happy folks.
Enjoy Dx Amplifier.... sounding near the perfection.
regards,
Carlos
....................................................................................................
A lot of Brazilian folks visit this forum to colect informations about my amplifiers..because of that this message in portuguese... say that is better to adjust to 300 miliamperes.
Attachments
330mA is very hot?
Hi Carlos,
I've taken my HRII boards back out of the case to restart testing (to try and fix that AC I found).
I also put a proper capacitor in place of those 47p disc I had (oops - the BOM said silvered mica and I missed it - now put 68p silvered mica caps in).
However, back on the topic of 330mA....this standby current makes my relatively small heatsinks pretty damn hot at idle. It's making me a bit uncomfortable about the amp!!
60mA idle hardly made a difference to the heatsinks. 150mA started to warm them up, but 330mA is hot stuff!
I think I'll have to stay around the 100mA mark?
Kind regards,
Darren
Hi Carlos,
I've taken my HRII boards back out of the case to restart testing (to try and fix that AC I found).
I also put a proper capacitor in place of those 47p disc I had (oops - the BOM said silvered mica and I missed it - now put 68p silvered mica caps in).
However, back on the topic of 330mA....this standby current makes my relatively small heatsinks pretty damn hot at idle. It's making me a bit uncomfortable about the amp!!
60mA idle hardly made a difference to the heatsinks. 150mA started to warm them up, but 330mA is hot stuff!
I think I'll have to stay around the 100mA mark?
Kind regards,
Darren
maxlorenz said:Hi Forever,
But how did it sound to you?
If you find it is a worthy improvement soundwise, then I would recommend considering bigger heatsinks
How hot? Burn fingers hot? Tº readings?
Regards,
M
Hey M,
I didn't get as far as listening to the amp at 330mA standby - the sinks weren't fingers burnt hot, you could keep your fingers on there, but it was uncomfortably hot. The sinks are rated at 3.7C/W each - not big at all. I'm afraid I don't have temperature readings on my meter.
The problem I've got is that I've used a case from an old valve line stage that is fairly tiny - I really can't get bigger heatsinks in there. (I mean, it's 320mm wide, 200mm deep, and just 60mm high). Pic attached.
Anyway, I've gone back to 60mA, and the amp does sounds great! It's been playing for 40 minutes or so and the sinks are practically cold. I'll edge the standby current up gradually once I'm sure the heat isn't too much.
Lesson learned - don't use a tiny case for your first amp project!!
Cheers for now,
Darren
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