(just or not just, but) Another gainclone page

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Thanks all.

Digi01, I’ll send you, not a problem, just drop me an e-mail with your address, attachments are not feasible in diyAudio mails.

Philo, considering the dimensions of the heatsink it is not strange that it heats too much. Without the hood it is still quite acceptable though. Additional heatsinks saved from the old processor will go left and right at the current heatsink. Holes will be made at the bottom and the back of the case. Should be enough. Btw, that second amp which has whole 2mm aluminum case almost can not get even warm, no matter how long or how loud it works.

Pedja
 
Joe Rasmussen was right…

It is indeed important to have some kind of low pass filtering at the chip itself. Last night I tried it with my ‘clone’s JFET input buffer. I will update the content of my gainclone page with it this weekend. For now, this schematic shows what I have at this moment. I usually practice to take a step back to check what I really have made, and will do the same now also, but this sounds like I have got a missing point about that buffer. Filter rolls-off at 20kHz 0.09dB and phase shift is 10° (matches to the “magic” -3dB at 130kHz rule). These values are derived by simulation and are confirmed by measurement (everything happened last night). FET is hooked to 15V and sourced by some 14mA. I intend to exclude R1, just need some time to determine the FETs output impedance (simulator shows some 25Ohms, if so, then C1=47nF will respond to this).

Pedja
 

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Pedja said:
Joe Rasmussen was right…

It is indeed important to have some kind of low pass filtering at the chip itself. Last night I tried it with my ‘clone’s JFET input buffer. I will update the content of my gainclone page with it this weekend. For now, this schematic shows what I have at this moment. I usually practice to take a step back to check what I really have made, and will do the same now also, but this sounds like I have got a missing point about that buffer. Filter rolls-off at 20kHz 0.09dB and phase shift is 10° (matches to the “magic” -3dB at 130kHz rule). These values are derived by simulation and are confirmed by measurement (everything happened last night). FET is hooked to 15V and sourced by some 14mA. I intend to exclude R1, just need some time to determine the FETs output impedance (simulator shows some 25Ohms, if so, then C1=47nF will respond to this).

Pedja

Hi Pedja

Thanks for the link via email.

Keep us posted re the sonic effect and also vary the Lo-Pass by ear, no matter what the theory says. Let us compare the values I ended up with and yours. It will be facinating, awaiting your report.

Joe

PS: Like your choice using 170 fet (I use its very close cousin 369BL in a number of projects) and the CS as well. I approve.
 
Joe, it seems you were right again. I tried the lpf with the slope similar to that you proposed (I put to the schematic above R1=75 Ohms, C1=47nF; 1kOhm-4.7nF could be better since styrene cap can be used) and… fine, just fine. I did not like the idea of such radical (coming inside the audio band) roll-off, but it works.

Anyone else to join the experiment?

It is understood, the time was too short for the extensive listening. But I am quite sure I am close to something better than bare ‘clone. For some reason I still do not understand (though I have presumptions about it for the export), the buffer made some sort of the aggressive dirtiness for which I found is mostly coming out from my tweeter. Making this lpf and lowering its roll-off point makes that stress became less and less, but even more than that, soundstage and resolution improved. All the time dynamics and openness I get the first time I applied the buffer, is preserved. I have some further plans regarding the filtering.

I updated my gainclone page with this.

Pedja
 
Congrats to a VERY GOOD homepage Pedja

Congrats to a very good homepage,
Pedja.
Yes,
Some good things Can come out of Serbia

Not so big website.
But the stuff you've got
shows us all about
your great knowledge of some things in audio.

And your circuits, test results and simulations
are presented simply (without stirring up my mind)
and With Nice Style!

You do as Nelson does, keeps it simple ......

You know most that makes good hifi.
digital - solid - tubes - loudspeakers
And you also have some common sence
to understand that EF86 is a tube for hifi.

Very informative article of Power IC Amp - gainclone

I have gotten several interesting links from you, Pedja, these last 2 years.
Still I keep them safe in my PC.
You have got to make a more interesting link-page!
!!!! Please Share It With Us !!!!

StartPage & GainClone Article Page

http://www.geocities.com/react_71/audio/
http://www.geocities.com/react_71/audio/gainclone/gainclone.htm

- Non-OverSampling, DAConversion, CD-Mods, Pedja's System, MicroPhone Preamp -

http://www.geocities.com/react_71/audio/non_os/non_os.htm
http://www.geocities.com/react_71/audio/dac/dac.htm
http://www.geocities.com/react_71/audio/cd_mods/cd_mods.htm
http://www.geocities.com/react_71/audio/system/system.htm
http://www.geocities.com/react_71/audio/mic_preamp/mic_preamp.htm


;) halojoy (or gromanswe, as I was called at AudioAsylum.com, when we first met) ;)
 
Halo Groman

Thanks for all these kind words.

You won, nobody lost. ;) Glad to have you back. Be smart as you can.


halojoy said:
Some good things Can come out of Serbia

Hehe, this tone reminds me on the statement of the British ambassador in Belgrade a few weeks ago: “You in fact have two problems – problematic image and the fact you are not aware of it.” ;) (I couldn’t come across the original statement, this is my translation back to English.)

:cool: :cool: :cool:

halojoy said:
I have gotten several interesting links from you, Pedja, these last 2 years.
Still I keep them safe in my PC.
You have got to make a more interesting link-page!
!!!! Please Share It With Us !!!!

(Your quest got me started to think: is this possible, I actually don’t have my secret place on the net?)

So, considering both topics, yes, many good things are coming out of Serbia:

Dusko Gojkovic
Mitar Subotic aka Rex Ilusivii
Darkwood Dub

The question is however: who/what the world is looking for?

Pedja
 
Pedja

hi,

congrats, your new homepage is super....

i noticed that you tried some regulation for the lm3875....and yes its hard to find negativ Vregs wich can output more than a couple of amps....
so you use the positiv lm338 both as positiv and negativ Vreg, does it introduce any problems or performance degradation as used this way...?
i have some lt1083 Vregs, and i could be tempted to try it out - and they seem perfect for the job...?

:)
 
Official Court Jester
Joined 2003
Paid Member
Re: Halo Groman

Pedja said:
Thanks for all these kind words.

You won, nobody lost. ;) Glad to have you back. Be smart as you can.




Hehe, this tone reminds me on the statement of the British ambassador in Belgrade a few weeks ago: “You in fact have two problems – problematic image and the fact you are not aware of it.” ;) (I couldn’t come across the original statement, this is my translation back to English.)

:cool: :cool: :cool:



(Your quest got me started to think: is this possible, I actually don’t have my secret place on the net?)

So, considering both topics, yes, many good things are coming out of Serbia:

Dusko Gojkovic
Mitar Subotic aka Rex Ilusivii
Darkwood Dub

The question is however: who/what the world is looking for?

Pedja

I think that you are welcome at RAT :)
(in fact ,not just you :)
 
@ Choky:

If I only could have capabilities to participate in so many places and to deal extensively with so many things, I would probably come there… Thanks for the invitation, who knows, maybe one day… ;)

@ all:

Since the traffic at my site occasionally achieves allocated bandwidth thus being temporarily unavailable (happens rarely, but happens), Halojoy was kind enough to host the mirror site at his own server:
http://213.100.118.115:7000/
http://213.100.118.115:7000/react_71/audio/

Pedja
 
Pedja said:

Since the traffic at my site occasionally achieves allocated bandwidth
thus being temporarily unavailable (happens rarely, but happens),
Halojoy was kind enough to host the mirror site at his own server:

http://213.100.118.115:7000/
http://213.100.118.115:7000/react_71/audio/

Pedja
It is always a pleasure to help
God Guys.
Bad Guys already gets their help - from devil himself


ORIGINAL LINK
with the "Good Stuff"
(Album with Bluesman Eric Bibb at "Opus3 Records" )

http://www.geocities.com/react_71/


halojoy - back in town
his enemies, dislikers - are displeased :mad:

his friends, joylikers - jump for joy :cool: ;) :) :) ;) :cool:
 
A quick note of thanks (and advice) for those sharing their new pages with us via Geocities.

When your site is not available due to traffic, it is because you have exceeded the bandwidth allowable for the free sites and is temporarily shut down. They come back up after a pre-determined amount of time.

It is very important to know that your graphics are the horse-chokers in the bandwidth use. Several points to consider may help you keep your sites free AND more accessible with less downtime.

1) Keep the non-photo graphics (i.e. cool web slice designs for your page) to a minimum.

2) Keep the photos reasonably small. And compress the heck out of them. I am a professional photojournalist and use cell phones to transmit photos for publication (i.e. BIG) every day. Keep you pix small (say, 5"x72 dpi on the long deminsion.) When you jpeg them, try cranking them down to about a level "3" (out of 10, or 12) on the size/quality scale. You would be surprised at how decent some pix look and how much bandwidth you save. If you have an unsharp mask filter on your Photoshop (or the like) program, you can use it to compensate. An added bonus is that your pages, with more compressed photos, load faster for dial-up users.

3) Consider linking (with pop-up pages, so your page stays there) to off-site photo hosting for your pix. Yahoo gives you lotsa space for free. Best of both worlds.


Again, thanks for the effort. We all benefit. Except possibly my neighbors, when the GC is finished!

GND
 
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