GDIY51X Headphone amplifier

[rob_gould]

Hi Carsten,

OT, but can you confirm that the holes at the top and bottom of the panel are in the correct position for mounting in a 500 / 51X rack?  Just wanted to double check before I copy them!

Thanks,

Rob

 

[culteousness1]

can you confirm that the holes at the top and bottom of the panel are in the correct position for mounting in a 500 / 51X rack?

Sure they are. I just did a test with my 51x rack and can confirm their fitting.
BTW, the panel is based on my SSL9K5/4K5 panel file, which I shared a dozen times without any complaints.

Carsten

 

[rob_gould]

Great  8)

Thanks for the confirmation!

 

[Janzoulou]

Sorry for bringing this up that late…  could anyone give me a hint where I can find the "Reichelt-BOM"? I think I missed somehow where it is?
Have there been any updates in between?

As it is looking like I´ll find time next week for finally stuffing the board. (crazy how long it is ago since I found time to do so…  :-\ )

Thanks!

 

[culteousness1]

I remember Udo provided this BOM. I am sure, he will chime in.

Any news on this lately, Volker?

Cheers,
Carsten

 

[kante1603]

I remember Udo provided this BOM. I am sure, he will chime in.

Any news on this lately, Volker?

Cheers,
Carsten

Hello,


yes,I still have that bom stored at Reichelt,here it is:


https://secure.reichelt.de/index.html?&ACTION=20&AWKID=771939&PROVID=2084

I'm not sure if it covers all options or changes,but it is the latest bom I stored there.
Should be around 98,586525847% o.k.,

best,

Udo.

 

[culteousness1]

And remember to include the parts for the "Carsten-Mod"  8)

2x 100kΩ, 2x 4.7kΩ and 2x 10 µF if my memory serves well...

 

[kante1603]

And remember to include the parts for the "Carsten-Mod"  8)

2x 100kΩ, 2x 4.7kΩ and 2x 10 µF if my memory serves well...

Yes.......man,that's too long ago,but now I remember having done it!
@Janzoulou:Together with the "Carsten Mod."- parts the bom should be a 100% now.


Thx Carsten!


Have fun,


Udo.

 

[Janzoulou]

Wheeew… so there is nothing that can come around the corner and bite me anymore!  8) Thanks a lot Udo + Carsten!! Cheers, Fredi

PS Will let you know how it went. Will do that little thing next week…. (hopefully!)

 

[culteousness1]

Any progress, Fredi?

 

[Janzoulou]

I found time to stuff the boards..

This HP - Amp will not go into a 51X-Rack but into my CRM.
Now I have to decide about the voltage I will drive the board with and which components to change on the PCB.
At the moment I am a little stuck about the impedances. My studio-partner has a HP with 36Ω and I read here about low Ω-HP there is some distortion on higher levels...?

There is a 2x18V toroid with plenty of power left in the housing I could use.

So at the moment I am concerned about the mods I should do on the board... Does anybody have some ideas?  I did quite a few projects but my knowledge about electronics is not at all pro...

 

[culteousness1]

I didn't notice any distortion on higher levels with my AKG K271 (55Ω), yet.
So, don't worry about loading too much  8) Others didn't report any problems too.

Would suggest to run the amp off ± 24 V as the original circuit.

Cheers,
Carsten

 

[Janzoulou]

This sounds good to me... So where did that issue come from ? Wasn't it a Sennheiser with 75Ω where someone mentioned some issues?

I am talking about the AKG K812-pro...

 

[[silent:arts]]

One note about powering:
the PCB needs +/-16V for the ICs,
plus the "high voltage" section for the Amp.
+/-24V only won't work.

 

[Janzoulou]

One note about powering:
the PCB needs +/-16V for the ICs,
plus the "high voltage" section for the Amp.
+/-24V only won't work.

Yes, I remember. I got +/- 15V at the moment in the housing... So this will not be a problem to change, and i guess the buffer amp won't get into any problems, receiving 16V instead of 15. 
So I give it a try with "original" (24 & 16 voltages and let you know how it came out... Thanks for your help!!!  :-[