Amek M2500 Build and Support Thread

kato

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One of the 4 channels is stuffed with components already.

Not trying to make this a sales post, but I'd hate to see them go to waste.

If anyone is interested, $10 for all 4 PCBs plus shipping.
I can leave the etch resist on, or remove it with acetone prior to shipping leaving clean copper.



 

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ipindalieson

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kato said:
Sorry to bump an ancient thread. Someone recently PM'ed asking for the original files. They had been deleted.

Here is a new link to the DIY version of the Amek 2500 by Olaf Matthes.

It will prompt you to create a dropbox account, but I believe you can bypass that request and download without creating an account.


Hi Matthew,  its me again :)

What the power current you reckon to drive this 2 pres?

Thank you

Ipin
 

kato

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ipindalieson said:
Thank you Matthew.  :)

Btw, with this design, is it ok to put the original TL072 ic's on the board?

Yes.
I could be wrong, but I don't think there are any significant changes from the original that would prevent a TL072 or TLE2072 from working fine, and probably sounding exactly the same as the more modern replacements.
 

ipindalieson

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kato said:
Yes.
I could be wrong, but I don't think there are any significant changes from the original that would prevent a TL072 or TLE2072 from working fine, and probably sounding exactly the same as the more modern replacements.

Thank you Matthew.

I've finished the soldering job for 2 boards, but haven't tested it yet, just want to make sure everything is alright  :)
All the ICs are TL072, hope its okay, and where is RG going? Potentiometer? (1kohm?) or Rotary gain switch?

Ipin
 

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Ricardus

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Looks good.

I've been interested in building some Amek preamps. Not sure which ones people like the best, and which ones have any PCBs available, but it is on my list.
 

kato

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ipindalieson said:
Thank you Matthew.

I've finished the soldering job for 2 boards, but haven't tested it yet, just want to make sure everything is alright  :)
All the ICs are TL072, hope its okay, and where is RG going? Potentiometer? (1kohm?) or Rotary gain switch?

Ipin

I used a 1k reverse log pot.
A rotary switch would probably work as well, similar to the green preamp.
 

ipindalieson

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Ricardus said:
Looks good.

I've been interested in building some Amek preamps. Not sure which ones people like the best, and which ones have any PCBs available, but it is on my list.

Thank you Ricardus, Haha, yer I made a pair of this version too  ;D  I'll compare them tomorrow,

Ipin
 

ipindalieson

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kato said:
I used a 1k reverse log pot.
A rotary switch would probably work as well, similar to the green preamp.

Thank you Matthew! You rock  8)
I'll try it tomorrow and let you know, can't wait to compare them with my Greens and the SSLs

Ipin
 

kato

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ipindalieson said:
Thank you Matthew! You rock  8)
I'll try it tomorrow and let you know, can't wait to compare them with my Greens and the SSLs

Ipin

Check out Pier Paolo's schematic in an earlier post.

He recommends a couple 220µF caps inline with the pot, which I think the Green preamp used as well.
 

ipindalieson

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Hi Guys,

After a long delay, finally I managed to do a proper test to the Pres, I put TL072s on the boards, and no sound, and I just realized, the pinout of the ICs is different. So I put OPA134 on it. It sounds great and it workes like a charm  ;D I'll post a picture when I finish racking them.

Thank you Matthew for the documents!!  ;D

Ipin
 

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