Cheap Nice and Funky Amek 2500 preamps

[pvision]

We should acknowledge the debt owed to Graham Langley for the 2500 and other Amek consoles. Standard components + intelligent design = good-sounding consoles

 

[Ricardus]

Why don't you just design it ? Isn't it the whole point of DIY, instead of asking others to do it ?
Everything is already here : schematics, BOM and all... You just have to make it fit in a 500 PCB... it's that easy !!

Yeah. I know. Thanks.

I'm just registering surprise that no one has done it by now since they're well regarded preamps and it's such low hanging fruit.

 

[thomasdf]

Because it’s your time to shine

 

[sahib]

We should acknowledge the debt owed to Graham Langley for the 2500 and other Amek consoles. Standard components + intelligent design = good-sounding consoles

Our MICPRE ONE is actually based on 2500 topology. And designed by the very Mr Langley too.

I know this is DIY but sometimes you end up re-inventing the wheel.

If you do not need the instrument input and meter functions I can happily supply it as a cut down versions.

 

[Ricardus]

Our MICPRE ONE is actually based on 2500 topology. And designed by the very Mr Langley too.

I know this is DIY but sometimes you end up re-inventing the wheel.

If you do not need the instrument input and meter functions I can happily supply it as a cut down versions.

I'm personally just looking for the preamp with phantom. Phase and pad would be fine but not necessary.

I have a bunch of projects I'm working on now which is why I haven't attacked this as a 500 series module, but would happily contribute a panel design if someone did the PCB.

 

[sahib]

How about this?

Metering, instrument input and monitor output are omitted. Better to leave LOz as it gives you two input impedance options. HPF is certainly a good thing to have. Both done passively anyway, so negligible cost.

Would it do?

 

[Ricardus]

How about this?

Metering, instrument input and monitor output are omitted. Better to leave LOz as it gives you two input impedance options. HPF is certainly a good thing to have. Both done passively anyway, so negligible cost.

Would it do?

Sure. But I'm still not sure what you're offering?

 

[sahib]

Normally I have no problem of offering metalwork and blank PCB if this is what you want.

However, you will find it extremely difficult to source the illuminated switches. So, better to include them.

The rest are usual suspects,.

Gain switch is one pole 12 position Grayhill and the fader pot is 10kLOG.

Semiconductors are ;

1 x THAT 320
3 x BC560
2 x 5532
2 x OP275

 

[Ricardus]

Normally I have no problem of offering metalwork and blank PCB if this is what you want.

However, you will find it extremely difficult to source the illuminated switches. So, better to include them.

The rest are usual suspects,.

Gain switch is one pole 12 position Grayhill and the fader pot is 10kLOG.

Semiconductors are ;

1 x THAT 320
3 x BC560
2 x 5532
2 x OP275

Ah, that sounds very reasonable.

 

[sahib]

I can offer it in the following form.

1 x Main PCB
1 x Instrument input/Meter PCB
1 x Faceplate
1 x Backplate
1 x LHS Screen plate
1 x Red illuminated push button switch + clear cap
1 x Yellow illuminated push button switch + clear cap
1 x Green illuminated push button switch + clear cap
1 x Blue illuminated push button switch + clear cap
1 x 10kLOG Potentiometer + right angle fitting card
1 x 20 Way box header
1 x Ribbon cable assembly

I have also included the 20 way box header and ribbon cable assembly to connect the instrument/meter card to the main board as I already have a lot already made up. Saves you from the hassle of making it.

Rest of the (cut-down) BOM is attached. I have also attached low-res images of the PCBs.

If there is any interest I can start a support thread for this as a project..

I have a WM listing but I would like to keep this separate. So, please contact me by PM.

 

[zzzzz]

Still waiting for a nice 500 Series DIY implementation of this. I want to build at least 6.

Sahib has already posted the really awesome implementation of this right before me, but I'm just seeing this request now.

I had started a very simple 500 series version of this project based on the original schem from Gyraf's site plus the one in this thread using the THAT1646 (because I like that idea) and easy to find off-the-shelf components. Feeling inspired to finish it up, but I would probably just make boards and not a kit. Will probably also make a non-500 series version as well.

Booked solid with sessions for the next several weeks but perhaps will make moves in February.

 

[Ricardus]

Sahib has already posted the really awesome implementation of this right before me, but I'm just seeing this request now.

I had started a very simple 500 series version of this project based on the original schem from Gyraf's site plus the one in this thread using the THAT1646 (because I like that idea) and easy to find off-the-shelf components. Feeling inspired to finish it up, but I would probably just make boards and not a kit. Will probably also make a non-500 series version as well.

Booked solid with sessions for the next several weeks but perhaps will make moves in February.

Sounds cool.