Mini My Ref Rev C

[Bigun]

looking good - be careful you don't end up like me, with 5 amps not quite finished !

 

[Deleted member 148505]

looking good - be careful you don't end up like me, with 5 amps not quite finished !

After a year.. finished soldering all the components.. Now I have 4 amps not yet finished , Hopefully i'll finish this on July 2016

 

[Deleted member 148505]

Finally wired up after a year in my cabinet. Got no problems encountered, initial power up is good.

Sound is good, which inspired me to create a module without built in power supply, for connecting with SMPS etc..

Supply for LM318 is RC + shunt, can be connected to external supply through optional header.

 

[olaru]

Are you going to sell these on eBay?

 

[Deleted member 148505]

Are you going to sell these on eBay?

Will test thd first, size is 5" x 2.1"
main section is only 2" x 1.2"
pcb design not yet finalized

 

[Deleted member 148505]

Free layout update

Size 3.8 x 2.3 inches
only 1 jumper

feel free to suggest improvements on pcb design

 

[Deleted member 148505]

Slight update on pcb tracks

all poly caps = 5mm lead spacing
c3, c4, c5, c10, c11 = 8mm diameter
c7 - 10.5mm diameter
c15, c17 = 13mm diameter
jumper 2.5mm lead spacing
input terminal 5mm lead spacing
R20 = 7W TWM or SQM vertical resistor, or TO-220 2pin resistor

 

[Mark Whitney]

Try to connect R1, R2 and R4 closer together. Shorten the traces R2 and R14 to the speaker outputs. Speaker return is missing. Keep the loops as small as possible.

 

[Deleted member 148505]

Try to connect R1, R2 and R4 closer together. Shorten the traces R2 and R14 to the speaker outputs. Speaker return is missing. Keep the loops as small as possible.

Thank you for your suggestion, the board is limited only to 1 layer and 3.8 x 2.3 inches so there will be compromises.

In my previous layout, speaker return is intended to be connected to the power supply star ground and +speaker should be connected to external speaker protect module.

Here is the updated layout.

 

[Mark Whitney]

See if this helps:

Rotate and move up/left C12, R14 and R15 so that they are next to R17. This should give you some room to move C7 down/left.

Making a PCB layout is the most frustrating thing ever. I am never really happy with what I design.

 

[Deleted member 148505]

See if this helps:

Rotate and move up/left C12, R14 and R15 so that they are next to R17. This should give you some room to move C7 down/left.

Making a PCB layout is the most frustrating thing ever. I am never really happy with what I design.

Yep balancing benefits and trade-offs
How about this.

 

[Deleted member 148505]

no more suggestions, i guess it's nearly perfect.
uploading final layout.

 

[Deleted member 148505]

some 3d rendering..

 

[Spuds]

Will you be making boards available?

 

[manudrz]

I'm not a layout's specialist, but shouldn't it be better to let free space between AC in and Speaker out.

 

[Deleted member 148505]

This one needs DC supply since it doesn't have onboard rectifiers.
Attached update.

 

[Deleted member 148505]

My Ref on toroidal +/-35V DC supply.

 

[dagfaune]

I know that the schematic is not subject in this thread ...
But ... someone who knows how much R4 (390R) can be increased without compromising the sound, thus reducing amplification?

 

[miklos]

My Ref on toroidal +/-35V DC supply.

This amplifier is not the same as in #76

 

[Deleted member 148505]

This amplifier is not the same as in #76

Yes, that's my commercial version which is double sided and includes speaker protection circuit.