Bonsai’s X-Altra MC/MM Phono Preamp

[gtose]

I will post up on my website in an hour or so the BOM off the PCB which will clarify these few discrepancies.

Awesome! Thanks for the update. I’ll check it out and let you know if I run into any issues.

Greg

 

[dubbio]

Thanks for prompt reply. I like the idea of transimpedance plus DC coupled design and at the same time less complex topology as possible.

 

[sonidos]

Congrats, Andrew! I'm subscribed to the thread and will place an order very soon. This may well be the last phono pre I own.

 

[Bonsai]

Thanks Javier. I owe you a reply on the HP amp. Just been busy the last few days.

 

[sonidos]

Can't imagine what could be keeping you busy. No worries, take your time. I'm not going anywhere.

 

[audiorasp]

capacitor footprint

Andrew,
Would you mind explaining how to interpret some of the capacitor footprints, such as RB.14/.32 ? I'm not familiar with this description.

Thanks,
George

 

[Bonsai]

George, You shouldn’t have to worry about that since the BOM with the Mouser and RS part numbers (per the supplemental data published on the audioXPress website) calls up the right size part (same on all my PCB layouts BTW)

RB.14/.32 or say RB.5/.3 as examples: -

The bigger number is the diameter in inches, the smaller number is the lead spacing

 

[audiorasp]

OK, thanks. I was using a bom downloaded from your web page that doesn't have part numbers.

 

[Bonsai]

Yes, that’s just for reference and it’s ‘back generated’ from the PCB.

 

[Bonsai]

I have boards back in stock. Please see the X-Altra link below in my signature.

 

[sonidos]

Boards on order. Next step, scour my parts bins to see what I already have as my wife will give me her quizzical eye if she sees another large box of parts coming in through the door.

 

[Bonsai]

Haha. I have the same problem. I get ‘Another Mouser package?’

 

[Terps]

LSK389

Hi Bonsai. I received the boards and they are very nice quality. I have just started buying parts and wondered where you sourced the LSK389 FETs from?

 

[Bonsai]

Hello Terps

In tne UK I got mine from the local supplier (listed on the Linear Integrated Systems website) and Jan Didden sold me some as well.

My suggestion to all builders is you just email Linear Systems - in many cases you can buy them directly off their website.

Note that the PCB will accept either the plastic 8 pin SOIC or the 6 leg metal can version.

 

[Bonsai]

Here’s the link to the Linear Integrated Systems purchase page

Linear Systems

You can also get the LSK389B from local distributors detailed here

Linear Systems

 

[Terps]

LSK389

Thanks Bonsai. There are couple of places in the states who can supply of the shelf but carriage is expensive. So I have contacted Linear and Micross is the main UK distributor. Which grade is most suitable A,B,C,D to buy ?

 

[Bonsai]

I used B grade in both my builds and that’s what I recommend.

I got some devices from Micross - service was good and they arrived in a few days.

 

[sonidos]

Board and panel arrived in my mail in mint condition. A 1000 times better than the photos. I couldn't put it down last night. Ahh, just like Christmas morning.

 

[sonidos]

Has anyone ordered directly from LIS on this side of the pond? DigiKey has a min of 5 for $7 and change each. I don't need that many so I'll decide which route to go depending on price and stock from LIS. I may end up with extras that I would be willing to ship to someone in need for this project.

 

[Bonsai]

Board and panel arrived in my mail in mint condition. A 1000 times better than the photos. I couldn't put it down last night. Ahh, just like Christmas morning.