Group buy for SOHA pcb by digi01

[Qsilver 0]

Here is just a little update on the ongoing SOHA status ....

 

spec modification below:

1,volume,combo footprint for alps 27 and standard pot

2,the footprint of output jack is remove for easy front panel process

3,test points added

4,flexile caps footprint,lead space 5/7.5mm,18mm diameter

5,coupling caps,lead space 5/7.5/15mm

6,VR1,VR2 reseted for to92/to220 packaged regulator

6,LM337 move away from the caps for hot release

7,final PCB size is 100mm x 119mm

8,parts number updated

9,added 2 holes for stack classA buffer

 

P.S.

the pcb is double layer design,so I can use breakaway grounding concept.the power ground and signal ground is 'separate' without loops.there are big ground plate at the top layer for signal ground shielding.the ground plate was set up with gridding for physical stabilization.

 

It is almost at its final stage, but may have some changes for more improvements. Will try to keep you guys updated.

Rgds, Qsilver

[Tetsusaiga 0]

I'll go for the assembled option.. thanks..

[whiskeyjack 0]

Since already paid for my assembled diamond buffers, option 2 please.

[chins 0]

I'll take the assembled buffers. Thanks.

[Kube 0]

Is it too late to join the group buy then? I've been pretty busy, so I wasn't sure I had the time to finish the project...

[mb3k 0]

I'm hoping this will come soon, eagerly waiting for 2 months now, but I respect the design process so I can wait.

I was checking out tubes and the T-12AU7-G-EI-EL from http://www.tubesandmore.com/ looks promising and I think this will be appropriate for the SOHA. Anybody have recommendations for other tubes?

[Edwin 0]

Sorry for the lack of update guys...

 

Been busy with school, just got my exams over with last Friday. Here is the consolidation of the decision from those in the GB. Please do let me know if there is any mistake that I may make cos been looking at text for the past week, so vision still kind of blurry...

 

1)Edwin - 2 SOHA PCB w/ diamond buffer PCB

2)Qsilver - 2 SOHA PCB w/ diamond buffer PCB *paid* Option 1

3)heady - 1 SOHA PCB w/ assembled diamond buffer PCB *paid* Option 1

4)Kippei - 1 SOHA PCB w/ diamond buffer PCB *paid* Option 3

5)[Top-Gun] - 1 SOHA PCB w/ diamond buffer PCB *paid* Option 3

6)chins - 2 SOHA PCB w/ diamond buffer PCB *paid* Option 3

7)ridz- 1 SOHA PCB w/ assembled diamond buffer PCB *paid* Option 2

8)mb3k - 1 SOHA PCB w/ diamond buffer PCB *paid* Option 3

9)rko - 1 SOHA PCB w/ assembled diamond buffer PCB *paid* Option 2

10)Tetsusaiga - 1 SOHA PCB w/ diamond buffer PCB *paid* Option 3

11)haxyer - 1 SOHA PCB w/ diamond buffer PCB *paid* Option 3

12)whiskeyjack - 1 SOHA PCB w/ assembled diamond buffer PCB *paid* Option 2

 

Anyway, I will pass the info to digi01 to see how is the order like, whether can he fulfill the quantity that we wanted.

 

Also, the last thing that I had heard from digi01, before I retreated for my revision, was that the design for the boards have been finalized. He is in the stage of putting the prototypes thru some testing. Should be able to deliver by the end of this month.

Edited June 20, 2006 by Edwin

[Qsilver 0]

1stly, hope you did well in ur exams.

It's not a problem as testing the protos is done by the SOHA team (thot I have not check the other site if the team have receive those boards yet due to "world cup") hehe.

Please let us know when you gonna collect the $$$.

 

Thanks.

[rko 0]

i'll take option 2.

[thedoctor 0]

I'm hoping this will come soon, eagerly waiting for 2 months now, but I respect the design process so I can wait.

I was checking out tubes and the T-12AU7-G-EI-EL from http://www.tubesandmore.com/ looks promising and I think this will be appropriate for the SOHA. Anybody have recommendations for other tubes?

the NOS Mullard 12AU7 are somewhat raved as being the best. yet i've never tried them out.

i'm in favor of the Ei Elite gold pin 12AU7, though some class them as being bright. the JJ ECC82 sounds somewhat harsh to me, and the Electro-Harmonix as being too laid back.

 

the SOHA is somewhat sensitive to the tube used. which is a good thing in the sense that one could try all sorts of different tubes to match their preference. even more sensitive to tube rolling compared to the Millet Hybrid/YAHA/MHHA.

 

and so that everyone knows, i've tried the Diamond Buffer build a long time ago for the SOHA.

and with about 5% unmatch (if my memory recalls correctly) between the NPN and PNP pairs, the amp outputs 6V of DC offset.

and from experience working with Diamond Buffers, finding matching NPN and PNP pairs could be somewhat a pain.

[Tetsusaiga 0]

So, what's the latest news on the group buy??

[Qsilver 0]

The SOHA teams have recieved the valuation boards from Digi & started their solder.

Now waiting for the test results. As till now mains_hum have finished with his, still waiting for the rest of the team to complete & they will post the results. (Good & Bad)

Thats what I know of till now.

Edited June 26, 2006 by Qsilver

[neutralzz 0]

still hum? how abt dropping in a hum-pot for the heater?

[Qsilver 0]

still hum? how abt dropping in a hum-pot for the heater?

 

No hum, "mains_hum" is a username. My bad

[Edwin 0]

Good news guys, the ETA for our boards, according to digi01, will be the 15th of July. Would like to apologise for the delay as he wanted to make the design as perfect as possible.

 

In the mean time, can those in the Group Buy who are topping up for the extra boards and diamond buffers, please make a fund transfer of the remaining payment to my bank account? Please let me know when you have made the payment.