Starving Student II Headphone Amplifier

Those units are incorect. 111 dBV is something like 350kV, and 1uBar is ~73dBSPL. Perhaps it should be 111 dBSPL/V.
Pete

Yes, from another manual 111 dB/V is mentioned:
Specifications; Reboot - Bowers & Wilkins P7 Wireless User Manual [Page 6]

I think the other wrong specification was from B&W official homepage.
Thank you very much for the extra sets of tubes you provided. I made a quick test yesterday and the General Electric 18FX6 are almost silent. And they also sounds very very good. When I come close with my hands to these tubes they a less sensitive to pickup noise/hum. The RCA tubes picks up hum so with them I would need an extra shield. It is probably because I have no "earth ground" and maybe also because the headphones are very sensitive. 9-10 o'clock at volumen is loud. But with all tubes I can make it completely silent by shielding the tubes with my hands (if my hands has connection to chassis top). General Electric are nice tubes. When I get some shielding around the tubes I will listen more carefully to each set of tubes. I have also a couple of other brands on the way from ebay……..
 
Switches things on and off again
Joined 2000
Paid Member
For those of us who haven't started construction yet on our 'first batch' kits, could we purchase one of the 'second batch' PC boards?

Sure, that's a fine idea. We're happy to offer the updated PCB at cost to anyone from the first batch. Please note there are no changes at all other than larger solder pads. Please give me a day or two to organize the mechanics of it and I'll send an email out with the details.
 
Hi, today I placed my order for an SSII as part of the second batch.

When I ordered my ACA, I ordered two - in case the first build ended in disaster! It did not! Now I have two ACA's with rca or XLR balanced option!

My silly question relates to the feasibility of buying two SSII kits and connecting them in a single case for use with ACA's accepting a balanced input.
 
An email has just gone out to batch 1 purchasers with a link to let them obtain a batch 2 PCB at cost. If you didn't get the email, please check your promo/spam folders first, then contact the helpdesk. Thanks for the suggestion!

Jason
I tried to order my board today but when I went to check out the payment block appears to be broken, will not allow me to input card info. Is there a problem with the store?
 
Can you use other colors than blue for the LEDs that illuminate the tubes?

If you use the CCS plate load option (as opposed to the resistor load) you shouldn't change the LED. Not for a different color, or even a different brand/type of blue LED. The forward voltage of the LED sets the reference for the CCS, so changing it will change the plate current. Even within blue LEDs, the forward voltage varies from under 3V to over 4V.

If you use only the resistive load you can do whatever. And of course you can mount the LEDs inside the chassis so they don't show.

Pete
 
Of the different tubes I have tried the General Electric 18FX6 (made in USA) works best for me. These tubes are the less sensitive for picking up hum from the environment. They also sounds great. I have other brands on the way from ebay to try out. Maybe 18FX6 will be hard to find as NOS......as more and more build this amp....and want to try other tubes and have some spare for the years to come :)