My 2006 (?) HR Desktop Portable amp + DAC has a 4.5-6V input on the back for the 4-D battery brick. I'd like to use a rechargeable lead-calcium 6V battery and was considering putting a 3A diode in series with a fuse and positive lead of the battery to drop the open-circuit voltage of the fully charged battery to about 6V even (on-par with 4-D cells). However, it would be nice to not have to lose that bit of juice.
I recall reading over the past couple of years as I've been browsing your website that at one point HR used Cosel DC-DC converters. From all the specs I can see on the DC-DC converters (I even have one in a homemade amp I built) they operate 4.5V to 9V, so a 6V SLA secondary battery seems like it would be okay.
For reference, I purchased the HR Desktop Portable + DAC just before your 2007 release of the rechargeable version.
Should be no problem at all using the 6v SLA battery pack on the Portable Desktop unit -- I would not even worry much about the 3A diode so long as the power rating is not much above that 6v standard.
Please feel free to shoot Mike Olson HR Service Manager an e-mail (mikeo@headphone.com) if any lingering questions!
Powering pre-2007 HR Desktop Portable w/ SLA Battery?
Linear Mode
