This is a commercially built Objective2 amp with the agdr 'booster board' which enhances the performance of the amp, significantly increasing output current capability and reducing dc offset amongst other improvements.Booster board additional info:O2 Booster Board
There is a discussion thread about it on this site.
agdr tuned the gain to my requirements by creating the voltage divider at the inputs, resulting in 0.67x on Lo gain (good for my sensitive IEMs) and 3.4x on Hi gain (works fine with a 2V RMS DAC and my 250Ω Beyers). Gain can be tweaked to your needs (as agdr did for me) by changing 4 resistors and two caps. agdr installed sockets for the gain switch R's so they can be changed without soldering (the booster board does make them hard to get at, however.)
Included but not shown are the 12VAC wall wart; ~$40 worth of Mouser parts consisting of replacement and upgrade parts; soldering and building supplies (battery iron, flux remover, solder sucker, tools etc). I think my building days are over. There isn't much in the way of turnkey kits á la Dynaco/Heathkit and I don't have the motivation, tools, or skills to take on something like the Whammy which lacks switchable gain (something I find very useful) and also requires the builder to 'engineer' and (to an extent) fabricate the enclosure.
Shown but not included are the batteries agdr was using for his bench testing.
Asking $100 + actual shipping cost (The booster board alone was $129). Get the amp everyone loves to hate- only better. Paypal and Venmo accepted.
There is a discussion thread about it on this site.
agdr tuned the gain to my requirements by creating the voltage divider at the inputs, resulting in 0.67x on Lo gain (good for my sensitive IEMs) and 3.4x on Hi gain (works fine with a 2V RMS DAC and my 250Ω Beyers). Gain can be tweaked to your needs (as agdr did for me) by changing 4 resistors and two caps. agdr installed sockets for the gain switch R's so they can be changed without soldering (the booster board does make them hard to get at, however.)
Included but not shown are the 12VAC wall wart; ~$40 worth of Mouser parts consisting of replacement and upgrade parts; soldering and building supplies (battery iron, flux remover, solder sucker, tools etc). I think my building days are over. There isn't much in the way of turnkey kits á la Dynaco/Heathkit and I don't have the motivation, tools, or skills to take on something like the Whammy which lacks switchable gain (something I find very useful) and also requires the builder to 'engineer' and (to an extent) fabricate the enclosure.
Shown but not included are the batteries agdr was using for his bench testing.
Asking $100 + actual shipping cost (The booster board alone was $129). Get the amp everyone loves to hate- only better. Paypal and Venmo accepted.
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One week in and nothing but one tire kicker so guess Audiogon would be the next stop before the Bay.