Looking for preamp recommendations to go with First Watt J2 - Under $1K on used market
First Watt specifies the input impedance at 100k ohms, but does not give a sensitivity number.The manual for the J2 indicates a sensitivity of 1.4 volts for full power, and a gain of 20 db. 20 db of power amp gain is relatively low. For example many of the Pass Labs amps are spec'd at 26 db, and many others from other manufacturers are higher. Best regards, -- Al |
Another possibility is a different form of passive that employs a transformer volume control. Instead of attenuating by burning off the signal in a resistor, transformer volume controls (TVC) attenuate by converting voltage to current. At lower volume levels (lower voltage and higher current), the sound seems to have more drive and vibrancy (passives tend to sound just a bit dull dynamically). To me, most TVCs are not very practical because they are stepped attenuators with too large a volume change between steps, and most are not remotely controllable. But, there are a few exceptions. MyEmia sells TVCs made by Dave Slagle that employ autoformers. While not cheap, these offer 1 db steps and are remotely controllable. Also, they offer 7 db of gain (again converting current to volume), which might be enough gain to cure your problem. I would contact Dave Slagle at MyEmia or at his own site Intactaudio.com (a supplier to the DIY crowd). He probably can offer ideas even if his stuff might not be your solution. |
Build the tubes4hifi SP14 kit at under $1000 and get something to compete with those $7000 tube wonders. Totally killer. http://tubes4hifi.com/pre11.htm#SP14 For a modest amount more, they'll build it for you. |
