Hi!
I have just finished cobbling together a pair of Expat Audio's Eden preamps. Expat is run by Rochey and Keith (SSLtech) from this forum, and with their experience and expertise I have high hopes.
The preamps are based on a INA163 chip, and come part-built with surface mount things, so most of the work is already done. All I had to do was wire up XLR ins and outs, a 5K gain control, and a ±15V power supply.
The boards were much smaller than I had expected, so the rack i ordered from Farnell is far to big! One could easily fit four or even eight of these in a 1U unit. I've ordered a shorter case for this and will do a transplant when it arrives. For now all the leads are left long until I know where everything will sit in its final home.
You can use a 5K pot for the gain, but I had a pair of nice Elma rotary switches, so made up some attenuators to give roughly 2 to 3 dB steps up to +54 dB from the INA163 preamp chip. It is a bit fiddly but a bit of tape helps keep the resistors in place whilst you solder. You can do this with Lorlin switches too.
The PSU board also came from Expat and has a regulated bipolar supply, and also a 48V output. I've built this for ribbon mics so I don't need that option. That also allows me to skip putting capacitors at the input. Overall it is a very simple build indeed.
So, how does it sound?
Well, so far I am VERY impressed. It has oodles of clean gain - in fact +60dB in total.. I did a couple of quick tests with some ribbon mics and their is no audible hum or hiss even at full gain. The sound is rather neutral and uncoloured in character - I'll try to post a frequency sweep next week but I expect it to be flat. It is a good option for ribbons where clean quiet gain is essential. It will certainly get used in our studio.
Rochey and Keith have done a really good job on this. Thanks guys! Here's their website...
http://expataudio.myshopify.com
I have just finished cobbling together a pair of Expat Audio's Eden preamps. Expat is run by Rochey and Keith (SSLtech) from this forum, and with their experience and expertise I have high hopes.
The preamps are based on a INA163 chip, and come part-built with surface mount things, so most of the work is already done. All I had to do was wire up XLR ins and outs, a 5K gain control, and a ±15V power supply.
The boards were much smaller than I had expected, so the rack i ordered from Farnell is far to big! One could easily fit four or even eight of these in a 1U unit. I've ordered a shorter case for this and will do a transplant when it arrives. For now all the leads are left long until I know where everything will sit in its final home.
You can use a 5K pot for the gain, but I had a pair of nice Elma rotary switches, so made up some attenuators to give roughly 2 to 3 dB steps up to +54 dB from the INA163 preamp chip. It is a bit fiddly but a bit of tape helps keep the resistors in place whilst you solder. You can do this with Lorlin switches too.
The PSU board also came from Expat and has a regulated bipolar supply, and also a 48V output. I've built this for ribbon mics so I don't need that option. That also allows me to skip putting capacitors at the input. Overall it is a very simple build indeed.
So, how does it sound?
Well, so far I am VERY impressed. It has oodles of clean gain - in fact +60dB in total.. I did a couple of quick tests with some ribbon mics and their is no audible hum or hiss even at full gain. The sound is rather neutral and uncoloured in character - I'll try to post a frequency sweep next week but I expect it to be flat. It is a good option for ribbons where clean quiet gain is essential. It will certainly get used in our studio.
Rochey and Keith have done a really good job on this. Thanks guys! Here's their website...
http://expataudio.myshopify.com