Kronos147
09-11-2008, 03:07 AM
Hello all,
Things have been busy over at VSI. I have been hounding the techs to concentrate on a preamp we called first the M-1. Then John Hardy helped with a phone call to change the name. We went with MX-1 for a brief moment, and then we thought that was too trite.
The L-21 is going to be the designation.
It is built around a discrete amplifier block that VSI has been working with for years. When the developer of the block met up with another man who has a transformer company, there was an immediate synergy.
At one point a few of the engineers came over to the studio with 2 pairs of transformers mated to the blocks. We inserted each pair one by one to my then ITB system. I was BLOWN AWAY!
We tried both pairs and one had better articulation, detail, clarity, depth, and low end. I guess when I declared that I settled a bet. As they tried to leave I announced my studio fee for that night was the preferred pair and the power supply. A few months later a basic two space rack was carried in, with an on board power supply, and the blocks and transformers were mounted in the chassis. The 'magic bus' was born.
I pestered them about doing mic pres after that, and after a while the L-21 design was born. The nice thing about VSI and their manufacturing backgrounds meant that all the circuit cards cards and metalwork were all laid out in CAD and build with CAM. After a few revisions of the circuit cards and minor changes to the transformers I had a few working prototypes in my studio. I loved them! During the R & D phase though I would mention something and then I would lose the prototypes for a few days while they were revamped. It was like that every time a change was made. That forced me at one point to get the 512c's I have now!
Now, I love the 512c. I was so glad I brought mine to the 500 series shootout James at GS did. No one else had, and I think without the 'standard' to compare to that would have been a less successful day than it was. But now that I have the L-21's in the studio, I find myself turning to them more and more. I tracked guitars on my own song a few nights ago. I did half the tracks with the L-21 and half with the GTQ2 (for a significantly different flavor).
The L-21 uses an input transformer, discrete block, and output transformer, like the original 512 did. It has an output level potentiometer, not a shunt like the 512c. The L-21 had phantom and phase like the 512c, but the pad has two settings, -10 and -20. The pad is pre input transformer, so it avoids clipping the input tranny. It also has an insane high gain switch. I don't think I have used it but it may come into play with passive guitars using the D.I.. I have to try that again. I have been told it would be useful in a live application using the L-21 as a final stage line driver out of the console to the stage x-overs/amps.
The L-21 has a stepped attenuator potentiometer. Now this helps control the gain after the input transformer to avoid clipping the block. It switches silently, as do the pads. It also has a hi pass filter with two settings (or three, if you count off). The settings are a hard slope 40Hz, or a gentle slope 70Hz.
It took me a while to get used to all the features available in such a tight area. Now, I find them indispensable. I urged the designers to make a simple design, but as I went through the features I could live without, it wasn't that much different.
I thought the ability to see input and output to be a little redundant, but sometimes I drive the L-21 into a 550b and it is nice to see what I am sending it!
I have had my L-21's for about two weeks now. They are sonically the same as the M-1, but now sport a new color and a power on LED and a phantom LED. At first I was thinking 'does it really need that' but it is good to know all my L-21 are in the racks/lunchboxes correctly without having to power off/on to see each one's meter jump. It is good to be able to confirm from a distance that phantom has been turned off as well.
I hope this will serve as 'official notice' or a request at least to update the database!
Eric
http://www.vsiaudio.com/L21-02.JPG
Things have been busy over at VSI. I have been hounding the techs to concentrate on a preamp we called first the M-1. Then John Hardy helped with a phone call to change the name. We went with MX-1 for a brief moment, and then we thought that was too trite.
The L-21 is going to be the designation.
It is built around a discrete amplifier block that VSI has been working with for years. When the developer of the block met up with another man who has a transformer company, there was an immediate synergy.
At one point a few of the engineers came over to the studio with 2 pairs of transformers mated to the blocks. We inserted each pair one by one to my then ITB system. I was BLOWN AWAY!
We tried both pairs and one had better articulation, detail, clarity, depth, and low end. I guess when I declared that I settled a bet. As they tried to leave I announced my studio fee for that night was the preferred pair and the power supply. A few months later a basic two space rack was carried in, with an on board power supply, and the blocks and transformers were mounted in the chassis. The 'magic bus' was born.
I pestered them about doing mic pres after that, and after a while the L-21 design was born. The nice thing about VSI and their manufacturing backgrounds meant that all the circuit cards cards and metalwork were all laid out in CAD and build with CAM. After a few revisions of the circuit cards and minor changes to the transformers I had a few working prototypes in my studio. I loved them! During the R & D phase though I would mention something and then I would lose the prototypes for a few days while they were revamped. It was like that every time a change was made. That forced me at one point to get the 512c's I have now!
Now, I love the 512c. I was so glad I brought mine to the 500 series shootout James at GS did. No one else had, and I think without the 'standard' to compare to that would have been a less successful day than it was. But now that I have the L-21's in the studio, I find myself turning to them more and more. I tracked guitars on my own song a few nights ago. I did half the tracks with the L-21 and half with the GTQ2 (for a significantly different flavor).
The L-21 uses an input transformer, discrete block, and output transformer, like the original 512 did. It has an output level potentiometer, not a shunt like the 512c. The L-21 had phantom and phase like the 512c, but the pad has two settings, -10 and -20. The pad is pre input transformer, so it avoids clipping the input tranny. It also has an insane high gain switch. I don't think I have used it but it may come into play with passive guitars using the D.I.. I have to try that again. I have been told it would be useful in a live application using the L-21 as a final stage line driver out of the console to the stage x-overs/amps.
The L-21 has a stepped attenuator potentiometer. Now this helps control the gain after the input transformer to avoid clipping the block. It switches silently, as do the pads. It also has a hi pass filter with two settings (or three, if you count off). The settings are a hard slope 40Hz, or a gentle slope 70Hz.
It took me a while to get used to all the features available in such a tight area. Now, I find them indispensable. I urged the designers to make a simple design, but as I went through the features I could live without, it wasn't that much different.
I thought the ability to see input and output to be a little redundant, but sometimes I drive the L-21 into a 550b and it is nice to see what I am sending it!
I have had my L-21's for about two weeks now. They are sonically the same as the M-1, but now sport a new color and a power on LED and a phantom LED. At first I was thinking 'does it really need that' but it is good to know all my L-21 are in the racks/lunchboxes correctly without having to power off/on to see each one's meter jump. It is good to be able to confirm from a distance that phantom has been turned off as well.
I hope this will serve as 'official notice' or a request at least to update the database!
Eric
http://www.vsiaudio.com/L21-02.JPG