(Trace Audio Reference FAQ's)
Q: WHAT IS THE DIFFERENCE BETWEEN ALL THE CAPI PREAMPS?
A:
VP312- The VP312 is a faithful recreation of the oringal API 312 preamp module. It has a large 2503 outputs transformer and a 2622 style input transformer with a single 2520 footprint op amp. Sonically the VP312 has punchy mids and a smooth low end.
VP25- Thế VP25 preamp is essentially an exact recreation of the legendary preamp circuit found in the vintage APi consoles of the mid to late 70's. The 528/536 input modules have precisely this same exact circuit. The only exception being the change to the larger 2503 output transformer. Sonically this preamp has a nice extended low end compared to a VP312.
VP26- The VP26 is the exact same circuit as a VP25 EXCEPT it uses a smaller 2623 output transformer that gives it a little bit more focus in the upper mids.
VP28- The preamp section of the VP28 is almost identical to a VP26. One big difference is the VP28 features a second stage booster fader that actively boosts or attenuates the output. The great part about this second stage is it allows you to use low gain and high output for a clean signal or high input gain and low output for a more pushed aggressive sound.
VP28 PLATINUM- The mic audio path is very similar to the VP28. The main changes are Platinum exclusive CA2618 1:8 input transformers and Platinum exclusive CA2623-Pt Litz wire output transformers. In addition, Scott Liebers has created a ground up exclusive Platinum Super Dot opamp. Scott has referred to the Super Dot as his best sounding opamp yet! A FET Direct Inject has been added to the front panel of all Platinum preamps. The front panel jack is auto switching so inserting a 1/4" plug automatically activates DI mode. Like its kit counterpart, the VP28-Pt is a true 2-stage mic/line amplifier. The 2nd stage fader booster has 12dB of gain 'in hand', exactly like a real console. This allows for many different gain combinations. You can crank the fader and reduce the preamp gain or in contrast, attenuate the 2nd stage and crank the preamp gain for some sweet, additional harmonic content.
HEIDER FD312 H2- The preamp stage has been carefully modeled after the preamps in the famous Wally Heider Recording Studio 4 console custom built by Frank DeMedio circa 1972. The CA-0887 input transformer has a buttery smooth sound quality to it. To enhance this special preamp circuit even further, CAPI chose to employ a stepped fader similar to the popular VP28 preamp. In remaining true to the Heider@ circuit, all AC coupling capacitors have been removed from the audio path. This fader booster stage has 12dB of gain 'in hand', exactly like a real console.
Q: WHAT IS THE DIFFERENCE BETWEEN OP AMPS?
A:
CA-0252 (KIT)- Jeff Steiger of CAPI set out to create an op amp that is as faithful to the early 1970's 2520 API op amps. Jeff was gifted an un-potted 2520 from a close friend who got it from a trade show in the 1970's. Jeff was able to source a large inventory of parts that make this op amp sound just like those classic 2520s. These op amps are perfect for users that are looking for vintage grit with the all familiar mid forward punch.
CA-0252 (0EM)- The CA-0252 (OEM) op amp is nearly identical to the CA-0252 kit with the exception of a few transistors. Aside from being potted, the OEM version uses custom made BC414Cs for the input transistors and new-old-stock Texas Instruments TIS97 for the interstage NPN transistors. While sonically they are extremely close to the CA-0252 kit, the upgraded transistors make these op amps sound as close as humanly possible to the original 1970s 2520 op amps.
SL2520 RED DOT- Scott Liebers designed the SL-2520 as replacement op amps for vintage console restorations. The "red dot" is built to match the Huntington and Melville NY op amps from the 70's. It can be identified by the red dot found on the bottom of the op amp. The SL-2520's utilize the same circuit as the highly desirable vintage op amps from the 70's but with modern components. (The original transistors are no longer manufactured) Modern transistors are generally quieter and faster than their vintage counterparts. Through exhaustive lab and listening tests, Scott was able to match the distortion characteristics of the vintage op amps. These op amps deliver a punchy mid forward sound with a little bit more of a modern top and bottom end. These op amps are great for users that want a good blend of vintage and modern tone.
GAR2520- The gar 2520 was designed by Gary Barnett of Barnett Industries. Gary has built upon the reverse engineering work of Peter Lazaro, better know as "Peter Purpose". The gar 2520 is a nine transistor amplifier modeled after the legendary, mid '70's, Studio Systems/Huntington era 2520. Sonically the gar2520 accomplishes the vintage 2520 thing while using modern components. When pushed they tend to get a little bit more aggressive harmonically than- a CA-0252.
GAR17314- The gar 1731 was designed by Gary Barnett of Barnett Industries. This DOA is an eight transistor amplifier modeled after the legendary 1960's 1731. For those who do not know it, many of the engineers responsible for the 1731 joined forces with Saul Walker when he started APÍ. The starting point for the famous API 2520 was indeed the 1731. Overall, it's very similar to the sound of a 2520. The gar 1731 has a slightly smoother bottom and top; while simultaneously retaining the ever familiar aggressive, forward midrange we love about the 2520.