An Updated IVP Preamp! With a Really Loud Dinosaur!

One of the most complex builds I've done in the past is the AionFX Intersound IVP pre-amp. I finished one up almost two years ago. It was a beast of a build. I was happy with the build itself, but the enclosure I used was both fairly unimaginative and had a minor error in the UV printing. I had recently gotten a request for an IVP build, so I decided to go all out this time and come up with something really amazing.

As I mentioned in my previous build, the IVP is one of the few builds that gets a full 5/5 difficulty rating on the AionFX scale. There are a lot of components, and while it can be tedious in parts, I've found builds where I have match and/or bias transistors to be a bit more difficult in many ways. That being said, I pretty much followed the exact same pattern I used last time. All of the resistors are new 1% metal film. There is a mix of new film and MLCC capacitors. All of the electrolytic capacitors are new Nichicon, and there are a total of seven integrated circuits - all socketed. There are also a few inductors and other unique bits in the power portion of the build as the circuit uses a +/-15V power supply.

For this particular build, I tried to get all of the hook-up wiring either under or around the edges of the enclosure. I had trouble getting the 9VDC input line underneath the board, so I decided to just run it across the top. I did that on my previous build and it hasn't caused any issues. The rest of the ground lines and audio input / output lines run around the edges of the enclosure. The jack connections are all insulated with heat shrink tubing as well. 

For the enclosure I decided to come up with something new, fun, and (of course) dinosaur related! According to Wikipedia:

"Parasaurolophus was a hadrosaurid, part of a diverse family of large Late Cretaceous ornithopods that are known for their range of bizarre head adornments, which were likely used for communication and increased hearing. This genus is known for its large, elaborate cranial crest, which forms a long curved tube projecting upwards and back from the skull in its largest form. Charonosaurus from China, which may have been its closest relative, had a similar skull and a potentially similar crest. Visual recognition of both species and sex, acoustic resonance, and thermoregulation have been proposed as functional explanations for the crest. It is one of the rarer hadrosaurids, known from only a handful of good specimens."

The Parasaurolophus is also believed to have been the loudest dinosaur, and there are some really good simulations of their call on YouTube. 

 

The clean preamp channel of the IVP is amazing. The Tube drive has a neat sound, but I'm not sure it really invokes a tube amp as much as I'd like. Dialing it in can also be a bit of a challenge as there are four different stages where the gain can be adjusted on the preamp, and if you go too far on all of them, you can get straight into squeal territory. Fortunately the AionFX documentation has a really good instructions on setting the EQ in a range that makes sense and lets you really adjust the EQ and gain without going into clipping (unless that's what you're after).