Non-pedal build: Ferrite DI

[lincolnic]

Here's the second half of my diyrecordingequipment.com purchase - the Ferrite DI. So named for the custom Cinemag transformer that powers this guy. If you don't know of them, Cinemag is a company that's been making audio transformers for decades, and they're a big part of the sound of some classic gear (API, Universal Audio, etc).

Like the Line2Amp reamp I posted a few days ago, this is an extremely simple build. You've got two 1/4" jacks, an XLR output, a ground lift switch, and the transformer. The build involves you wiring the transformer leads to their appropriate lugs, and that's pretty much it. The transformer itself mounts on the outside of the enclosure, which I wouldn't necessarily choose to do if I was designing this kit, but it seems sturdy enough. (The enclosure itself comes with a pretty rad silkscreened design.)

So what does it sound like? I'll be making some sample recordings when I get a little free time at work, but until then, I'd say it sounds pretty much like I expected: a round, solid low end, with slightly softened transients. In short, it sounds transformer-y. If you've ever used a good passive DI, you'll probably know what to expect.

You'll notice two ring terminals in the gutshot - these provide the ground connection for both the enclosure, and the transformer. They get attached to a screw in the enclosure's lid, so they've got to be unscrewed to see the guts. Forgive the crappy photos, I'm not good at taking them.



Note: I mounted the XLR panel upside down here, otherwise it would've been impossible to solder its connections.





Again, another dead simple, useful, and great-sounding project. For anyone interested, you can find the kits here: http://www.diyrecordingequipment.com/store/kits/ferrite-passive-di/

[spaceboss]

So simple, yet so beautiful. 

[GrindCustoms]

You're rocking it with your studio builds, are you planning some Mics, Pre..stuff like that?

[lincolnic]

You're rocking it with your studio builds, are you planning some Mics, Pre..stuff like that?

I am! I have two channels of Classic API's VP28 pres on their way to me right now. They'll be the most professional things I've ever built. When I save up some more cash, I want two channels of Hairball Audio's Lola pre as well.

I'm also considering doing Hairball Audio's 1176 clone, but that's more of a "this would be fun" idea for the moment. No mics on the docket for now, but I'm considering some of the DIY ribbon projects I've seen floating around.

[jkokura]

I'd love to do some Mic Pres as well, I just don't know how much of a difference it would be with the Convertors and preamps I use (Presonus).

Jacob

[GrindCustoms]

You're rocking it with your studio builds, are you planning some Mics, Pre..stuff like that?

I am! I have two channels of Classic API's VP28 pres on their way to me right now. They'll be the most professional things I've ever built. When I save up some more cash, I want two channels of Hairball Audio's Lola pre as well.

I'm also considering doing Hairball Audio's 1176 clone, but that's more of a "this would be fun" idea for the moment. No mics on the docket for now, but I'm considering some of the DIY ribbon projects I've seen floating around.

Nice, i've got a U87 and a pair of API512 on my project list......My only turn off with the studio pre at the moment is the expensive opamps other costly components....but they certainly worth the shot.

I'd love to do some Mic Pres as well, I just don't know how much of a difference it would be with the Convertors and preamps I use (Presonus).

Jacob

Those hi end preamp clones have a distinctive voice and wider dynamic range than most of the «ready to rock» interface.

The converters in PreSonus unit are good to go, if you use the Line Level Ins, you bypass the whole preamp section of it and everything is assigned directly to the converters.

[jkokura]

How hard would it be, and how expensive, to do a full vocal channel? I don't know much about where to get the resources. I mean, I could do a PCB if I had the schematic and datasheets for the parts...

Jacob

[GrindCustoms]

How hard would it be, and how expensive, to do a full vocal channel? I don't know much about where to get the resources. I mean, I could do a PCB if I had the schematic and datasheets for the parts...

Jacob

There's lots of schems on the gearslutz forum and on DIYRecording, most of the classic stuff is available from those place.

[lincolnic]

I'd love to do some Mic Pres as well, I just don't know how much of a difference it would be with the Convertors and preamps I use (Presonus).

Jacob

Seconding what Rej said on this. Real studio-grade equipment is night and day compared to the stuff that's built into most interfaces. I use an Mbox 2 Pro with my Pro Tools rig at home, and the pre-amps on that aren't great either. The good news is that if you have external gear, you can just plug it into your Line Inputs and bypass the built-in pres completely.

How hard would it be, and how expensive, to do a full vocal channel? I don't know much about where to get the resources. I mean, I could do a PCB if I had the schematic and datasheets for the parts...

Jacob

Assuming you want a mic pre, EQ, and compressor? You'd be in for well over $1000, by that point. A lot of this studio-level stuff uses components like custom transformers and/or op-amps, not to mention the cost of development and the like. You also have to consider additional requirements like power supplies and enclosures. Like pedals, most of the DIY studio gear out there is a clone of some other piece of gear. Some of it isn't produced anymore, or not readily available outside of a console - these are just a few reasons why it costs more. Think of it more like building an amp, compared to building a pedal.

The world of DIY studio gear is fairly new compared to DIY pedals, I think, so there aren't a ton of easy options available yet. You have to fall down a rabbit hole or two to find these things, I think.

Having said that, here are some rabbit holes for you:

DIY Recording Equipment - Start here. This site is run by a guy named Peterson Goodwin, who designed the DI and Reamp projects I've posted. You can find those here, but it's also a collection of DIY projects gathered from all around the web. So far, there are 285 links and counting. http://www.diyrecordingequipment.com

GroupDIY - You'll also probably want to spend some time here. This is where a lot of the DIY gear projects get thought up and worked out, by the hardest of the hardcore. If nothing else, you'll have fun checking out all the stuff people are building. http://www.groupdiy.com

Classic Audio Products of Illinois - these guys make the mic pre kits I have in the mail, recreations of 70s-era API pres. They're supposed to sound incredible. (Note that these kits are meant for a Lunchbox, or other 500-series enclosure, so that's an extra cost if you don't already have one. I wanted Lunchbox stuff for the portability factor, as I work both at home and at several different studios.) http://classicapi.com/catalog/index.php

Hairball Audio - home of the DIY 1176 project, as well as the Lola mic pre (another 500-series beast). http://www.hairballaudio.com/shop/

Seventh Circle Audio - I've never seen any of their stuff in the wild, but these guys are reputed to have a very good price/performance ratio. http://www.seventhcircleaudio.com/index.htm

Hamptone - like Seventh Circle, I've never used their stuff, but they have a good reputation. http://www.hamptone.com

[GrindCustoms]

^^Thanks for all those other links and sorry if i jacked your thread a bit.....i'm good at that...

I think that to get in recording equipement loop, you need to know what you need...not trying out stuff like we do with pedals...

Like lincolnic said most of those kit or available design are made in the 500 serie fashion, these don't come with a power supply, so you need to get a lunchbox or workalike with the PSU, thats another 200$ and up depending on how much space you need and if you go DIY aswell.

[jkokura]

Now this... http://www.hamptone.com/hvtp2_micpre.html

That is something I'd love to build. Problem is that it's like $1200 to buy the kit. Sorry, but at $600 a channel, I can happily make due with my Presonus pres. Unfortunately, like with most Pedal kits, we all know that the price doesn't actually reflect what we can do with our own sourcing. I also see that they haven't included their schematic anywhere, so I can't even do my own PCB and source my own parts.

Jacob

[lincolnic]

Now this... http://www.hamptone.com/hvtp2_micpre.html

That is something I'd love to build. Problem is that it's like $1200 to buy the kit. Sorry, but at $600 a channel, I can happily make due with my Presonus pres. Unfortunately, like with most Pedal kits, we all know that the price doesn't actually reflect what we can do with our own sourcing. I also see that they haven't included their schematic anywhere, so I can't even do my own PCB and source my own parts.

Jacob

Those are all entirely valid points. Depending on the company (if there is one), there isn't always as much of a culture of sharing as there is in the pedal world. Some of these guys operate strictly as a business (like Hamptone), and that's their right too. The other thing to take into account is the cost of this gear, even as expensive as it may be to most people, compared to the cost of buying a similar item off the shelf. You're right, it doesn't reflect what you can do if you sourced your own stuff, and I do think Hamptone in particular is a bit overpriced. A lot of the other things I linked to are actually great values, though (like the Classic API and Lola stuff I mentioned).

For better or worse, I think it's not quite the same market as DIY pedal building. Rej said it perfectly - you need to know what you need. You can build almost any pedal you want for reasonably cheap, just to try it out, but for stuff like this people tend to already be looking for a specific thing. And if it's a thing you can build, it's still probably two or three times cheaper than buying it.

Ultimately, Jacob, you're right - some of this stuff is out of reach for most people, but it's also not aimed at the average consumer. For a recording studio, ideally, the gear is an investment that'll pay for itself over time. It's still expensive, though. Every studio I know has to weigh its gear purchases very, very carefully.

And Rej, no worries about thread-jacking. I think we're actually still on topic anyway!

[spaceboss]

Those are all entirely valid points. Depending on the company (if there is one), there isn't always as much of a culture of sharing as there is in the pedal world. Some of these guys operate strictly as a business (like Hamptone), and that's their right too. The other thing to take into account is the cost of this gear, even as expensive as it may be to most people, compared to the cost of buying a similar item off the shelf. You're right, it doesn't reflect what you can do if you sourced your own stuff, and I do think Hamptone in particular is a bit overpriced. A lot of the other stuff I linked to are actually great values, though (like the Classic API and Lola stuff I mentioned).

For better or worse, I think it's not quite the same market as DIY pedal building. Rej said it perfectly - you need to know what you need. You can build almost any pedal you want for reasonably cheap, just to try it out, but for stuff like this people tend to already be looking for a specific thing. And if it's a thing you can build, it's still probably two or three times cheaper than buying it.

Ultimately, Jacob, you're right - some of this stuff is out of reach for most people, but it's also not aimed at the average consumer. For a recording studio, ideally, the gear is an investment that'll pay for itself over time. It's still expensive, though. Every studio I know has to weigh its gear purchases very, very carefully.

And Rej, no worries about thread-jacking. I think we're actually still on topic anyway!

True story: I started building pedals about a year-and-a-half-ago, so that I'd be comfortable building the classic API stuff. I've been so busy building pedals, and have spent too much $$ doing so, that I don't know if I'll ever even get to the Classic API stuff now. 

[selfdestroyer]

I came across this site for some PCBs of some pres

http://www.thediypill.com/store/index.php?main_page=index&cPath=65

This one caught my eye.

http://www.thediypill.com/store/index.php?main_page=product_info&cPath=65&products_id=193&zenid=gqdgj2ncqn1rd1cf8cbae1at61

[lincolnic]

True story: I started building pedals about a year-and-a-half-ago, so that I'd be comfortable building the classic API stuff. I've been so busy building pedals, and have spent too much $$ doing so, that I don't know if I'll ever even get to the Classic API stuff now. 

I hear you. I've been saving up for these guys, but in theory they'll eventually pay for themselves. I have a lot of tracking booked in the next month, so hopefully I'll be able to get these built and into rotation soon.

I came across this site for some PCBs of some pres

http://www.thediypill.com/store/index.php?main_page=index&cPath=65

This one caught my eye.

http://www.thediypill.com/store/index.php?main_page=product_info&cPath=65&products_id=193&zenid=gqdgj2ncqn1rd1cf8cbae1at61

Oh yeah. Jacob, I think that's the solid state version of the Hamptone guy.