DIY cheap 9v preamp for dual source MIC

[rschultz]

Version 2 of the box. I started with a Hammond 1590G, only slightly bigger than original 1590A. It's tight, but it does fit a battery and 2 jacks. Although I tried the jacks coaxial and that didn't work so I had to mount the output jack on top.

[rschultz]

Version 3:3D Printed

I modeled this up based on the 1590G box. But instead of machining the holes, it just left them blank. The only thing I had to do was tap the 6-32 screws, which was super easy in PLA+. Cutting the square battery hole was a PITA, this is much better. And bonus, it’s non conductive so I don’t have to worry about things shorting out!

[BernardG]

rschultz... I also have an HX Stomp, which I'm using it with an electric, and I'd be curious to hear how your setup sounds with it. Any audio clip somewhere?

I just installed a Barbera nylon in my Ovation, about to install a steel one in my Larrivée, there are good chances that I add mics in both, and I'm looking at my options—before amplification.

[rschultz]

Originally Posted by BernardG

rschultz... I also have an HX Stomp, which I'm using it with an electric, and I'd be curious to hear how your setup sounds with it. Any audio clip somewhere?

I just installed a Barbera nylon in my Ovation, about to install a steel one in my Larrivée, there are good chances that I add mics in both, and I'm looking at my options—before amplification.

No I don't... but maybe this weekend I'll create some.

[BernardG]

I'd like to hear that. In the meantime, I'll start to experiment. If I could get away—and be happy enough—with essentially only using the Stomp when playing acoustics live, that would simplify things.

[rschultz]

Not to hijack my own thread, but just a quick word about the Stomp. I used to have a $3000 electric board and a $1000 acoustic board. Now my $400 stomp does everything I ever needed and more, 100x more options than those past boards. I had various acoustic preamps; Baggs Session/Para DI/Venue, Grace Felix, Fishman Platinum Pro, etc. People talk about preamp quality, I just don't hear any difference.

So I was where you are about 5 years ago... wanting to simplify. I started with the Helix Floor, but it's big and heavy and when the stomp came out and upgraded the number of blocks you could have to 8, I sold it for the Stomp XL... and eventually downgraded to just the Stomp. Electric presets, acoustic presets, dual source presets, sometimes I plug in a dual-source acoustic in the top and an electric guitar in the return... each patch knows what input to take. I have an Airturn footpedal, which switches songs on my iPad and then my iPad sends a bluetooth signal to Widi-Master (midi in Stomp) that switches to whatever patch and snapshot I want for that song.

I lead music at my church most Sundays. I have a normal school backpack that I get all my stuff in: 5 binders for musicians, iPad, Airturn, 2 button switch I stick in Stomp exp jack (to cycle through 4 basic screens), Stomp/PS and iPad holder. That over the shoulder and a guitar in hand. I couldn't do that with the Helix (too big/heavy), and obviously the pedals boards are even bigger.

I've had probably 15-20 different pickups in my acoustics over the years, a lot of dual source combinations... all through Helix or Stomp. And now with this super cheap and easy way to power a condenser mic with 9v, that's the icing on the cake for me. It noticeably brings out the high end sparkle and clarity when I fingerpick better than the Barbera can alone... and the Barbera with an IR sounds pretty good by itself for a UST. Anxious to install a mic in my other guitar with a K&K.

Of note, the recent firmware helix upgrade significantly reduced the processor requirements for most blocks... AND added some interesting IR functionality that I haven't explored yet. Stomp + IR for acoustic is awesome.

[Doug Young]

I'd love to hear a demo with your Helix. It seems like it could be a nice box. I tried one when it first came out, and it didn't go well, but so many seem to like it, I'm assuming I got a defective unit.

[BernardG]

Thanks for the detailed input about your setup with the Stomp, rschultz. Good to hear.

If you care sharing which IRs you use for the acoustic, I'd like to know. I see that there are some available here and there, yet since you already use some that you find satisfying, it would be useful.

I did the Stomp update a couple days ago, and yes it's good news that they managed to lower the DSP usage.

PS: I installed the Barberas today in my nylon and steel guitars. I'm testing the steel right now. First impressions... I'm surprised of how much, unamplified, the saddles themselves brighten both guitars' sound. Not in a bad way, though I personally like a darker sound with any guitar. The amplified sound on the other hand is the best I heard so far (and I could test it against K&Ks and a Lyric, while I used several other brands in the past). I installed them myself, which was a little tricky, what with some of the wires being real tiny. And then, though it should have dropped right in, I had to widen the slot in my Larrivee with sandpaper as it was a tad too narrow. Anyhow, all in all I'm happy with this upgrade.

[rschultz]

Here is a short clip 5 different ways on my Furch:
1. Barbera pickup, dry and unaltered
2. Barbera with custom IR (60% mix) from Cuki79/JonFields45 collaboration, LPF, HPF, mild EQ
3. Internal mic powered with 9v - HPF @ 300 Hz.
4. Both mixed together, still fairly dry, no reverb. Just HLP, LPF, mild EQ
5. with reverb

The sample 1 is slightly louder than the rest, I probably need to boost my IR block a bit. Samples 2-5 all have the IR block on.
I can hear a bit of high pitched warble with the mic on that isn't there with just the pickup, I'm picking up noise somewhere. Hard to hear while playing, but it's there during the spaces mark 0:45-0:47.

[rschultz]

While I've got all the recording stuff hooked up, here's a song we're singing tomorrow. This is the Helix setup I'll have running: Barbera, IR, internal 9v mic, bits of EQ.

I should say that my level of experience: playing, recording, processing, etc. is probably fairly average. I know a lot more than I did 15 years ago, but still not anywhere near the level of a lot of people on this forum. So feel free to make suggestions, always looking for a better sound.

I was able to do some post processing to make it sound a bit better, but I'm a novice in this area.

[rschultz]

Originally Posted by BernardG

If you care sharing which IRs you use for the acoustic, I'd like to know. I see that there are some available here and there, yet since you already use some that you find satisfying, it would be useful.

I recently asked Cuki and Jon Fields to create custom IR's for both my guitars based on recordings I gave them. They both gave me great options to explore with their files.

If you're just getting into IR, I got a lot of mileage out of a 3Sigma IR I bought years ago. $15 will get you a lot of files to play with in your Helix.

[rschultz]

I spent some time troubleshooting that high pitch warble I heard on the mic, and found that it is due to how I am powering the Turbo Tuner. It's the only extra pedal I add to the Helix... the Helix tuner is fine, but I think the TT is better (people have disagreed with me about this, YMMV). Ever since I've had the Stomp, I've simply daisy chained the tuner power to the Helix power and for the most part it works.

Anyway, not sure why it only happens with the mic, but when I remove the tuner from the circuit the warble noise goes away. So I have ordered a Cioks Sol that will have isolated power for the Helix, and tuner, AND I can power the mic this way too.

[rschultz]

I re-recorded the above 5 samples without the tuner in the circuit. Sounds much better.

1. Barbera pickup, dry and unaltered
2. Barbera with custom IR (60% mix) from Cuki79/JonFields45 collaboration, LPF, HPF, mild EQ
3. Internal mic powered with 9v - HPF @ 300 Hz.
4. Both mixed together, still fairly dry, no reverb. Just HLP, LPF, mild EQ
5. Both with reverb and mod

[Doug Young]

Thanks, these sound pretty good. My favorite is probably just the Barbera with the IR, tho you can certainly the added air from the mic.

[rschultz]

FWIW, I measured the battery voltage to see how long it would last. A fully charged rechargeable is 8.20 vdc. After 8 hours of being plugged in and played most of that time, I remeasured at 8.19 vdc. It's true rechargeables will maintain their voltage better than alkaline even though their charged voltage is less. But still, the current draw for either is extremely small. I read online that electret condenser mics have a current draw of <0.5 mA. It would seem that a battery would last a very long time.