#31

well, given I’m sat on a terrace on holiday and this is still at the back-of-a-cigarette-packet stage, I’m just going to see how it turns out. Possibly do some prototyping. Possibly read the paragraphs about layout in section 10 of the datasheet.

I mean, it’s probably not going to be cheaper than anything available or better, so maybe it’s just fun, and when I fuck it up you can tell me you told me so.

2 Likes
#32

Heh, I wouldn’t be the one to do that, but mostly just curious as to what your strategy is for it. Good on you for trying, for sure!

#33

Actually, I have an idea to use a common camera battery like an LP-E6N to power a device like this. You could easily charge it with a canon charger or we could build a little USB charging circuit into the device, also useful for side power. That way the batteries would be cheap and removable. You could do it with rechargeable AAs too, but those don’t hold as much power for their size. I’d be interested in helping you sketch this up, if you’re up for some help. With a battery you have less power supply issues to be concerned with - mostly just eliminating the switching frequencies and their harmonics from the booster circuit and the chip supply, and ensuring good board layout. A full ground plane on one layer will help with that, too.

#34

oh, arse. I misread things. So the main issue is that the nice available mic preamp chips want meaty bipolar supplies. So now I’m investigating bipolar DC-DC converters along with the bloody 48V supply…

#35

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#36

I use my zoom h5 as a portable pre amp and also for getting external sources into my modular.

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#37

Since the new Mixpre recorders are out there is less demand for the original Mixpre (the one before the Mixpre-D). They go on ebay for about £250 these days. Highly recommended, all analog, battery powered, metal chassis etc…

1 Like
#38

I have a Mixpre-D I bought of eBay and use it all the time for lots of different routing, pre-amp bypass my Organelle dac and use it as a soundcard. Be aware though, it eats AA batteries in no time.

I’ve looked at these often too https://www.eventideaudio.com/products/stompboxes/mic-pre-fx-loop/mixinglink just no phantom power of 9V

#39

in the field i find i get through 4-5h (half a day) with one 48V supplied boom mic, with standard (white) eneloops
At home i use power it off the mains with a hirose-fitted power supply.

#40

Bit of a bump a few months later, but what are people using as mobile preamps with their norns?

Would be great to have a single channel high quality preamp that’s DIY-able.

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#41

I bought a used ROLLS mini mic pre which seems to work really well. It’s not battery powered but provides full phantom.

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#42

Interesting.

How is it in terms of noise?

#43

Hard to say. I haven’t used it to record very quiet sounds or used any mics that require a ton of gain. But I haven’t had any noise issues so far.

#44

Did you get anywhere with this in the end?

I was also looking at something like this:

It’s a shame there doesn’t appear to be much between DIY/supercheap(/crappy) and the Sound Devices MP-1, which is crazy expensive, and pretty big for a mobile preamp.

#45

I spent an afternoon at the LOM Audio space a few months back and got into a conversation with Jonáš about the That 1512/1510 Preamp circuits, which he described as a pretty solid option (likely better than most ce field recorder preamps).

there’s some kits of that circuit floating around, although I haven’t found one yet that can run off USB or battery power. might be an interesting place to start though…

1 Like
#46

Ah cool. I hadn’t come across the 1512/1510 before. A quick googling led me to some schematics and such, but indeed, didn’t see anything for USB or battery power.

I guess that’s the bottleneck here, as there are plenty of DIY preamps out there, just not in this formfactor/featureset.

#47

not really. I think it all might have been fantasyland bullshit, ie, lots of things connected up on a circuit board that would probably be unusably noisy. analog electronics is not my strong point, and I was possibly just doodling on holiday for doodling’s sake.

#48

Its been mentioned a few times before, but the Zoom H5/H6 really pairs nicely. I use my H5 as a portable 4 channel mixer with preamps. My only regret is I kinda wish I’d gotten the H6 for the additional channels. H5 was $200ish used, I think.

1 Like
#49

Has anyone ever come across a Shure FP23? It looks identical (literally) to the Sound Devices MP-1, and although it’s discontinued might be an alternative as well.

edit:
I bit the bullet and ordered a used one off eBay and will report back.

On a side note, does anyone have any experience with rechargeable batteries in things like these? Do they hold up/work out well? Any specific brands? I remember my Zoom flying through rechargeable batteries like a decade ago, but I figure batteries have gotten better since then.

#50

Another potential candidate in this space graced my inbox today: https://centrance.com/store/MicPort-Pro-2-Mobile-Recording-Interface-p129318859

Their products are somewhat unique given the built in battery power.

I can’t vouch for quality or their ability to deliver but I figured others might be interested (I backed a successful kickstarter of theirs for a mobile battery powered pre which the company ultimately failed to bring to market)