Build and Review: DIY Dual Mic Preamp (ESP P-66)

[@richardrgoodwin]

Best live 'magic smoke' capture I've seen in a while!

[@Juksemakeren]

10:27

[@4211Rob]

Excellent! As a woodworker, I always measure at least twice and as a circuit builder I check many more times. Also I like Linear Technologies LT1086 positive regulator over the lm317. However I love Li-ion batteries on a split rail. ESP is excellent. I have made his power amp and hope to do his preamp with tone controls next. Now if we can get more electricians to sing on KZbin, I'd give that a thumbs up to that too:). Cheers, Rob

[@searchiemusic]

when you said 'you only need 4 mics for drums' i started sweating, i can barely manage 16 tracks on my reel to reel lmfao

[@ToysForTheGods]

I really appreciate the video. I have only two things to add from my perspective. Motherboard stand offs are super cheap and you can usually just drill an appropriate hole and they will almost always cut their own threads. And I do plan on building this almost identical to what you have done here but with combo XLR output jacks instead of 1/4" just for versatility.

[@benridgway3686]

I had to watch the magical smoke release three times. Normally I only get to see the results but not the process.

[@extralifedisco]

Took me by surprise! Wish I'd shot it in 120fps lol

[@uriel-heavensguardian8949]

Thank you for sharing this! This was an awesome watch!

[@mikeywilde]

I didn't expect the amazing ending! Thank you for that!

[@dez5]

incredible video, love it. Great song as well,

[@iblesbosuok]

Twist cables which connect pin#2 and pin#3 from XLR sockets to PCB. Pots cables also. Would increase interference immunity. It is better to choose insulated sleeve output sockets to avoid ground loops. Use single ground connection between chassis and circuit's ground. Use deserve quality 1:1 signal transformer to get floating balanced output. Sorry for my terrible language.

[@CarlosYounes]

Nice! Gosto muito dos projetos ESP. Muito honestos e sérios. Parabéns pelos trabalhos eletrônicos e músicas. The best regards Cheers from São Paulo - Brasil

[@bpn12123]

Great build but most importantly GREAT cover at the end. Any chance that you upload the whole song? To my ears, your voice suits it better than the original.

[@MegaCadr]

I like how you specify “not successful”:)

[@GeoffBosco]

“Four preamps should be all you need to record live drums.”

[@to.ps2906]

Please let me know how many amperes I use with this circuit. Thank you

[@ivolol]

Would have been nice if they put a simple Widlar transistor current sink in the design underneath the differential transistor pair, instead of just 2.2k resistors, usually really ups the CMRR

[@drcarrot415]

Is there a way to wire this up to have balanced outputs instead of unbalanced? Might’ve missed something, but I’d find a balanced output more useful in a more professional setup

[@extralifedisco]

Yes, there is a separate balanced driver board available from ESP (project 51: sound-au.com/project51.htm . For the short cable run I have I wasn't too concerned about the signal but it would definitely improve the noise floor. I didn't really have room for another PCB in the case but perhaps with a smaller PSU board it could be made to fit.

[@drcarrot415]

@@extralifedisco awesome! My main concern is my interface, for whatever reason it sounds horrible using any unbalanced source, but balanced sounds lovely. Thanks for the response!!

[@ikaisoha2700]

Wow good job

[@ivanmaskov]

I was planing to build this preamp for years :) great stuff diy perks also made it but portable version for field recording.. Also i have steinberg,it has great preamps color wise but lot of noise, it has 2068d jrc opamp i am planing to upgrade it with lm4562 bi texas instrument.. Can you make video of you upgrading yours? I have low knowlage of eletronics

[@extralifedisco]

Thanks Ivan! Battery power would be a great upgrade for the preamp, probably help a little bit with performance as well if you use 2 9Vs for bipolar power. I haven't tested the steinberg too much as far as its preamps, but I'm not too picky about noise. I did see Julian Krause's review where he says their self-noise is about -123dB compared to -129dB for comparable stuff from Behringer, NI, etc. I don't know enough to say whether this is a factor of the op amp selection or another part of the circuit, but if I find the recordings I get are too noisy for my liking I'll certainly look into modding it. I expect all you would need is a hot air station and a steady hand. Krause's review: kzbin.info/www/bejne/hoTEY2qeoM9mfZo

[@finonomastropiero4261]

So a +/-12v psu would fit for this project isnt it?

[@extralifedisco]

Yes it runs on a 12VAC supply into a +/- dual dc adapter board, much like euro rack supplies (e.g. MFOS wall wart)

[@symdega]

This was sweet. Thanks a lot

[@mike105172]

Maybe be a dumb comment but how do you connect the xlr jack to the circuit? I’m mainly confused on the hot/ cold wiring and where it goes and what is the point of it?

[@crancarenotafish]

How? With wire. Is a balanced preamp so it has a designated connectors to hock the wire. One is hot and another is cold. Check author's website, project 66

[@finonomastropiero4261]

If the preamp works well with two 9v batteries, then +12/-12v psu should also do, right?

[@finonomastropiero4261]

Great video btw. Awesome cap exploding shot

[@extralifedisco]

Yes, +/-12 is what I'm using it with. I think the op amps are rated for their lowest noise at +/-15V.

[@aldadanger802]

I see that is +12 gnd -12, how you can put 12vac adaptor on it? Tell me please thankyou

[@finonomastropiero4261]

@@aldadanger802 try moritz klein diy psu

[@businessenglishteacherus]

Just one Q: does it sound GREAT?

[@uniaoinstrumentosmusicais]

Da hora esse som que você gravou, parabéns... o capacitor explodindo foi um show a parte, kkkk. Um abraço

[@ZeroesandOnes]

10:29

[@extralifedisco]

destroyed in seconds

[@ZeroesandOnes]

@@extralifedisco shame YT doesn't let you embed by the frame, i was using , and . to move around

[@mariasant7852]

MUITO BOM