I've been happy with my tone for years, until I watched this video. Thank you.

best impendance related video ever, thanks Frode! also hilarious as fuck...

i'm 50 seconds in and already in tears. thanks!

Incredibly amazing! I can't even believe this lesson was given for free. Keep the amazing job and I'm sure this channel will certainly thrive. :)

One of the most thorough videos on this topic. And I`m impressed by your English. Your pronouncification is almost impeccable! Way to go Frode!

Brilliant Frode. A much needed tutorial.

High-level professional and very useful video. Thank you very much for this test! I own the Prodipe…

Tusen takk for en super opplæringsvideo 👍🎶😊

This is some great advice. I've long been a proponent of 10M ohm for piezo pickups, particularly for bass, cello and guitar. With the latter two it may be less critical, and for violin, mandolin or similar instruments with no bass fundamentals a 1M ohm input is likely adequate, but there's no harm in using a higher impedance. As for the pickups themselves, the impedances are more complex than can be expressed with a single ohm value, use of which implies that the impedance is constant across the frequency range of the instrument as though the impedance is only made up of resistance. Piezo pickups present a series capacitive reactance, so the pickup total impedance rises as the frequency of the signal goes lower. Magnetic pickups, on the other hand, present a strong series inductive reactance, so their impedances rise with frequency. The solution, as you say, is not to match these complex impedances, but rather to bridge them with one much that's much higher. Technically this is because we're looking to get a flat response based on the voltage that a pickup produces, not maximize power transfer which is what matching provides. A too low impedance input becomes a filter, reducing the signal as the pickup impedance rises with lower (piezo) or higher (magnetic) frequencies. I'd be interested in trying a high quality passive direct box, not because that's likely a successful approach, but because I'm curious how much the other frequency anomalies you noted are due to the cheapest small signal transformer some indifferent corporation could wind, or to what extent those were due to the kinds of complex impedances that even a high quality transformer will present to a piezo pickup. For me, the take away here is that, in order to minimize problems interfacing with different sound systems that may be encountered out in the wild, one would do well to travel with an active direct box. That ought to feature a 10M ohm input impedance along with a high quality output transformer and a ground lift switch. It should also have its own power (and carry spare batteries!) so you don't need to rely on having either phantom power from the main sound system or an AC outlet on stage. That way, even if all else fails you can still provide the sound system operator with a high quality, balanced signal. Basically it puts the bass player in control of everything they can control.

Thank you Frode!!! This was super helpful.

This is the video i have been waiting for!

Thank You for this explanations. God bless you. :-)

Glad I could help you with this project. There is too much folk-law and myth (AKA bullshit) on the Internet. Its good to get some technically correct information out there. Cheers Ian DuRieu The Leon Audio Co.

I use a mic and a preamp to power my mic.. I really don't dig that di/pickup sound on an upright.. I love the acoustic/ambient organic sound.. I guess that's what the Marsalis dig as well..

The difference in tone between that passive DI and your preamp's 10M ohm input was obvious even on tablet speakers. Those tiny speakers couldn't even hide the bass rolloff caused by connecting to the transformer.

I have an Audix F90 gooseneck condenser that I’ve modded to friction-fit between the strings right by the tailpiece, and it sits under the strings behind the bridge and points at the soundboard directly below the bridge. It is powered (and controlled) by a Behringer mini mixer. From there it goes into (depending on the scenario) either a Crate BX100 combo or a Hartke HA3500. Both those amps have contour controls as well as multi band graphic EQ. And in both instances I’m very happy with the amplified sound. Is it perfect? No. But is it loud and clear enough across the entire range of the instrument, without intrusive resonant peaks, to work with small or large combo groups? Yes. It sounds more acoustic by far than any piezo-type configuration I’ve tried.

Veldig lærerikt! Supert!

Good video.

Dødsbra, keep it up :-)

Thank you so much for this. I wish I had seen this about 10 years ago... I have come to much of these same conclusions myself - however this has further cleared up some confusion. Tell me - do you know what the output inpedance of the Fishman Full Circle is?

Great video thanks. It looks like you can't use the PZ DI with just a bass amp as there would be no phantom power. Can you recommend a different 10MEG buffer that has a power supply other than phantom. Thanks

Amazing Frode!!! Thank you so much for all the precious information. What's your line sequence between the doublebass and the amp?