FAQ: UA Bock Microphones

General Information


What sequence should I follow when powering up my tube mic?


1. Mute console or speakers (headphones).

2. Place mic securely in shockmount on stand.

3. Connect multipin cable between mic & power supply.

4. Connect 3-pin xlr cable between power supply & console or preamp.

5. Connect AC cable to wall & IEC 320 connector on power supply.

6. Turn AC power switch on psu “on”, wait 1 minute.

7. Unmute, set levels, and record!


Should I warm up my mic?


It is not necessary to warm up a FET mic, but we recommend warming up tube mics for 5-10 minutes.


Should I hang my tube microphone upside down?

It is not necessary to hang your tube microphone upside down. They may be positioned any way you prefer.

PRO TIP: Hanging the microphone upside down leaves room below for a music stand with lyrics, tablets, etc.


What is proximity effect & why is it important with UA Bock microphones?

Proximity effect is an increase of low frequencies at close distance. This is important with UA Bock microphones because the slope of the low frequency response at typical user distances has been carefully engineered to flatter the vocalist. The FAT switch follows this design goal by adding a low-end boost between 10 Hz and 400 Hz while also removing the high boost.


When did UA acquire Bock Audio?

Universal Audio partnered with David Bock and acquired the Bock Audio and Soundelux brands in 2020.


Are the UA Bock microphones based on any Soundelux or Bock Audio designs?


Yes. The first three microphones in the UA Bock line follow their Bock and Soundelux brethren in almost every way. See details in each mic’s Knowledge Base article. 




Why does my microphone sound like surf (or the ocean)?

You probably have a bad tube.


Can I change the tube myself?

Tubes are preselected, burned in using a proprietary process, and then re-tested before final approval. Also, the heater voltage each tube requires is unique and factory adjusted. Interchanging supplies could lead to heater under or over voltage conditions, which in turn could lead to either less than ideal noise performance or degraded (shorter) tube life. Different tubes have different current requirements, so an adjustment for one tube might not even power up another tube, and the same adjustment could overheat another tube.


How long should I expect a tube to last for?

Tubes can last years or even decades based on usage. Our tubes carry a one year warranty from original purchase date, and should be expected to last for years beyond that.



Power Supply Units (PSU)


Are your power supplies interchangeable?

Generally speaking, a new UA Bock power supply will work with a new microphone of the same model. However, each power supply is adjusted to the specific microphone it's paired with for optimum performance. 


I own two UA BOCK 251's, can I mix & match the PSUs?

No, and it's a good idea to somehow mark your mics and supplies so that they don't get mixed up.


I own a UA Bock 251 and a UA Bock 167, can I swap the PSUs?

No. Each microphone uses a different tube type, and each power supply is designed to work with that specific tube.


How do I change the fuse on my P-251 or N470 PSU?

Unplug the power cable and remove the small drawer in the IEC module. Inside you will find a spare fuse, which should be used to replace the current fuse.

Hardware Connection


Do I have to use a solid state preamp with a tube mic?

No. Any microphone preamp will work.


Is it OK to use a tube preamp with a tube mic?

Absolutely! Some of the best vocal recordings were made this way.




I bought a used BOCK Microphone, does it have a warranty?

Standard warranty is two years with a one year for warranty for tubes. Original invoice is required.


Where can I order new elastic for my shockmount?

Contact UA Customer Support here


Do you service Bock Audio or Soundelux microphones?

Yes, if under warranty. Otherwise through recommended service centers.

Name Studiocare (UK) Microphone Repair (US) Mikrofonservice (EU)
Contact Chris Kelly David Brown Michael Amon 
Address Studiocare Professional Audio Ltd
56 Evans Rd
Speke, Liverpool L24 9PB
United Kingdom
Microphone Repair
30473 Mulholland Hwy. #56
Agoura Hills, CA 91301
Dr. Karl Rennerstr. 29
2232 Deutsch Wagram. Austria
Telephone T: +44 (0) 151 707 4545
T: +44 (0) 845 345 8910
Office: (818) 706-0156
Cell: (818) 746-6481
+43 664 215 38 55
Email workshop@studiocare.com MicrophoneRepairLA@gmail.com office@mikrofonservice.at
Hours M-F: 9:30AM - 5:30PM M-F: 10:30AM - 4:30PM  



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