Search found 13 matches

by Audio1Man
Sat Sep 14, 2019 11:40 am
Forum: Build
Topic: Audio RMS versus Peak
Replies: 21
Views: 1193

Re: Audio RMS versus Peak

In Pro Audio I would not use rail to rail op amps. Look @ the THD/SPECTRUM of the output as output level increases. Many op amps will go nonlinear when the output gets near to 3 volts from the rails voltage. To get clean 8v rms the op amp rails need to be slightly larger than 15 vdc.
Duke
by Audio1Man
Mon May 27, 2019 9:51 pm
Forum: The Peabody Lounge
Topic: Pro Audio Design Forum taught me all I know, can I build anything without getting sued?
Replies: 8
Views: 1577

Re: Pro Audio Design Forum taught me all I know, can I build anything without getting sued?

Hi JR As JR Said Arguably "work for hire" inventions are property of the employer, but plenty of gray area and best negotiated before the fact, rather than after. I did have an agreement prior to starting, however I made & sent the project before all of the paperwork was sent back to me, so it was m...
by Audio1Man
Mon May 27, 2019 12:35 pm
Forum: The Peabody Lounge
Topic: Pro Audio Design Forum taught me all I know, can I build anything without getting sued?
Replies: 8
Views: 1577

Re: Pro Audio Design Forum taught me all I know, can I build anything without getting sued?

Hi KMN I don’t have a problem building patent ideas or Copyright and verifying that it will work in my application. I have not used patent ideas or Copyright for production products without paying a royalty. As JR said “pay it forward, we all started ignorant and had some mentoring along the way.” I...
by Audio1Man
Sat Apr 27, 2019 6:12 pm
Forum: Test, Measurement and Repair
Topic: HP3582A
Replies: 3
Views: 1200

Re: HP3582A

The HP3582A was a great instrument years ago, however with 25kHz BW and 70dB dynamic range almost any Sound Card will be a better instrument for today's jobs and much smaller.
by Audio1Man
Sat Apr 27, 2019 4:19 pm
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 492
Views: 193850

Re: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851

Wayne

What about placing the BIG TX into a 5 Gal steel paint can? This may give you another 10-20dB reduction.
by Audio1Man
Fri Apr 26, 2019 6:01 pm
Forum: Pro Audio Design
Topic: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851
Replies: 492
Views: 193850

Re: A Low Noise Balanced Input Moving Coil Preamp Using the ZTX851

Hi Wayne
Is the “HUM” Electrostatic or Magnetic? What is the difference in FFT by wrapping the pickup in Alum foil vs putting it in a steel paint can and closing the lid? What is your area lighting type? Incandesce, fluorescent tube or switching fluorescent / LED type?
Duke
by Audio1Man
Sat Apr 06, 2019 4:26 pm
Forum: The Peabody Lounge
Topic: karma
Replies: 8
Views: 1446

Re: karma

I don’t have a meter reading problem anymore, where the gate is left open. Gas, Water & Edison are all Smart Meters. Most problems I see are if it is heavier than I phone it’s too much work, even if they have an APP. One of my grandson’s was on that road until he understood and he got into a trade s...
by Audio1Man
Mon Apr 01, 2019 12:28 pm
Forum: Test, Measurement and Repair
Topic: Welcome to the Test, Measurement and Repair Forum
Replies: 11
Views: 3553

Re: Welcome to the Test, Measurement and Repair Forum

I was listing to my music system this mourning and it failed. My system consist of Electro-Voice SP13.5RBXWK Rearaxial Softspeaker driven by a Crown Belchfire BF6000SUX with the Rane P1 14 Pseudoacoustic Infector preamp with the Jensen's JE-EP-ERs Multi-denomial Transpedance Informer input stage (I ...
by Audio1Man
Sat Mar 16, 2019 1:14 pm
Forum: Test, Measurement and Repair
Topic: AP System One Front End
Replies: 1
Views: 1066

Re: AP System One Front End

OK, not many persons got this. Bruce spent lots of time correcting several small errors that make small improvements that give the total system performance. There are others tricks and when another Mfg copied the special tricks this stopped all schematics/service information being released. The Syst...
by Audio1Man
Mon Mar 04, 2019 4:50 pm
Forum: Pro Audio Design
Topic: Preventing mic preamplifier HF oscillation
Replies: 7
Views: 2306

Re: Preventing mic preamplifier HF oscillation

A small resistor in each BASE will DQ the circuit and will add some noise. You can also add a ferrite bead to each BASE this will also DQ the circuit. C1 & C2 could be smaller. With SMD layouts the BW always is much higher and amplifiers have a better chance of becoming an oscillator. When the phant...