Tubes and Headphones

[bluemeanies]

Here is a nice little tube headphone amp on Massdrop that won't empty your wallet.
If you are looking for tube amplifiers, mono-block or stereo that are designed, made, and built in the US and ARE affordable check out
tubes4hifi


www.massdrop.com/buy/appj-1502a-tube-headphone-amplifier?utm_placement=0&referer=UL4KPM&mode=guest_open&utm_source=Sailthru&utm_medium=email&utm_campaign=Automated%20Daily%20Promotional%202016-03-27&utm_term=Daily%20Promotional

[sidvicious]

Good find I wonder what the power output is, I'm currently using a SimAudio Moon 230 HAD, but thought about trying a Woo Audio WA-5.

[MusicHead]

Mar 27, 2016 12:06:50 GMT -5 sidvicious said:

Good find I wonder what the power output is, I'm currently using a SimAudio Moon 230 HAD, but thought about trying a Woo Audio WA-5.

The peak to peak output voltage is specified as 18Vpp, equivalent to about 6.3V RMS. That makes for 5W on 8 Ohm or 66mW on 600 Ohm, the two extremes of the specified output impedance.

[garbulky]

Mar 27, 2016 13:19:22 GMT -5 MusicHead said:

Mar 27, 2016 12:06:50 GMT -5 sidvicious said:

Good find I wonder what the power output is, I'm currently using a SimAudio Moon 230 HAD, but thought about trying a Woo Audio WA-5.

The peak to peak output voltage is specified as 18Vpp, equivalent to about 6.3V RMS. That makes for 5W on 8 Ohm or 66mW on 600 Ohm, the two extremes of the specified output impedance.

How do you calculate V RMS to watts or miliwatts? Not questioning you. I would like to learn please.
Do you know what it would be for 300 ohms? That's what my sennehsier does.

[MusicHead]

Mar 27, 2016 21:20:40 GMT -5 garbulky said:

Mar 27, 2016 13:19:22 GMT -5 MusicHead said:

The peak to peak output voltage is specified as 18Vpp, equivalent to about 6.3V RMS. That makes for 5W on 8 Ohm or 66mW on 600 Ohm, the two extremes of the specified output impedance.

How do you calculate V RMS to watts or miliwatts? Not questioning you. I would like to learn please.
Do you know what it would be for 300 ohms? That's what my sennehsier does.

No problem, I work with this stuff. Glad to share the tricks of the trade with fellows Emotivans :-)

It is simple, actually, these are quite common conversion equations:

Vrms = 0.3535 * Vpp

P= V^2/R

So, for you 300 Ohm headphones:

0.3535 * 18 = 6.363V (same as before)

P= 6.363 * 6.363 / 300 = 135mW

There are many webpages with a more thorough explanations and online calculators. I also have an app for my Android phone, just because it makes the process faster :-)

www.referencedesigner.com/rfcal/vrms-to-vpeak-conversion.php

www.bcae1.com/spkrimp.hthtm

play.google.com/store/apps/details?id=com.appdevgenie.electronicscalculator&hl=en

[garbulky]

Mar 27, 2016 21:56:19 GMT -5 MusicHead said:

Mar 27, 2016 21:20:40 GMT -5 garbulky said:

How do you calculate V RMS to watts or miliwatts? Not questioning you. I would like to learn please.
Do you know what it would be for 300 ohms? That's what my sennehsier does.

No problem, I work with this stuff. Glad to share the tricks of the trade with fellows Emotivans :-)

It is simple, actually, these are quite common conversion equations:

Vrms = 0.3535 * Vpp

P= V^2/R

So, for you 300 Ohm headphones:

0.3535 * 18 = 6.363V (same as before)

P= 6.363 * 6.363 / 300 = 135mW

There are many webpages with a more thorough explanations and online calculators. I also have an app for my Android phone, just because it makes the process faster :-)

www.referencedesigner.com/rfcal/vrms-to-vpeak-conversion.php

www.bcae1.com/spkrimp.hthtm

play.google.com/store/apps/details?id=com.appdevgenie.electronicscalculator&hl=en

Okay so first you take 0.3535 * whatever the peak to peak volts to give VRMS.
Then
You do VRMS divided by impedance output to give you teh milliwatt value.
Would I be correcty that if I'm looking for watt vallue At the very beginning I multiply
3535*peak to peak volts instead of 0.3535?

[MusicHead]

Nope.

0.3535 is the coefficient to convert Vpp to Vrms.

Then you square the Vrms (same as multiplying by itself) and divide by the Impedance. That will always give you the result in Watt.

I should have more correctly written the result of the equation as 0.1349 Watt, which can also be expressed as 135mW (rounded).

[garbulky]

Mar 27, 2016 22:44:28 GMT -5 MusicHead said:

Nope.

0.3535 is the coefficient to convert Vpp to Vrms.

Then you square the Vrms (same as multiplying by itself) and divide by the Impedance. That will always give you the result in Watt.

I should have more correctly written the result of the equation as 0.1349 Watt, which can also be expressed as 135mW (rounded).

OK gotcha. So the step I was missing was squaring the Volts RMS