Review: JDS Labs O2 (Black edition) + O2/ODAC discussion - Page 8

Is there any laptop that seriously uses an adapter with AC output?  Why waste space and weight doing AC/DC conversion inside the laptop?  All the internal components run off of various levels of DC (so there are DC-DC step-down converters), and you want DC to charge the battery anyway.  Desktop computer ATX / BTX / whatever spec are all DC power.

If you're getting (buying) a new AC adapter, you may as well spend a few dollars extra on the beefed-up part, WA16-1000:

http://www.mouser.com/ProductDetail/Triad-Magnetics/WAU16-1000/?qs=sGAEpiMZZMtpkqKkT5w3uqH3NkAtJ%252bfiB%252bEoemwjDP0%3d

That's way overkill, but default WAU12-200 is a bit marginal if charging the batteries and running high power outputs.  It's probably plenty okay for most uses, which is why it's default, but it's just to save a few bucks.

There are many happy LCD-2 users using the O2. It has power to spare to drive the LCD-2 to hearing damaging levels and beyond.

The LCD-2 hits 110 dB with about 1 volt of input. Peaks of 110 dB are considered plenty loud by most people (hearing damage starts past 85 dB). 110 dB is standing on a sidewalk next to a jack hammer tearing up concrete.

Even if you plan for 115 dB peaks, which is extremely loud, you only need about 1.7 Vrms which is 0.048 watts. The O2 can provide 5+ Vrms which is good for 124 dB SPL with the LCD-2. And that's running from battery power.

So just on batteries alone the O2 will dirve the LCD2's to their limits and ear damaging levels.

There is not shortage of bass with the O2....if its there in the recording it will get amplified and if your cans can reproduce these low frequencies you will hear them!

Alex

Quote:

Originally Posted by adydula 

There are many happy LCD-2 users using the O2. It has power to spare to drive the LCD-2 to hearing damaging levels and beyond.

The LCD-2 hits 110 dB with about 1 volt of input. Peaks of 110 dB are considered plenty loud by most people (hearing damage starts past 85 dB). 110 dB is standing on a sidewalk next to a jack hammer tearing up concrete.

Even if you plan for 115 dB peaks, which is extremely loud, you only need about 1.7 Vrms which is 0.048 watts. The O2 can provide 5+ Vrms which is good for 124 dB SPL with the LCD-2. And that's running from battery power.

So just on batteries alone the O2 will dirve the LCD2's to their limits and ear damaging levels.

 

There is not shortage of bass with the O2....if its there in the recording it will get amplified and if your cans can reproduce these low frequencies you will hear them!

 

Alex

Interesting. Maybe the listeners were used to a warmer-sounding amp then. The meets here in Seattle tend to have a lot of tube amps (from Schiit to Woo). I'll have to try it out whenever the next meet is! ^.^

Quote:

Originally Posted by adydula 

There are many happy LCD-2 users using the O2. It has power to spare to drive the LCD-2 to hearing damaging levels and beyond.

The LCD-2 hits 110 dB with about 1 volt of input. Peaks of 110 dB are considered plenty loud by most people (hearing damage starts past 85 dB). 110 dB is standing on a sidewalk next to a jack hammer tearing up concrete.

Even if you plan for 115 dB peaks, which is extremely loud, you only need about 1.7 Vrms which is 0.048 watts. The O2 can provide 5+ Vrms which is good for 124 dB SPL with the LCD-2. And that's running from battery power.

So just on batteries alone the O2 will dirve the LCD2's to their limits and ear damaging levels.

 

There is not shortage of bass with the O2....if its there in the recording it will get amplified and if your cans can reproduce these low frequencies you will hear them!

 

Alex

When you listen to complex music with the LCD-2s, do you get compression? Whether or not an amp can drive a pair of headphones capably isn't just about the numbers, it has to be able to maintain a linear flow of power to the circuit despite the widely fluctuating voltage it has to deliver.

Quote:

Originally Posted by mikeaj 

Is there any laptop that seriously uses an adapter with AC output?  Why waste space and weight doing AC/DC conversion inside the laptop?  All the internal components run off of various levels of DC (so there are DC-DC step-down converters), and you want DC to charge the battery anyway.  Desktop computer ATX / BTX / whatever spec are all DC power.

 

 

 

If you're getting (buying) a new AC adapter, you may as well spend a few dollars extra on the beefed-up part, WA16-1000:

http://www.mouser.com/ProductDetail/Triad-Magnetics/WAU16-1000/?qs=sGAEpiMZZMtpkqKkT5w3uqH3NkAtJ%252bfiB%252bEoemwjDP0%3d

 

That's way overkill, but default WAU12-200 is a bit marginal if charging the batteries and running high power outputs.  It's probably plenty okay for most uses, which is why it's default, but it's just to save a few bucks.

Hey Mike,

For mainly using the O2 plugged in (with batteries installed) the WAU16 is a better option down the road?

Quote:

Originally Posted by Currawong 

 

When you listen to complex music with the LCD-2s, do you get compression? Whether or not an amp can drive a pair of headphones capably isn't just about the numbers, it has to be able to maintain a linear flow of power to the circuit despite the widely fluctuating voltage it has to deliver.

The one who designed the amp possibly knows more about audio and electronics than all people discussing here on head-fi together... Technical excellence of his amp has even been proved on innerfidelity. So if he claims (on his blog) that the amp is more than suitable for LCD-2, I would definitely trust him. Definitely.

However, one should be careful when using batteries... there could be clipping under certain conditions. More info is available on his blog, of course. And that's what I like - you can get all the info you need in order to drive your headphones with near-to-100% confidence.

Quote:

Originally Posted by HeatFan12 

 

Hey Mike,

 

For mainly using the O2 plugged in (with batteries installed) the WAU16 is a better option down the road?

WAU12-200 should be suitable unless you are going to use them with low impedance headphones, or phones that need a lot of current... Generally speaking. There are other conditions which require better transformer - for example sine wave testing...

You will be absolutely safe with WAU16-400 or WAU16-1000... I personally recommend 14-16V and 500+ mA to be 100% sure.

Quote:

Originally Posted by RustA 

 

WAU12-200 should be suitable unless you are going to use them with low impedance headphones, or phones that need a lot of current... Generally speaking. There are other conditions which require better transformer - for example sine wave testing...

 

You will be absolutely safe with WAU16-400 or WAU16-1000... I personally recommend 14-16V and 500+ mA to be 100% sure.

Thanks RustA,

Been using the O2 mostly with Ultrasones and Denon, so definitely an investment worth making.  Both are about the same price, so your recommendation 400 or 1000?

Quote:

Originally Posted by HeatFan12 

 

 

Thanks RustA,

 

Been using the O2 mostly with Ultrasones and Denon, so definitely an investment worth making.  Both are about the same price, so your recommendation 400 or 1000?

To be 1000% sure => 1000 mA... So WAU16-1000.

Quote:

Originally Posted by randomkid 

Mine is 15v 500ma thinking that's pretty safe

Yes... Mine is 15v 650ma though!

Quote:

Originally Posted by RustA 

WAU12-200 should be suitable unless you are going to use them with low impedance headphones, or phones that need a lot of current... Generally speaking. There are other conditions which require better transformer - for example sine wave testing...

 

You will be absolutely safe with WAU16-400 or WAU16-1000... I personally recommend 14-16V and 500+ mA to be 100% sure.

I know absolutely nothing about AC chargers and the correct voltages and current for gear. T_T

JDS Labs is going to send me a stock O2 charger (WAU12-200) free of charge since mine apparently died somehow. I use a 32-ohm V-MODA M-100, Shure SRH940, and 64-ohm AKG K 701 with my O2...as well a 16-ohm Sennheiser CX300 and MEElectronics M9 on occasion (I probably don't even need the O2 for those). Is the stock charger OK for my case, or do you think a different one would be more suitable?

Quote:

Originally Posted by miceblue 

I know absolutely nothing about AC chargers and the correct voltages and current for gear. T_T

 

JDS Labs is going to send me a stock O2 charger (WAU12-200) free of charge since mine apparently died somehow. I use a 32-ohm V-MODA M-100, Shure SRH940, and 64-ohm AKG K 701 with my O2...as well a 16-ohm Sennheiser CX300 and MEElectronics M9 on occasion (I probably don't even need the O2 for those). Is the stock charger OK for my case, or do you think a different one would be more suitable?

I would definitely consider a better one, especially for K701... As I said above, get something like WAU16-400 or WAU16-1000, or anything with 14-16V and 500+ mA at best.

It's not that you are going to experience BETTER sound but you will not get clipping or partial distortion even at the worst cases. For common usage, you are most likely not going to experience a difference - that's why JDS labs offer WAU12-200. I personally tried both WAU12-200 and WAU16-400 and they "sounded" the same to me, completely. So it's more about mitigating any possible problem that could occur.