[thrice]

Quote:

Originally Posted by royewest /img/forum/go_quote.gif I built the "high performance" option. I can't turn the volume knob more than 30 degrees clockwise before the volume in my Senn 650s is way too loud to be comfortable.

What gain did you use? If you built it with a high gain, that would explain the lack of headroom with any headphone. If it's a gain of 11 then that would be more than enough to have that effect on even high impedance headphones.

Again, the high performance, or extended runtime versions are not the issue, it's the gain.

 

[holland]

Not only that, but the level of the source plays in this as well. What source are you using and what's the output voltage of it at full tilt (playing a 0dbFS file, for instance)?

One of my sources puts out about 3.5Vrms. With the Senns, and a gain of 5, I think I went till the volume was around the 9 o'clock position...which may be about 30 degrees.

 

[TheNew007]

hey guys, i have another question,
When I connect the source to the amp, what volume settings should I set on the source (eg, max, med, low).
Btw, thanks for all of the informative posts.

 

[FallenAngel]

Quote:

Originally Posted by TheNew007 /img/forum/go_quote.gif hey guys, i have another question, When I connect the source to the amp, what volume settings should I set on the source (eg, max, med, low). Btw, thanks for all of the informative posts.

You should be using the line-out (meaning no adjustable volume settings), if you have a source without a lineout, I'd say 80% volume to try to get a good balance of full volume without distortion.

 

[TheNew007]

I actually am using the lineout of the indigo echo dj but somehow I'm still able to change the volume using the speaker icon in the taskbar, but not via the volume controller on the card itself (which works fine for the other output).

 

[Kabeer]

Quote:

Originally Posted by royewest /img/forum/go_quote.gif After just a couple short listens (iPod headphone jack at max volume out, Apple Lossless, Lorraine Hunt Lieberman's heart schwimming in blood, cheap mini-mini cable, Mini3, Senn 650s), I'm delighted with the sound.

Royewest,
I dont know how you managed to get a good sound like this without bad clipping. But you should really be using your iPod's Lineout, NOT the headphone out.

Try it, you should get Much better results.

 

[amb]

Quote:

Originally Posted by TheNew007 /img/forum/go_quote.gif I actually am using the lineout of the indigo echo dj but somehow I'm still able to change the volume using the speaker icon in the taskbar, but not via the volume controller on the card itself (which works fine for the other output).

The volume control in the taskbar is probably doing the work in software by munging the audio data. If that's the case, you'd be better off setting it to maximum so that you don't lose digital resolution.

 

[royewest]

Quote:

Originally Posted by Kabeer /img/forum/go_quote.gif Royewest, I dont know how you managed to get a good sound like this without bad clipping. But you should really be using your iPod's Lineout, NOT the headphone out. Try it, you should get Much better results.

I just tried a SendStation LOD via mini plug.

If my volume knob starts at 7 o'clock at off and I turn it clockwise to turn on the mini3 amp, I can't listen at a volume higher than 11 o'clock, maybe 12.

I will search the mini3 build forums for clues on whether this is a build error of some kind.

I have now built two of these that exhibit the same volume -- but hey, no complaints! They are just super : )

 

[Kabeer]

Royewest, as for the volume..erm.. you might know more than me. But there are two versions of the Mini3. One is a low gain/high current version.
If you cant turn more than a bit using HD650's, then you most likely built a high gain version (im guessing).

 

[royewest]

A friendly head-wizer figured it out for me: There is a table of resistor values that set the gain of the amp to different multiples. I built the default "5x" gain version and forgot about the table entirely until reminded just now.

I just ordered a bunch more resistors to experiment with changing the gain to a 2x or 3x setting, so I have a bit more play on the volume pot.

 

[LouLanooch]

Will the high performance version drive 600 ohms?  More specifically I'm interested in the Beyer DT 770 600 ohm version (if anyone has firsthand knowledge)...

 

[FallenAngel]

I don't think you'll put a lot of voltage from a 9V battery into 600 Ohm headphones.  They're generally not meant to be used with portable amps.  Both "versions" (opamp combinations) are rail-rail opamps and 600 Ohms won't need a lot of current.  You'll simply run out of voltage before the amp clips with those headphones at reasonable volume.

 

[LouLanooch]

Would the 250 ohm version be a suitable compromise to pair with the mini3?

 

[FallenAngel]

Should be reasonable.