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*Comparison and Review* Magni/Modi vs O2/ODAC - Page 17

post #241 of 440

I use thick Velcro, specifically something like this http://www.velcro.com/Products/Ties-and-Straps/Ties/One-Wrap-Tie-Rolls.aspx

I have a piece between the units, and a wrap around them. It's thick enough to basically be feet; keeps the O2 off the table and the ODAC from sliding on the O2. It can also be taken apart and the units separated without leaving any trace since it isn't adhesive.

 

You can see it in the background here (with a velcro-wrapped cable on top so I can carry it around):

 


Edited by trueserve - 1/18/13 at 9:54pm
post #242 of 440
Quote:
Originally Posted by trueserve View Post

I use thick Velcro, specifically something like this http://www.velcro.com/Products/Ties-and-Straps/Ties/One-Wrap-Tie-Rolls.aspx

I have a piece between the units, and a wrap around them. It's thick enough to basically be feet; keeps the O2 off the table and the ODAC from sliding on the O2. It can also be taken apart and the units separated without leaving any trace since it isn't adhesive.

 

You can see it in the background here (with a velcro-wrapped cable on top so I can carry it around):

 

Woah that's pretty clever. I might give that a try instead!

post #243 of 440
Quote:
Originally Posted by miceblue View Post

Woah that's pretty clever. I might give that a try instead!

Check out the Velcro One Wrap Straps that have the hole at the end to run the strap through:

http://www.amazon.com/Velcro-Wrap-Strap-2-Inches-Pack/dp/B0057564NK/

Those are a little long at 15", but you can trip then end down.
post #244 of 440
Quote:
Originally Posted by Jason Stoddard View Post

It's simply the quiescent current in the output stage--in the case of Magni, about 30mA--hardly enough to really get warm. P= IV, where I is .03 and V is 30V--so it dissipates about 2W at idle from 2 channels. I forgot the actual FLIR numbers, but it runs something like 27C in a 20C room.

 

Don't forget the regulators. biggrin.gif

 

After a 30 minute warmup (and measuring immediately after removing the top cover), the regulator cases were running around 140F (60C) and the output devices around 150F (66C). That's enough to make the top cover feel warm, but certainly not hot.

 

Top cover with Magni off was 72F. After idling for about 30 minutes, it rose to about 84F. Warm to the touch, but not even body temperature. So no reason for anybody to fret.

 

Oh yeah, while you're here, my Magni has a problem. Whenever I turn the knob all the way to the left, I get no sound. What's up with that? Can I get a new one? tongue.gif

 

Have a great weekend, Jason!

 

se

post #245 of 440
Quote:
Originally Posted by TheGame21x View Post

I'm pretty sure he was serious. confused_face(1).gif

 

put a rubber band on the RCA cables connecting the Magni and Modi and they should sit flat. Worked for me.

I should have said around the cables sorry.

post #246 of 440

Steve,

 

Just flip it upside down...it will fix the problem....

 

Alex

post #247 of 440

Tried that. Still get no sound when the knob's turned all the way to the left.

 

se

post #248 of 440
Thread Starter 

Make sure that when it's turned upside down that the power switch in the back is down instead of up.

post #249 of 440
Quote:
Originally Posted by Steve Eddy View Post

Oh yeah, while you're here, my Magni has a problem. Whenever I turn the knob all the way to the left, I get no sound. What's up with that? Can I get a new one? tongue.gif

 

se

 

Yeah, I've heard of that problem. About 99.8% of the Magnis have it, unfortunately. I've heard it's a relatively common problem with other amps.

 

Despite that, we'll put our entire engineering team on it and see if we can develop a fix. I believe Dave (our DSP and microcontroller wizard) could probably work up a PIC-based control system that would, say, allow you to get full volume at the touch of a button even with the pot fully to the left. Of course, that may not be the best solution, unless you want a special "destroy my headphones" function.

 

(Actually, the first preamp I designed for Sumo had the pot wired backwards on the prototype PCBs. So, in that case, you'd have plenty of output at full left, especially with 20dB gain and +/-35V rails. Hello, voice coils.)

post #250 of 440
Quote:
Originally Posted by Jason Stoddard View Post

 

Yeah, I've heard of that problem. About 99.8% of the Magnis have it, unfortunately. I've heard it's a relatively common problem with other amps.

 

Despite that, we'll put our entire engineering team on it and see if we can develop a fix. I believe Dave (our DSP and microcontroller wizard) could probably work up a PIC-based control system that would, say, allow you to get full volume at the touch of a button even with the pot fully to the left. Of course, that may not be the best solution, unless you want a special "destroy my headphones" function.

 

Not to worry. I just took it out to the shop and monkeyed around with it for a bit. Got it working perfect now. 

 

 

 

Quote:

 

(Actually, the first preamp I designed for Sumo had the pot wired backwards on the prototype PCBs. So, in that case, you'd have plenty of output at full left, especially with 20dB gain and +/-35V rails. Hello, voice coils.)

 

Did something similar to that myself once. Was picking bits of wire and polypropylene out of my teeth for a week. Oops. redface.gif

 

se

post #251 of 440

I love it! The alternate-universe Magni...

post #252 of 440

I'll send it on down. Wait'll you experience the alternate reality it produces.

 

 

se

post #253 of 440
Quote:
Originally Posted by Steve Eddy View Post

Quote:
Originally Posted by Jason Stoddard View Post

It's simply the quiescent current in the output stage--in the case of Magni, about 30mA--hardly enough to really get warm. P= IV, where I is .03 and V is 30V--so it dissipates about 2W at idle from 2 channels. I forgot the actual FLIR numbers, but it runs something like 27C in a 20C room.

 

Don't forget the regulators. biggrin.gif

 

After a 30 minute warmup (and measuring immediately after removing the top cover), the regulator cases were running around 140F (60C) and the output devices around 150F (66C). That's enough to make the top cover feel warm, but certainly not hot.

 

Top cover with Magni off was 72F. After idling for about 30 minutes, it rose to about 84F. Warm to the touch, but not even body temperature. So no reason for anybody to fret.

 

Oh yeah, while you're here, my Magni has a problem. Whenever I turn the knob all the way to the left, I get no sound. What's up with that? Can I get a new one? tongue.gif

 

Have a great weekend, Jason!

 

se

Doesn't that happen with most amplifiers? Maybe not...my lack of experience is getting to me isn't it? XD

I always thought the volume knob is supposed to go from volume 0 to volume max.

post #254 of 440
Quote:
Originally Posted by Jason Stoddard View Post

 

Yeah, I've heard of that problem. About 99.8% of the Magnis have it, unfortunately. I've heard it's a relatively common problem with other amps.

 

Despite that, we'll put our entire engineering team on it and see if we can develop a fix. I believe Dave (our DSP and microcontroller wizard) could probably work up a PIC-based control system that would, say, allow you to get full volume at the touch of a button even with the pot fully to the left. Of course, that may not be the best solution, unless you want a special "destroy my headphones" function.

 

(Actually, the first preamp I designed for Sumo had the pot wired backwards on the prototype PCBs. So, in that case, you'd have plenty of output at full left, especially with 20dB gain and +/-35V rails. Hello, voice coils.)

Jason, I am proud to be your customer :D

post #255 of 440
Quote:
Originally Posted by Steve Eddy View Post

I'll send it on down. Wait'll you experience the alternate reality it produces.

 

 

se

 

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