[Seifer01]

Hi,
 
I was thinking about buying a cheap integrated amp to use as a temporary headphone amp. I also want to use it with speakers in the future. I would be using it with my Marantz CDP. My questions are this;
 
1. Can an integrated amp be used without speakers wired up, just solely with headphones? (I've heard mention of integrated amps smoking and overheating, etc. when speakers aren't attached, but maybe that was the 70's or something, old amps and stuff).
 
2. The amp's headphone out says 250 mV into 32 ohms. Is that powerful enough to drive beyer dt 990 (250 ohms) ?
 
3. What is the difference between mV and mW?
 
Any help would be appreciated, thanks.

 

[jodgey4]

Mv can be used to calculate power. In this case, it would be Power=Volts^2 / Impedance, or (.25^2)/32 = 0.001953 W.

However, these numbers can't really help us determine power into your cans, because most speaker amps with headphone jacks just use a network of resistors from the speaker output, raising the output impedance of the output. That could actually mean more power than expected into your cans, luckily the high impedance of the Beyers will help mitigate usually resultant damping issues.

So, yes, it should work pretty well.

 

[Seifer01]

Mv can be used to calculate power. In this case, it would be Power=Volts^2 / Impedance, or (.25^2)/32 = 0.001953 W.

However, these numbers can't really help us determine power into your cans, because most speaker amps with headphone jacks just use a network of resistors from the speaker output, raising the output impedance of the output. That could actually mean more power than expected into your cans, and the high impedance of the Beyers will help mitigate damping issues.

So, yes, it should work pretty well.

Hi, thanks for your reply.
My beyers have a power handling capacity 100 mW, seems kind of low, although I have no idea about that kind of stuff. Numbers and calculations aren't my strong point.
 
As long as it works well, then I'll be happy.

 

[ProtegeManiac]

 
1. Can an integrated amp be used without speakers wired up, just solely with headphones? (I've heard mention of integrated amps smoking and overheating, etc. when speakers aren't attached, but maybe that was the 70's or something, old amps and stuff).

 
There shouldn't be any problem, anyway you can probably feel if the chassis is getting too hot. Unless you're touching a vacuum tube it's never supposed to be anywhere near scalding.
 

 
2. The amp's headphone out says 250 mV into 32 ohms. Is that powerful enough to drive beyer dt 990 (250 ohms) ?

 
Too many other variables. For one, headphone impedances vary greatly and so do amp output graphs. You can have an OTL amp for example that makes more power at 300ohms than at 32ohms. Then there's how loud is loud enough (without distortion) for you.
 

 
3. What is the difference between mV and mW?

 
Answers should be in one of the links on this page.
 

 
I was thinking about buying a cheap integrated amp to use as a temporary headphone amp. I also want to use it with speakers in the future. I would be using it with my Marantz CDP.

 
What Marantz CDP is that? I had a CD60 before and it can drive my HD600 well enough. I liked it better than the too-warm (and obviously colored) Little Dot MkII (connected to the line out on the CD60).

 

[Seifer01]

   
There shouldn't be any problem, anyway you can probably feel if the chassis is getting too hot. Unless you're touching a vacuum tube it's never supposed to be anywhere near scalding.
 
 
Too many other variables. For one, headphone impedances vary greatly and so do amp output graphs. You can have an OTL amp for example that makes more power at 300ohms than at 32ohms. Then there's how loud is loud enough (without distortion) for you.
 
 
Answers should be in one of the links on this page.
 
 
What Marantz CDP is that? I had a CD60 before and it can drive my HD600 well enough. I liked it better than the too-warm (and obviously colored) Little Dot MkII (connected to the line out on the CD60).

Thanks for the link and your advice. I'll probably ditch the idea of a cheap stop-gap integrated amp. I might just go straight for a Schiit Magni 2 Uber, it would cost a bit less than the amp I was looking at as well, and probably sound a lot better.
 
My CDP is just a CD 5004, the absolute bottom rung in the Marantz CDP range! although it's been replaced by the CD 5005 recently which has a more powerful headphone jack (28 mW/32 ohms. The 5004 only has 18 mW/32 ohms) So the headphone jack is pretty decent with my 32 ohm Senn's, but is a bit useless with my 250 ohm Beyers. I had a CD 63se, but that went to CDP heaven a couple of years ago! It was a  nice player as well.

 

[ProtegeManiac]

  Thanks for the link and your advice. I'll probably ditch the idea of a cheap stop-gap integrated amp. I might just go straight for a Schiit Magni 2 Uber, it would cost a bit less than the amp I was looking at as well, and probably sound a lot better.
 
My CDP is just a CD 5004, the absolute bottom rung in the Marantz CDP range! although it's been replaced by the CD 5005 recently which has a more powerful headphone jack (28 mW/32 ohms. The 5004 only has 18 mW/32 ohms) So the headphone jack is pretty decent with my 32 ohm Senn's, but is a bit useless with my 250 ohm Beyers. I had a CD 63se, but that went to CDP heaven a couple of years ago! It was a  nice player as well.

 
If you have a big enough equipment rack, what I would do is get a Schiit Asgard2 (I'm jut biased for full Class A; otherwise, the Magni2 looks like a great amp) and then just buy a used power amp for the speakers instead of getting an integrated amp (and then running the headphone out through its loop output). You're likely to find a very powerful power amp on eBay for a lot less money than many integrated amps, and you can use the preamp output on the headphone amplifier to control the volume on the speakers as well.

 

[guitargonaut]

Another option is the Vinyl Flat Can Opener.  It can be found here ==> http://www.vinylflat.com/canopener.html.
 
I liked my first one so much I bought a second for my work system.

 

[ProtegeManiac]

 

  Another option is the Vinyl Flat Can Opener.  It can be found here ==> http://www.vinylflat.com/canopener.html.
 
I liked my first one so much I bought a second for my work system.

 
I assumed he'd probably want the convenience of being able to switch between speakers and headphones without switching out speaker cables.
 

  I also want to use it with speakers in the future.

 

[Seifer01]

Yeah ease of use is a priority. I just want a nice setup that I can easily switch between speaker listening and headphone listening. Right now I'm concentrating on the headphone part of it.
 
I know someone with a pretty good setup, Nad stuff, pre amp, power amp, etc, Marantz CDP, Mordaunt Short floorstanders. The funny thing is he hardly ever gets to fire it up because of the people he lives with!
 
Anyway, thanks for your help people. The speaker setup shall go on the back burner for the time being. I'll be adding a decent turntable eventually as well. I haven't heard vinyl for about 25 years, it's time to revisit the spinning black circles of warmth

 

[jodgey4]

   
I assumed he'd probably want the convenience of being able to switch between speakers and headphones without switching out speaker cables.
 

Just use the A terminals for speakers and B for the Can Opener in that case.

 

[Mr Rick]

  Yeah ease of use is a priority. I just want a nice setup that I can easily switch between speaker listening and headphone listening. Right now I'm concentrating on the headphone part of it.
 
I know someone with a pretty good setup, Nad stuff, pre amp, power amp, etc, Marantz CDP, Mordaunt Short floorstanders. The funny thing is he hardly ever gets to fire it up because of the people he lives with!
 
Anyway, thanks for your help people. The speaker setup shall go on the back burner for the time being. I'll be adding a decent turntable eventually as well. I haven't heard vinyl for about 25 years, it's time to revisit the spinning black circles of warmth

When you are ready Schiit makes a phono preamp for you. Just sayin'