[thread]

I recently picked up the Ultra Micro Amp to pair with my Ultra Micro DAC thinking it would be a good synergy. It's a totally decent sounding amp, but only if you're using headphones that are less sensitive.

When I plug my Shure SE530's or UE11's into this amp, there is quite a noticeable hiss. This noise floor would drive me crazy in silences and during quiet passages, so this amp is going back to HeadRoom.

I can even hear a faint hiss when using my full-size Edition 9 headphones!

The part that really annoyed me was that HeadRoom thinks that they can advertise this amp as a good companion to the SE530's! One of the images on their product page shows these together, and I think they should remove it.

I'm sure HeadRoom is a good company and all, generally speaking, but I really felt the need to share my experience on this one.

I guess Ray Samuels has spoiled me with his pitch black backgrounds.

Addition/Disclaimer: I need to add that I have done work for Ray, so I'm probably biased. Especially since his amps are the ones I've heard, mostly. However, I really didn't even consider this fact when I was writing my opinions in this thread. I just wanted to share my experience on this one as I was surprised with my result, and thought it warranted mentioning.

 

[billybob_jcv]

I can't help but notice that you also didn't mention the hiss problem in your ad for the Micro Amp...

"Up for sale is my virtually brand new Ultra Micro Amp from HeadRoom. It is in perfect condition. I've just decided this is not the amp for me."

 

[mackman]

I'm using a fairly sensitive pair of Denon 5000s with my Ultra Micro Amp/DAC and I only get hiss if I stop playing music, turn the gain to high, and the volume to about 50%. And normally I listen with the gain on low and the volume at about 10%, so the noise floor is probably 100 times quieter than I could hear at normal listening levels. I've used both USB and optical without any problem. So it sounds like you have a problem with your setup. I'd check your interconnect and look into getting a power filter.

 

[thread]

I have no reason to believe that there is anything wrong with my amp. I actually spoke to someone at HeadRoom about this, and they admitted that this can be an issue with very sensitive phones such as IEMs.

It is really almost inaudible with my Edition 9's (which are fairly sensitive as full-sized headphones go)... but there is a hiss.

(And I've come to this conclusion at home and at work. Don't these power supplies filter a lot of the noise? ... I really wouldn't think it's a power issue.)

None of Ray's amps that I've tried have any noise floor at reasonable listening volumes.

Edit: I've just fixed the subject from "...Hisses Bad Through IEMs" to just "...Hisses Through IEMs". I admit, that may have been an exaggeration as the hiss is not a total universally deal-breaking hiss. But it is definitely enough for me to not get too comfortable with this device.

 

[tot]

Quote:

Originally Posted by thread /img/forum/go_quote.gif It is really almost inaudible with my Edition 9's (which are fairly sensitive as full-sized headphones go)... but there is a hiss.

Hmm, I don't hear any hiss with Edition 9 from Ultra DAC/Amp combo. I have to put higher gain and max the volume to hear it.

 

[thread]

tot,

It is virtually inaudible. I have to listen closely to perfect silence, then remove the plug and hear slightly quieter silence.

I intended to use this amp for my IEMs.

 

[tot]

I tested again, and maybe it is not totally black even at normal low gain. But before I would classify it as a hiss, I need to go at least to medium gain and up the volume.

I agree they hiss with SE530's.

 

[thread]

I misspoke. There are TWO images of this amp with the SE530's. (There's only one with the HD650's!) Yeah, HeadRoom. Great pair!

 

[moogoob]

Hmm. Maybe you should post about this in the Headroom sponsor forum and get Tyll's input on the subject? I'd be interested to hear it.

My Micro amp sounds great with Grado 325is, but even I can hear slight hiss with no music playing if I up the gain to high (which if music WERE playing would probably blow out the drivers of my Grados) . My new Pro-ject Phono box on the other hand hums like mad at even moderate volume if nothing is playing, but I'd be willing to blame that on the cartridge (new but not too good), tonearm(30 years old!) or deck (same age as tonearm).

 

[MD1032]

I would bring this up with headroom. Those guys are really anal about that kind of stuff and I've never heard the kind of thing you're describing from any of their products. Try a different source also. I know my laptop sound card hisses really audibly.

 

[orkney]

Quote:

Originally Posted by moogoob /img/forum/go_quote.gif Hmm. Maybe you should post about this in the Headroom sponsor forum and get Tyll's input on the subject?

That's what I'd do. I have two HR amps at the moment and both are dead quiet with all my phones, including (basic) IEMs. Evan at full volume and highest gain through RS1s I hear only the faintest hiss. No way I'd notice it at any volume setting short of catastrophichearingdamage o' clock. They'll make it good.

o

 

[Bubu1]

This is my first post here. I've been reading the posts here at head-fi for a while and have learned a great deal and I want to thank all the headfiers for great dialogue. I was also wondering about the hiss. I also have the Headroom ultra stack (purchased in October) with the SE530's and even with the volume turned all the way down there is a noticeable hiss. I am currently using optical on the DAC and a cablepro panorama as my interconnect and the astrodyne power supplies. The hiss also does not seem to diminish when I plug the stack into my Furman AC-215 power conditioner. I love the sound of this setup but when listening carefully late at night (mostly classical) the hiss can get a bit annoying. Is it simply current running through the amp?
Many thanks,
Tom

 

[thread]

Yeah, the hiss I'm hearing can be heard with the volume at 0, with no sources connected at all.

It's unfortunate.

I've posted to the HeadRoom forum, asking someone to comment officially on this for us.

http://www.head-fi.org/forums/f77/ul...p-hiss-387717/

 

[thread]

HeadRoom's Mike Olson has weighed in on this with me via email:

Quote:

I don't think showing the Micro's with the 530's is misleading at all. I think they they are a great combo even if there may be the SLIGHTEST audible hiss in the background. To be honest this was the first time someone has brought this up and we've been selling the 530's and Micro's for years now. The hiss is so very slight so most people don't even hear it, especially while playing music. Most people love listening to their 530's directly out of an iPod and that hisses like hell. I personally own a pair of 530's and of course I've always noticed the slightest of hiss when using them, I just never let it bother me I guess. I don't know what else to tell you other than it's simply the 530's being what they are.

I guess we agree to disagree here. The hiss certainly might not drive every user batty, but I feel a "SLIGHTEST audible hiss" should be at least semi-difficult to hear in silence. With no source connected, gain at low, and volume at 0, the hiss is blatantly obvious to me. Quiet passages are tainted IMO... In fact, I might actually listen to music at a slightly higher level than the hiss. Obviously, though, it doesn't bother a great number of people. YMMV.

As of today, though, this amp has left my possession. I've replaced it with a second-hand SR-71A which has a pitch black background and what seems to be an even more engaging presentation. All things considered, I am thrilled with my Ultra Micro DAC / SR-71A combo. It's a real shame this amp is no longer available.

 

[Tyll Hertsens]

Quote:

Originally Posted by thread /img/forum/go_quote.gif With no source connected,

That's a bad way to test something. The input should be terminated.

Quote:

Originally Posted by thread As of today, though, this amp has left my possession.

Sorry we couldn't test it properly for you.