oldson
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Post by oldson on Dec 14, 2015 21:28:38 GMT
I'm having a little problem with low level hiss and hum, because I use the Ember at work with a lot of noisy sources messing up and its getting a bit annoying. That's why I think I'll move the Ember back home, and use something like the Polaris at work. None of my headphones are high impedance, but I've read that the Fostex need some power to not sound too flabby in the bass area. The Polaris might be a much better partner to it than the Ember. Well....have to wait until Christmas has passed before spending more on this wonderful hobby, and these wonderful products from Garage 1217:-) have you tried using an impedance adaptor? |
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Rabbit
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Post by Rabbit on Dec 14, 2015 21:32:02 GMT
I'm looking for another amp to complement my Ember II, and I'm searching for a solid state amp. I'm feeling that Polaris might be a very good choice. After reading in this thread and the Polaris thread it's difficult to pinpoint clear differences in quality between this and the Ember. Can anyone shed some more/clearer light on this matter? The other amp I'm curios about is the Grace Design m9xx with dac(don't really need dac), and is also almost double the price of the Polaris. It looks like my main headphone will be the Fostex TH-x00 for a while, and that's a 25ohm load. Maybe the Polaris will be a better choice for this headphone cop mpared to the Ember? Hi, give a read here, I compared them extensively. Maybe it can helps. I imagine that hiss wouldn't be airborn. That'll be the lower impedance headphones. One way to help it is to just look for a quieter tube. Buzzes are another thing. You would get less noise from the Polaris. The Fostex needs a nice healthy current rather than big voltage to get the driver under control in the bass region. One amp I really like with it is a battery operated Ifi Micro idsd. It really gets a grip. Not cheap though. It's better as a digital amp but not as bad as many might have you believe as a normal amp. Mine gets used in all kinds of situations, including digital audio from the TV. Then you get no interference from the to itself and free view radio in the UK, sounds pretty good as a result. |
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Post by tommo21 on Dec 15, 2015 6:13:36 GMT
Hi, give a read here, I compared them extensively. Maybe it can helps. I imagine that hiss wouldn't be airborn. That'll be the lower impedance headphones. One way to help it is to just look for a quieter tube. Buzzes are another thing. You would get less noise from the Polaris. The Fostex needs a nice healthy current rather than big voltage to get the driver under control in the bass region. One amp I really like with it is a battery operated Ifi Micro idsd. It really gets a grip. Not cheap though. It's better as a digital amp but not as bad as many might have you believe as a normal amp. Mine gets used in all kinds of situations, including digital audio from the TV. Then you get no interference from the to itself and free view radio in the UK, sounds pretty good as a result. Yeah, it's very tube dependent. I have very little noise with my 6j5 Visseaux tubes at the moment. Also very little noise with most tubes in the 6v family. I can't use 12ax7 tubes and also 7193 tubes are out of the question here at work. The headphones I use most at the moment is the Audio Technica MSR7 which have been measured at around 38ohm. It's a bit funny because if I move my hand closer from the left side of the tube, the high pitched hissing stops. When I hold my hand over the tubes it starts buzzing more on the tubes that buzz. Not touching...just 4-5 cm/2 inches away. |
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Rabbit
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Post by Rabbit on Dec 15, 2015 7:39:50 GMT
I've never tried that!!
I always find amp noises quite distracting so for me, matching can be an issue. 38 ohms is quite low for an Ember. (Or any tube amp) It will pick up noises very easily. One of the reasons why some pros like 600 ohms is noise rejection, along with the idea of sharing outputs.
To be honest, to get the best out of the Ember, imp it is better to have higher impedance headphones attached.
You could try what Oldson suggested. Add an adapter, but this 'might' alter the sound slightly since it raises the output impedance of the amp. It could slightly raise the bass or make the treble less prominent.
I certainly find the impedance of the th900 a bit too low for the Ember and use the Polaris with it.
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howie
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Post by howie on Dec 15, 2015 14:48:55 GMT
I hate hiss too. I tried one of those adapters Ian, I think 75ohm resistance, and, as you say, it differentially affected the frequencies. The sound was so weird I thought my amp had broken. The orchestra sounded like they were drunk.
What I do now is I use a variable in line resistor, made by Sennheiser as an extension cable/vol control, and with this you can just very slightly move the slider until the hiss goes away and it rarely needs to be moved to the point the sound is affected, other than the volume of course, which can be compensated for at the amp. There is an added advantage that you can alter each channel separately so it acts as a balance control too should you need one. It gets rid of hum in the same way but usually with greater adjustment needed. Not ideal but better than nothing.
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Post by tommo21 on Dec 15, 2015 15:10:27 GMT
I hate hiss too. I tried one of those adapters Ian, I think 75ohm resistance, and, as you say, it differentially affected the frequencies. The sound was so weird I thought my amp had broken. The orchestra sounded like they were drunk. What I do now is I use a variable in line resistor, made by Sennheiser as an extension cable/vol control, and with this you can just very slightly move the slider until the hiss goes away and it rarely needs to be moved to the point the sound is affected, other than the volume of course, which can be compensated for at the amp. There is an added advantage that you can alter each channel separately so it acts as a balance control too should you need one. It gets rid of hum in the same way but usually with greater adjustment needed. Not ideal but better than nothing. Would this do the job as well? Shure EAADPT-KITOr the deluxe version: SES |
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howie
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Post by howie on Dec 15, 2015 16:05:28 GMT
That's the idea. This is the one I use: www.amazon.co.uk/Sennheiser-HZR62-Stereo-Volume-Control/dp/B000H0K8VYThe chord is far too long for me so I cut it and re-terminated with a 6.3mm Jack. There was some discussion on the Forums about these recently but I can't find it. Another method was suggested but when I tried to purchase the item it was no longer for sale. If I find the link I'll post it. If you can get rid of the noises by just increasing the output impedance on the amp that would be easier for you to do but you may find the sound unacceptably changes, albeit subtly. I find it tends to be less dynamic and clear, but just occasionally that's to the advantage of the recording. |
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Rabbit
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Post by Rabbit on Dec 15, 2015 16:31:44 GMT
Yes, it was me that brought it up before. I have one of the Shure types. Frans mentioned that it was changing the output impedance but as you say, because it's variable, you can adjust until the hiss has just gone.
You are also right, it kind of 'dulls' the sound if used flat out.
Best option is a quiet tube really. For me, the Polaris just works better with lower impedance headphones though because of the lower noise floor.
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Deleted
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Post by Deleted on Dec 15, 2015 16:37:20 GMT
I think I found the discussion you were referring to Howard. P114-115 of this very thread: diyah.boards.net/thread/143/project-ember?page=114Wasn't the easiest to find as the search function seems a bit hit & miss so ended up trawling through my post history. Not sure if it was the ifi adapter I have that you'd tried to buy or a different one? Frans also mentions quite a neat DIY option that lowers the output impedance. |
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howie
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Post by howie on Dec 15, 2015 17:00:27 GMT
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Deleted
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Post by Deleted on Dec 15, 2015 17:07:38 GMT
If you're still after one of the ifi adapters let me know and I'll send you mine. It's been sitting unused in my 'bits & bobs' cupboard since the Ember went and my O2 (had it built with 1x & 2.5x gain) gives me all the volume control I could ever need.
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howie
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Post by howie on Dec 15, 2015 17:11:25 GMT
Yes, it was me that brought it up before. I have one of the Shure types. Frans mentioned that it was changing the output impedance but as you say, because it's variable, you can adjust until the hiss has just gone. You are also right, it kind of 'dulls' the sound if used flat out. Best option is a quiet tube really. For me, the Polaris just works better with lower impedance headphones though because of the lower noise floor. Totally agree, Ian. I think it's good to be able to lower the output gain on the Polaris too, that helps. It's odd though that some lower impedance cans, say around 32 Ohms, hiss and others don't. I get the impression it may also have something to do with sensitivity and treble response as well. For instance my HE 400 never hisses in Horizon or Ember, and nor do my nice new modded Philips Uptowns. |
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Deleted
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Post by Deleted on Dec 15, 2015 17:18:41 GMT
I didn't find noise too much of an issue with my Denon MM400 either. They're 32 ohms too but relatively low sensitivity at 96dB.
The Pandora (used with very careful control of the volume knob!) hissed like a b***er with the same tube. But that's quite an extreme case I guess (8 ohms & 105dB).
When I had the Lyr I used to use the Denon D2000 with it (25 ohms & 106dB). Quite a high noise floor but I was willing to live with that because the pairing was gorgeous. Very organic and live sounding yet also very well controlled.
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howie
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Post by howie on Dec 15, 2015 17:20:09 GMT
That's very kind of you Mark but I think it seems okay now with the Sennheiser. Also, I've got used to using the channel balance control and not sure I could do without it now. It's amazing how you notice poorly balanced recordings once you can adjust for these things. It really p***es me off when a recording engineer can't place four quartet players in their proper positions with respect to the listener, like first violin is in the middle and the cello off at the far right side of the stage.
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Deleted
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Post by Deleted on Dec 15, 2015 17:26:03 GMT
That's not a problem Howard. The option to adjust the channel balance is something I'd find hard to give up too.
It's also a bugbear of mine when recordings seem lopsided....sometimes that's down to my hearing (think my left ear is slightly weaker than the right) but not always. Either way the option to tweak things to my liking would be very welcome!
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