Rabbit
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Post by Rabbit on Feb 16, 2015 18:43:29 GMT
I'm not sure Gordon. I think it might not go direct from dac because the order might be;
source > filter > amp > headphone. The Kameleon has it built in as a small card that you can change depending on the headphone. I really like the Kameleon as well.
The amp should supply a flat signal. Most do. Even the Ember. You're just hearing harmonics. The filter corrects headphone anomalies.
Having said that, a filtered HD650 doesn't sound exactly the same as a filtered DT990. I know the theory goes that flat is flat but there are other considerations to take into consideration such as cup enclosure size, ringing, speed of drivers etc.
They are modded to sound as flat as possible. They aren't solidly flat from top to bottom. Sharp peaks are smoothed and in the case of the Senn, the sub bass which is almost there in the first place is boosted so that it it much more apparent. That doesn't make the Senn more bassy. It just hits lower with more power. It kind of smoothes the headphone out with no real peaks to speak of.
The Senn is for me the best of the bunch. It's a very fast headphone and corrected, it's tonally extremely good. The amp supples the dynamics, and shouldn't supply a different timbre. Believe it or not, the Ember is very flat. Your headphone isn't!!
What is quite amazing is just how good the modded Philips headphone is at the price it sells at. It also goes very low and has a 'similarity' with the Senn! It's not as open but damned good .... No filter and straight from a dap.
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Deleted
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Post by Deleted on Feb 16, 2015 19:01:06 GMT
It wouldn't make sense if the filter was before the amp because those harmonics the valve produces would then be added to the already filtered signal, thus rendering - at least in part - the filter inaccurate. If the filter comes after the amp then that makes sense but would also mean the actual amp - as long as basic operational requirements (power, current etc) are met - would be irrelevant. At least to a degree. I am prepared to be proven completely clueless.  |
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Rabbit
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Post by Rabbit on Feb 16, 2015 19:11:19 GMT
Yes, that's where the valve 'flavour' is added for those that prefer it.
For some reason, I seem to think that the filter might go before the amp section. Frans will know for sure!!!! It might also keep noise down. The Kameleon is deathly quiet.
The harmonics don't change the frequency response of the amp. It is essentially flat in spite of what is written on HF about humps in the bass. It's the effect of the harmonics that gives the 'feeling' of added weight. In tubes, you get lots of even harmonics which kind of reinforces our impression of bass. The louder the amp goes, the more harmonic distortion you get as well. So the bass can appear to grow with volume.
Tubes (if you like) add distortion to the signal. They don't change the frequency response as much as you think. You 'perceive' more bass as a result of added distortions basically.
The Ember and Polaris measure flat and go very high too.
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Deleted
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Post by Deleted on Feb 16, 2015 19:35:41 GMT
The harmonics don't change the frequency response of the amp. It is essentially flat in spite of what is written on HF about humps in the bass. It's the effect of the harmonics that gives the 'feeling' of added weight. In tubes, you get lots of even harmonics which kind of reinforces our impression of bass. The louder the amp goes, the more harmonic distortion you get as well. So the bass can appear to grow with volume. Tubes (if you like) add distortion to the signal. They don't change the frequency response as much as you think. You 'perceive' more bass as a result of added distortions basically. I get it now. I was confusing frequency response with actual sound & obviously they are not necessarily the same thing. |
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Deleted
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Post by Deleted on Feb 16, 2015 19:42:55 GMT
The Polaris is not just a solid-state Ember as I've seen some say.
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Rabbit
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Post by Rabbit on Feb 16, 2015 19:48:19 GMT
If you look at the fr graphs of the Ember and Polaris, they're pretty flat and they go up a long way. Most amps nowadays are pretty flat really.
The harmonic content of the Ember is quite different to the Polaris though. Tubes produce a kind of distortion, which consists of even harmonics. To the ears, even harmonics don't sound anything like as nasty as odd harmonics and make music sound 'richer'. That's what people describe as a tube sound.
The Polaris imitates the production of even harmonics but it's not the same coming from transistors so it's just not as pronounced. Some prefer the tubey sound and others, the cleaner sound.
The biggest skew in frequency response comes from the headphones themselves. That's what the filter tries to compensate for by smoothing out peaks and even boosting extreme bass in the case of the Senn, which is already there, but much quieter down in the mix. After all, if a driver can't produce proper bass, boosting very low bass would just introduce nasty distortions. The Senn drivers are very good and work quite well down there. Many headphones don't get close.
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Rabbit
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Post by Rabbit on Feb 16, 2015 19:50:33 GMT
The Polaris is not just a solid-state Ember as I've seen some say. No, it's not. It emulates a tube response using ss. (Fets I think) it's not the same amount of even harmonic distortion which is why I instantly noticed that it was less tubey sounding than the Ember. Less harmonics I guess means less distortion!! |
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Deleted
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Post by Deleted on Feb 16, 2015 19:52:09 GMT
Yeah, I've looked at those graphs a lot actually, lol. I need to get out more.
The trouble is the cynical 21st century side of me wants to love the SS amp but the old romantic in me - and the realist too, it would seem - really likes the distorted sound of the valve.
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Rabbit
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Post by Rabbit on Feb 16, 2015 19:56:16 GMT
If it sounds good to you, then that's fine. I wouldn't worry about it personally. I like both for different reasons.
I know what you mean about head and heart with tubes. Go with the heart ..... That's where your real likes are. Same for me with headohones. I like flat as possible, with the exception of the bass which I prefer slightly raised. To me, it's more speaker like that way and so easier to listen to. It also compensates for the lack of physical vibration in the bass.
However, that's not flat is it? It's what I prefer. (Or flat with a tube amp is nice)
I always go from what I hear in the end. Measurements are fine but on the head is very important, no matter what figures say. Try a Philips headphone that has been modded and you'll start to wonder why we spend so much money on headphones!!! My head tells me it's a cheap headphone but my ears tell me that they sound really good. Doesn't mean I won't use them. I've been using them all day today. Cheap headphone that shouldn't really sound this good at that price!!!!!
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Deleted
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Post by Deleted on Feb 16, 2015 20:04:22 GMT
Tell me about it! My modded Sennheiser PX100II's sound superb. As good as the 650? No, but good enough & different enough to be valid. And £40! I'm warming to the Polaris actually. It sounds more accurate, as if I can hear into my music a bit more than with the Ember. I'm just not sure I feel it more. There are also practical reasons for wanting the Polaris to be better which I'm trying very hard to disregard.  |
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Deleted
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Post by Deleted on Feb 16, 2015 20:07:13 GMT
I apologize to everyone for hogging this thread.
The bandwidth settings, hmm. I've read the rationale behind it but I still don't really get it. What category of DAC would anyone say the ODAC belongs to? What does "NOS" mean when applied to a DAC?
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Rabbit
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Post by Rabbit on Feb 16, 2015 20:09:11 GMT
NOS stands for 'New, old stock'. In other words, antique but never used! Not sure how it applies to a DAC.
Tubes that we use tend to come from 60s and 70s but have never been used sometimes. Mind you, Ebay sellers often lie. How can you tell?
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Deleted
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Post by Deleted on Feb 16, 2015 20:12:54 GMT
That was my understanding too. I guess DAC's have been around for quite a while now really. We're just old.  |
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Javier
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Post by Javier on Feb 16, 2015 20:16:05 GMT
In DACs NOS = Non Over Sampling
Sent from my GT-I9100 using proboards
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Rabbit
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Post by Rabbit on Feb 16, 2015 20:18:48 GMT
Aha!!!! Thanks Javier.  |
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