[Audiophilic10]

They didn't say the tubes are there for show. The tubes are not used for real amplification, but used as buffer which color the sound possibly by introducing some distortion. The tubes have an effect on the sound as changing the tubes change the sound profile. What engineers call better, and what audiophiles call better may be two different things, as clinically accurate may not always sound the best. Sound is very subjective. I use this amp with the Sennheiser 6xx and it sounds quite satisfying, although in certain songs, I can hear some distortion/crackling at regular volume although such instances are very rare.

Hello sup27606,
yes, they didn't say tubes are for show (that would be having just a glowing tube doing nothing) but they elaborate that tubes were included into the design for the sake of having/showing tubes there... that's what I don't like so much. I don't want to diss the amp as for the price it seems a bargain and it's been stated to work, but were I to get a tube amp I'd prefer one built properly around tubes.

 

[joemg]

This is a hybrid amp, the amplification is made by pair op amp and valve. Other relatively cheap headphone amps with valves also are hybrid ones. Also, most of them are using triodes (pure ones). This one uses pentode as triode, but due to tube design, it gives reacher, more vivid sound.
Since I have Fiio E10K for a long time now, I made a direct comparison after a tube rolling. Everything is better, just everything, especially highs and extension and control of lows. And even after tube and op amp rolling (maybe I was lucky to buy valves really cheap) the total cost of 08E was less then Fiio's.

BTW, I needed a good amp for all fine hp range (32 Ohm up to 600 Ohm) with a plenty of power. Too many amps prised here actually can't drive 250 Ohm cans: they lack resolution and control. Not even counting for 600Ohm cans.

I'm genuinely curious about your findings:

When you compared the e10k and the 08e, were you using the dac on the e10k vs a different dac for the 08e or does the e10k give a line out? (Mine hasn't arrived yet)

I'm almost wondering if I should order both and just return the one I don't like as much... but then I'd need a dac too for the o8e...

 

[sup27606]

 
Hello sup27606,
yes, they didn't say tubes are for show (that would be having just a glowing tube doing nothing) but they elaborate that tubes were included into the design for the sake of having/showing tubes there... that's what I don't like so much. I don't want to diss the amp as for the price it seems a bargain and it's been stated to work, but were I to get a tube amp I'd prefer one built properly around tubes.

 
They are using the tubes for coloring the sound instead of using them directly for amplification. The main task of amplification is done by the op-amps. Thats what I understand from the video. What the presenter (and the specialist he consulted towards the end) was saying was that, including the tubes probably introduced more distortion than not including them, which is probably true. In a way, adding the tubes is probably superfluous to the design. However I like how changing the tubes changes the sound profile, for example from the stock ones to the Mullard 6688s. What I find problematic about the video is, there is not a single mention of actual sound quality besides all the technical talks. They also did not bypass the tubes and compared whether the sound is better or worse without the tubes. Also, there is a general contempt towards audiophiles (the presenter refers to them as audiofools at one point).
 
I am also not sure, how much I can emotionally connect with pure clinical sound. Is it even necessary for enjoying music? While listening to music through loudspeakers under practical conditions, or in a concert hall, there is always distortion present due to acoustics. Still such music is enjoyable.
 
BTW, after seeing your post, I was curious about the Bravo V1, so I went ahead and ordered one. These amps are supposed to use only the tube for amplification, without any ICs. I will post the comparison with the Nobsound once I listen to both.

 

[Audiophilic10]

I agree on all you say, it would've been good some talk about sound on their part. I look forward to your findings!

 

[LazyListener]

Does this amp benefit from burn in?  Has anyone noticed a change in sound over time?  Also, do the tubes require burn in or warming up to sound best?  If so, how long, and is it a one time thing or after each cool down and power up cycle?

 

[sup27606]

I don't know about the burn-in, but the tubes should be warmed up to the recommended 15 sec every time before plunging in the headphones. Otherwise there will be a sharp transient sound through the phones which is not pretty.

 

[LazyListener]

I don't know about the burn-in, but the tubes should be warmed up to the recommended 15 sec every time before plunging in the headphones. Otherwise there will be a sharp transient sound through the phones which is not pretty.

Thanks!  Where do you get the 15 sec recommendation from?  I didn't get a manual or any documentation with mine with any recommendations.  Is that just a thing for tubes in general?
 
I just got mine and I have to say I'm not too thrilled initially.  It's too bright sounding for my taste.  My Magni 2 sounds much more neutral and smooth.  I know I can buy other tubes to change the sound but was hoping I wouldn't have to.

 

[edulov]

I don't know about the burn-in, but the tubes should be warmed up to the recommended 15 sec every time before plunging in the headphones. Otherwise there will be a sharp transient sound through the phones which is not pretty.

Burn-in - no need, 20-30 sec for warming. I tried to catch the differences after extended warming (>3 mins) but on the edge of fooling myself. It looked that extended lows became slightly better controlled and full-bodied, but you need special test tracks and good cans. So if you are not a hardcore bass-head - just ignore or wait a couple of minutes.

 

[edulov]

For LazyListener:
Amp comes with cheap horrible vacuum tubes. ANY other is better. Just take into account that not all tubes provide really extended, "clean" lows if you want to hear bass where track comes with them. Just do not forget that you will need good cans to catch the difference. If yours will show signs of muddiness and became boomy at lows or on the contrary became too harsh at highs it is just the sign to get better headphones before fine tube rolling or even op amp switching.

 

[sup27606]

Thanks!  Where do you get the 15 sec recommendation from?  I didn't get a manual or any documentation with mine with any recommendations.  Is that just a thing for tubes in general?

I just got mine and I have to say I'm not too thrilled initially.  It's too bright sounding for my taste.  My Magni 2 sounds much more neutral and smooth.  I know I can buy other tubes to change the sound but was hoping I wouldn't have to.

Please see this link for the 15 sec recommendation:
http://www.doukaudio.com/Product/detail/id/7.html

Strange that you find it bright sounding. For me, it had warm sound with very deep lows and good soundstage. The stock tubes had poor treble response, so I replaced them with tubes as recommended in this forum. Now it sounds quite pleasant.

 

[sup27606]

Burn-in - no need, 20-30 sec for warming. I tried to catch the differences after extended warming (>3 mins) but on the edge of fooling myself. It looked that extended lows became slightly better controlled and full-bodied, but you need special test tracks and good cans. So if you are not a hardcore bass-head - just ignore or wait a couple of minutes.

It's an analog device, so I have no problem in believing what you are hearing. There may be some marginal improvements after extended warming. I think the 15 sec recommendation is based on the time when it approaches near optimal sound, like 95% of steady state sound or something. Also, is it possible that different tubes have different heating times?

 

[LazyListener]

Please see this link for the 15 sec recommendation:
http://www.doukaudio.com/Product/detail/id/7.html

Strange that you find it bright sounding. For me, it had warm sound with very deep lows and good soundstage. The stock tubes had poor treble response, so I replaced them with tubes as recommended in this forum. Now it sounds quite pleasant.

I think I'm sensitive to brightness.  It does sound warm down low with good bass, but too bright up top.  I agree, soundstage is pretty good, but some background sounds are a bit harder to hear than with other amps.
 
I just swapped from it to E10K, and I actually prefer the sound of the E10K.  More neutral and balanced sounding.  Bass isn't as pronounced.  Soundstage is just as good, if not better.  No issue with not being able to hear background sounds.
 
I'm using HD 650 for testing.
 
I will have to consider different tubes, but I really, really didn't want to get into swapping tubes right away.

 

[edulov]

To LazyListener:
 
Before going into the discussion I checked my FR database about HD650. It seems that there exist 2 completely different versions. One - you may call balanced and good, the other one has really bad lows and horrible treble. For me, it was a reason to ignore this cans. So w/o knowing which one is yours, a discussion is meaningless. Its Senn's fault, not yours.
 
1. Some call the sound bright not taking into consideration that DAC, amp, hp's or spk's are honest and that it a real track sound, how it was meant to be. Or mess up brightness with sibilance.
2. Since hp amp's soundstage is one of the cornerstones to differ between regular and better ones, I spent some time testing different tracks, amps and cans. My setup is times better then E10K. Also, this Fiio has one "undocumented" feature: quite bad THD at middle and especially high treble. Only after owning several good hp's I confirmed this instrumental measurement bu ear. But going back to soundstage: after tube rolling 08 offers not just a width, but depth and even slightly heights. I was really surprised how some tracks sounded afterwards being capable to locate instruments and vocals. At the same time I'd say 95% of tracks showed miserable width, no depth. SO bad tubes is the best choice to stay away from knowledge of being fooled. BUT! You'll need a really good set of open cans too hear that.
3. For the price Fiio E10K offers good lows, but tube rolling gave me extension, body and control. Actually after hearing some tracks after "tuning" I deleted them surprised how bad they sound at lows when you can really hear below 100 Hz.
 
PS. About Senn's. Some old school 4xx and 5xx open cans are much better than any of the 6xx series.

 

[LazyListener]

  To LazyListener:
 
Before going into the discussion I checked my FR database about HD650. It seems that there exist 2 completely different versions. One - you may call balanced and good, the other one has really bad lows and horrible treble. For me, it was a reason to ignore this cans. So w/o knowing which one is yours, a discussion is meaningless. Its Senn's fault, not yours.
 
1. Some call the sound bright not taking into consideration that DAC, amp, hp's or spk's are honest and that it a real track sound, how it was meant to be. Or mess up brightness with sibilance.
2. Since hp amp's soundstage is one of the cornerstones to differ between regular and better ones, I spent some time testing different tracks, amps and cans. My setup is times better then E10K. Also, this Fiio has one "undocumented" feature: quite bad THD at middle and especially high treble. Only after owning several good hp's I confirmed this instrumental measurement bu ear. But going back to soundstage: after tube rolling 08 offers not just a width, but depth and even slightly heights. I was really surprised how some tracks sounded afterwards being capable to locate instruments and vocals. At the same time I'd say 95% of tracks showed miserable width, no depth. SO bad tubes is the best choice to stay away from knowledge of being fooled. BUT! You'll need a really good set of open cans too hear that.
3. For the price Fiio E10K offers good lows, but tube rolling gave me extension, body and control. Actually after hearing some tracks after "tuning" I deleted them surprised how bad they sound at lows when you can really hear below 100 Hz.
 
PS. About Senn's. Some old school 4xx and 5xx open cans are much better than any of the 6xx series.

I don't think I have bad 650s because they sound just fine with E10K and with Magni 2.  Even with my iphone they don't sound too bright.  (No, I don't use 650 with iphone, just for testing.)  Only with the 08e amp do they sound too bright (lows are fine).  I don't think it's sibilance as "S" sounds normal, not sharp.  It's a broader frequency range in the highs.  Also it's not specific songs.  It's every song.  Too bright.  Only with 08e amp.
 
I have other cans I can try with the 08e to check the brightness.  Maybe I'll do that later, but I got this amp primarily for use with 650.

 

[sup27606]

I don't think I have bad 650s because they sound just fine with E10K and with Magni 2.  Even with my iphone they don't sound too bright.  (No, I don't use 650 with iphone, just for testing.)  Only with the 08e amp do they sound too bright (lows are fine).  I don't think it's sibilance as "S" sounds normal, not sharp.  It's a broader frequency range in the highs.  Also it's not specific songs.  It's every song.  Too bright.  Only with 08e amp.

I have other cans I can try with the 08e to check the brightness.  Maybe I'll do that later, but I got this amp primarily for use with 650.

The phones I use most with the 08e are the 650s (massdrop 6xx which are rebranded 650) and I didn't find any unusual brightness. 650s have more polite trebles than other phones, so if the 650s sound bright with your amp, I wonder how the brighter cans like AKGs and ATHs would behave. This leads me to speculate, if there is anything wrong with the amp. BTW, I tested another phone with this amp, the Audeze Sine which has more pronounced treble than the 650s and even that didn't sound bright at all.

BTW, I understand E10K has a built in DAC. Which DAC are you using with the 08e? Since the E10K did not sound bright to you, can you connect the pre-out of E10 to the 08e. That way, you know it's 08e that's causing the issue. Also make other people listen to the amp and get their verdict.