[bbball]

  I read that your amp has 3 selectable output impedances ranging from 0.1 to 120 Ohms. Even the maximum setting of 120 Ohms is not very significant compared to the T1's 600 Ohm impedance, so you may not perceive much difference. To a lower impedance headphone, the 120 Ohm output impedance is more significant so you can expect more difference in sound.

I see. One reason I am curious about this is I just not sure if the T1 can be fully driven by the Ember since the impedance is kind of high. 

 

[Tunkejazz]

   
...is the transparence help to enjoy your music?

Nah, it is a good slam in the bass

 

[Tunkejazz]

I have now been listening while in the office (total usage time of my Ember must be around 30h). I have experience quite a drift in the sound signature as it burns in, which I did not expect to be so dramatic. After 10 hours it literally became dull and flat. Now it is clean, weighty and crispy. Initially, I thought it was due to my Raytheon 6sn7gtb, but it actually sounds quite ok now, not too different from the Sylvania 6sn7gt that I could borrow from Johan.
 
I don't have problems with the hum, but I have noticed that many tubes pick interferences from all the wifi's and phones that are around in the office. Right on the corner of my table there is a sweet spot though
 
I will try to post my impressions with some of the tubes once I am sure it has settled, or whatever placebo effect that I may be experiencing is gone.

 

[rmouser]

  In my setup I was using a solid state amp as the preamp, and as far as I know, these don't add distortion. The changes I heard were mostly detail retrieval and speed related changes. Equalizers can boost/reduce certain frequencies, but don't generally actually add nuances in the recording that weren't audible before. Compressors on the other hand can change the speed (attack, decay, sustain, release) of sounds, so comparing the way daisy-chained amps to the way compressors effect the speed would be more of a valid argument.
 
Double-amping is dependent the output amount and gain settings of the two amps, especially the first amp, so not all double amp setups have good synergy together. It's generally more efficient to use the lower spec amp first, otherwise the more powerful amp's output would be cancelled out. You can also read from some others who have gotten a marvelous result from double amping here and here.
 
"For what it's worth, the 1/4 to RCA between my Capella and both my Garage 1217 tube amps works extremely well. More power, headroom, sound-stage, no distortions-but I limit the vol on the Capella to around 10 and the Garage amps settle at around 10-11 for loud realistic listening. Actually this set up sounds better than connecting RCA to RCA, and you can, of course, use all the tweaks."
 
"Alright, I made it work and it does sound better. Connection is Capella 1/4 jack to H10 RCA. 
All relative but: bass is tighter and sub-bass is much stronger. Much more detail extraction, more organic sounding (especially vocals!), more dynamic, soundstage is holographic, much more expansive..."

You use a lot of descriptive words here: attack, decay, sustain, release, synergy, extraction, organic, etc. I doubt that you are that well trained and know what the words actually mean. Are you just repeating words you read?
 
In agreement with those that state adding more circuitry to the signal is going to add more of your words to the sound.

 

[DecentLevi]

I realise it's sometimes difficult to tell how experienced other users are on these forums. But checking their profile first, asking them privately, or even trying the said concepts first-hand can allow you to draw a practical conclusion first. (gathering evidence and testing things is the only valid way of finding the truth).
 
I in fact do have quite a lot of background with the topics I was mentioning about. I have been dabbling with recording / manipulating sound effects since the mid 1980's, and finally in recent years I started taking it more seriously, on the audio production side. I have also been into the audiophile hobby for about 7 years. Funny thing is I just realised I'm more experienced with sound design / mastering than the audiophile hobby, so feel free to let me know if I'm using too much mastering-related jargon, or just ask me and I will do my best to explain these concepts when I can. I don't claim to be an expert on either topic, and just like all of us, I'm still learning. But I can assure you that I am exclusively familiar with the points that I mention.
 
Starting with the terms "attack, decay, sustain, release" (ADSR): this is an 'envelope' which is essentially a visual representation of the volume of a sound over time in relation to: the length until the start of the initial point of the sound, the length of this initial point, length of the main section of the sound, and the length until the sound completely fades out. While this may sound like a lot, many sounds are actually quite fast and the most audible parts are the attack and release. While this term usually relates to synthesizers and compressors, it also relates to amplifiers and headphones/speakers in that one of their main functions is to reproduce the PRaT (pace, rhythm & timing) in a realistic way.

 ​

Both of the above functions are related to dynamics / speed of sounds, and quite clearly, a main difference an amp makes is refining the original source so that you can hear an improvement with things like punchyness / impact, detail / clarity, etc. Therefore it stands to reason that two amps connected in series should be able to provide a more detailed sound.
 
In regards to the idea that a longer signal path only adds distortion / subtracts from the original source: On one side of the coin this could be true. From an electrical standpoint, a longer cable and more components should reduce the detail of the original signal. But from a 'listeners' perspective, Consider what role do these play: a transformer boosting current an a power grid, a USB signal cleaner such as the Wyrd, or a huge amp with dozens of circuits vs. a small amp? As you can gather, a longer signal path does not always amount to a reduction in perceived fidelity. Rather it can enhance certain elements.
 
I have tried multiple combinations of double-amping: multiple critical-listening sessions with a high end source chain and headphone, A/B'ing dozens of times with the same portion of the same song being played on a loop, and I have realised that there is an absolute undeniable increase in the amount of detail and dynamics / speed. Several others have recognized this as a valid configuration as well, such as the ones mentioned above from the Beresford Capella thread, and also when several highly reputable Head-Fi'ers had tested the Geek Out v2 at a recent meet - it was double amped and they were all in unanamous agreement of how good it sounded.
 
I would however like to revise my initial review of double-amping with the Ember amp. During critical listening I chose the double-amped setup as the best (with Capella amp to Ember via headphone to RCA cable). But later I realised that while this sounds more detailed and 'fast', the highs actually sounded too analytical for average listening sessions and caused a strange effect on the lower frequencies, almost as if the bass was more distant sounding and had a stereo phasing issue. So with double-amping (daisy chaining), synergy plays a major role, possibly even moreso than with normal audio rigs. In order to utilize the most efficient gain stage, it's important to place the most powerful amp at the end, with the lower power amp first, also to reduce the chance of overloading the input stage of the 2nd amp. So basically I was just trying to encourage anybody who has a medium spec amp such as the Magni, O2 or Capella to go ahead and give it a try as a 'preamp' into the Ember to see if it just might make things sound even better for you. And of course, not all setups yield good results together.
 
PS - The words from my previous posts in italics were a quote from another user who had heard an audible improvement from double amping. And yes I understand all of the words I use. FYI here is the Head-Fi glossary of describing sounds.
http://www.head-fi.org/a/describing-sound-a-glossary
 
 

A few other quotes in support of this theory:​

Quote:

  +1 DecentLevi
 
Yep... I think this discussion is for what someones ear hears.

 
Quote:

  Agree.
The difference is between electronic detail enhancement and aural detail perception. Adding such components can't increase electronic detail. However, if the added audio components relatively enhance certain audible frequencies the ear may perceive this as added detail. For instance, if I am listening to a flute concerto I will hear the flute's higher frequencies more clearly with a K701 than an X1, even though the source and amp are identical for both cans. Presumably the Capella, working as a pre-amp in the situations sited, is just altering certain audible frequencies in a way which enhances the sound of certain key instruments making them sound clearer and more detailed.
Distortion is more difficult for me because some sounds awful, some sounds euphonic and some is inaudible. The Capella as a preamp appears to produce only the last two of these in the set ups mentioned, which is fortunate.

 

[connieflyer]

According to this, you are listening to an altered signal, you can achieve the same results by combining the signal through processors and graphic equalizers, dacs and through other software programs like Suzie Q and alter the level and attack of the signal at any point you wish to attain a (better, louder more clearly deliniated) sound at the frequency that does not exist on the original recording.  Why not ask the artist what he meant or the recording engineer why he chose the mix he did.  The mere fact that I can alter a song to match my tastes does not make it better, just different from someone else preception of what was meant to be heard.  You like it like that go for it, but don't make claims that it is superior in some way just because you played around with multiple amping.

 

[rmouser]

And you can actually hear all of those factors with multiple instruments playing and differentiate between them?

 

[Solrighal]

I'm of the opinion that as soon as you introduce a valve into the chain you fundamentally believe in EQ. If you don't then buy an O2 and be done with hi-fi forever. It's total nonsense to suggest that just by lengthening the signal path you are improving the end result. You may well find the end result more preferable but it is not better.

 

[Amish]

 
 
Damn I love this tube. Oh and of course the Ember!

 

[Tunkejazz]

@HOWIE13
where did you get your volume knob? ...it looks terrific in full metal!

 

[HOWIE13]

  @HOWIE13
where did you get your volume knob? ...it looks terrific in full metal!

 
 
Hi - I presume you mean the one on the Horizon on my profile picture.
I got it from a seller in China-here's the link:
 
http://www.ebay.co.uk/itm/321272824594?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
 
The picture on his webpage shows it as having a black rim but it came as completely silver. It might be worth checking with the seller that he will be sending you a completely silver one, if that's what you like.
It fitted fine on the Horizon and really helps fine tune the vol.
Good luck!

 

[vaibhavp]

does anyone know how attenuation module work??
 
its like an op amp with resistors on top. if I remove it, it does not work. do I have to buy separate module to attenuate?

 

[iancraig10]

We were discussing this on DIYAH. I don't think they're available yet. I suggested a cheap adjustable patch wire made by Shure, but Solderdude was saying that this was the equivalent of raising the output impedance. He then suggested making a patch lead until modules became available.

There's also the EQ unit on simmer!!

 

[btrancho]

does anyone know how attenuation module work??

its like an op amp with resistors on top. if I remove it, it does not work. do I have to buy separate module to attenuate?

The attenuation module is simply a pair of resistors mounted in a DIP socket. There is no op amp. They attenuate the input by adding resistance when you choose the low attenuation setting. They are bypassed when you choose the high setting. I would assume that if you set the Ember to the low setting but remove the attenuation module you are breaking the circuit.

You attenuate by leaving it in place and choosing the low setting. You can change the resistors to change the attenuation. The higher the resistor value the more attenuation.

 

[richard51]

I will like to give some revised experience of mine with receiver driving planars  directly from the speakers out (mine was Hitachi sr 904 a good one).. First i made this attempt with  a powerful receiver before i had added the sorbothane mod adequately to my HE 400, and the result of this experience was at first better for some reasons (power add presence) with the receiver than with the Ember amp that i had put after that on preamp function for my speakers at this time... Second i go on with the receiver when i discovered the right manner to put the sorb, because  the result was way more  better also  with the receiver ( i had not connect the Ember at this time with the new sorb mod of mine) ...BUT yesterday i changed my cabling and decide to try anew the Ember with the sorbothane modification i had rightly implemented... WOW ! the detailed soundstage and subtle presence of the sound was more preferable for me that the brute force of the receiver now ...The effect of the sorb mod  version 2 was more pleasurable, more sensitive, and more effective with the Ember...Hence the Ember is there to live with me... 

 
best regards to you all...
 
 
p.s. Sorbothane mod is more important than a change of amplifier for the HE 400 like Estrelow said about the Stax  headphones, i confirm his opinion... The Ember is a very, very good amplifier for his price probably without competition..