The beauty of the TU-8900 is that it is a chameleon and can easily change its sonics if you want a more highly tone saturated enveloping sound just run it without negative feed back with Mullard input tubes and paper in oil output capacitors. Drawback is woolly bass and a rolled off frequency response top and bottom.
Want tighter bass and good frequency extension improved resolution use negative feedback modern caps having solid state rectification helps as does the Cossor WE300b the bass is one of its star qualities adding texture and gravitas to tone and timbre from top to bottom tying the sonic landscape together.
Having so much flexibility with running both 300b and 2A3 with or without NF combined with different input tube choices provides an abundance of opertunity to dial in the sonics to personal preference.
There is no right or wrong just great music.
Want tighter bass and good frequency extension improved resolution use negative feedback modern caps having solid state rectification helps as does the Cossor WE300b the bass is one of its star qualities adding texture and gravitas to tone and timbre from top to bottom tying the sonic landscape together.
Having so much flexibility with running both 300b and 2A3 with or without NF combined with different input tube choices provides an abundance of opertunity to dial in the sonics to personal preference.
There is no right or wrong just great music.
Going between NFB and non-NFB put me in an existential dilemma - how was the music intended to sound? Or is it completely subjective to my taste? Without the NFB 8900 sounds like a brawler, massively dense and rich and busy. With the NFB engaged it tidies up so much - very refined and elegant. Cleaner and better than how the music sounds in other amps. I suppose with the non-NFB it succumbs to classic tube trappings, and somehow the designer incorporated NFB to make it closer to solidstate while retaining the essence of the tube sound. I am still left wondering if I would get used to the sound without the NFB... It was... different.
Spot on!
One could make the case that the 8900 is 8 amps in 1 unit. The unique combinations of:
headphone amp/speaker amp
2A3/300B
NFB/Non-NFB
This is value on top of value IMO (it’s a kit which already is great value).
Very interesting. Perhaps I have been listening to Non NFB for a while and that is why I have been preferring the 300B to the 2A3. Under this mode, I found that the 2A3 really is too Mellow and warmth, losing bites and not lively enough Vs the 300B. I am trying the NFB right now, and you are correct that the amp sound faster, tighter, more controlled and even more extensions on both ends with 300B. Most obvious in the controls would be from the bass, it sounds more like a drum sets than a large bass, where as with NFB, it really started to show that it is Bass
Also worth noting is that the Non NFB started out harsh and sibilants and when warmed up, the mod is too sticky, also higher floor noises as well. The clarity seems to be somewhat veiled, and it gets much more softened and sweetened as it get warmer after a continuous operations of 4 hours or so. Thanks for bringing this to my attentions
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I mean, I see the appeal of the dual-purpose... but if I had a vote for a new Elekit product, it would be something dedicated for headphones. The way this amp puts resistors on the headphone output for attenuation just seems a little clunky.
Something designed for the lowest possible noise floor instead of power, and choosing a transformer that gives headphone-appropriate gain levels and a properly low output impedance? Man, I'd be all in. Think DNA Stratus or Stellaris as what you could do with a 2A3 tube and transformers specifically designed for headphone loads.
It might work fine for high impedance phones. But resistors on the output increase output impedance unnecessarily, and reduces damping factor needed for sensitive low impedance phones.
I'd much rather a headphone amp with an appropriate gain that doesn't need to be attenuated, and output transformers optimised for the load.
Idk, I have a full blessing with HD800S. Loving the amp by miles. After all , it is the ears that decides
Well yeah, high impedance phones, not that big a deal.
Although I'd still argue that for high impedance phones, OTL without series attenuation make more sense than a speaker transformer amp with series attenuation.
I'm not tring to poop on anything, just pointing out that a jack of all trades isn't always the best solution. I think a dedicated headphone design could be far better for headphones.
Personally I don't think the majority of regular headphone users will ever even hear of or be looking at the TU8600 after all its not really marketed as such only that it has some flexibility in impedance matching to make it more versatile for the end user with a wider range of headphones.
It's appeal is very squarely aimed at the speaker user who might on occasion use headphones.
I've run flee watt systems for the last 15years with both solid state and tube amps including a couple of Nelson Pass amps, Bottlehead, loads of integrated etc the TU8900 is definitely no slouch that's for certain.
Specifically with headphones do I prefer it over my Pass Whammy headphone amp or my Bottlehead Mainline I would say most definitely and they are both superb sounding highly regarded designed from conception to be *dedicated* headphone amps. Fyi I have a friend who owned both the DNA Stratus and Mainline at the same time he did a good comparison between them on headfi the DNA bettered the Mainline but not by much. Which it should do at three times the price and that didn't include the premium tubes in the Stratus that cost about the same as the Mainline on its own if I recall correctly.
One of the biggest concerns for me using a amp after the Dave is am I going to lose anything going through it compared to straight out of the headphone socket on my Chord Dave. The hd800 Dave combo sets a pretty high sonic bar easily besting my other headphone amps. With the TU8900 the answer is well not really subtle differences most notably a slight reduction in spaciality but nothing that's going to see me really favouring the Dave's headphone out over the TU800 from a preference view point.
The TU8900 I think is really only going to appeal to a very small fringe group of headphone users who have hard to drive headphones like Abyss AB1266, AKG 1000, Hifiman HE6 and running off the speaker taps.
I've been using my HIfiman HE6 off the speaker taps of the TU8900 fed by the Chord Dave and sonics wise it's hitting it right out of the park and into orbit.
As the saying goes the proof is in the pudding and that pudding is tasting mighty fine to me.
It's appeal is very squarely aimed at the speaker user who might on occasion use headphones.
I've run flee watt systems for the last 15years with both solid state and tube amps including a couple of Nelson Pass amps, Bottlehead, loads of integrated etc the TU8900 is definitely no slouch that's for certain.
Specifically with headphones do I prefer it over my Pass Whammy headphone amp or my Bottlehead Mainline I would say most definitely and they are both superb sounding highly regarded designed from conception to be *dedicated* headphone amps. Fyi I have a friend who owned both the DNA Stratus and Mainline at the same time he did a good comparison between them on headfi the DNA bettered the Mainline but not by much. Which it should do at three times the price and that didn't include the premium tubes in the Stratus that cost about the same as the Mainline on its own if I recall correctly.
One of the biggest concerns for me using a amp after the Dave is am I going to lose anything going through it compared to straight out of the headphone socket on my Chord Dave. The hd800 Dave combo sets a pretty high sonic bar easily besting my other headphone amps. With the TU8900 the answer is well not really subtle differences most notably a slight reduction in spaciality but nothing that's going to see me really favouring the Dave's headphone out over the TU800 from a preference view point.
The TU8900 I think is really only going to appeal to a very small fringe group of headphone users who have hard to drive headphones like Abyss AB1266, AKG 1000, Hifiman HE6 and running off the speaker taps.
I've been using my HIfiman HE6 off the speaker taps of the TU8900 fed by the Chord Dave and sonics wise it's hitting it right out of the park and into orbit.
As the saying goes the proof is in the pudding and that pudding is tasting mighty fine to me.
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