ThanatosVI
Headphoneus Supremus
All very good questions that I'd ask LTA support.
Have you heard the new Linear Tube Audio Z10e amplifier?
- Thread starter musicman59
- Start date
I have been using the Z10e exclusively with headphones but recently got a pair of Omega V8 HO monitors based on LTA and Omega recommendations for pairing with the Z10e. I have them set up close to the floor with wedges like a Klipsch Heresy or JBL L100 and boy what a great pairing and much better than the Kef R3. Both companies offer great customer support and have been a pleasure to deal with before and after the purchases. The Omega/Z10e cast a very wide and deep soundstage and is very holographic with a solid center image on vocals cast above the speakers which I find intoxicating. I also feel no need for a subwoofer and have actually plugged the ports since all of LTAs amps have a very powerful and well defined bass. I am somewhat of a audio collector and I have a couple of systems which feature different technologies and sound profiles and this one is definitely the chill system and the best eye candy. This is my favorite do-it-all system.
SolarCetacean
500+ Head-Fier
I had the chance to listen to the Z10e with some of my headphones at the Linear Tube Audio HQ this past afternoon. It was a lot of fun, and it's a very interesting product. I have both electrostatic and dynamic headphones and a do-it-all product that can also be expanded to either speakers or transformers for estats or ribbon headphones is a compelling concept.
I'll mostly report on its features, because unfortunately I didn't bring my current electrostatic amp (a CCS-modded SRM-006tS) along so I couldn't do a side-by-side comparison. On one hand, the Z10e did not transform any of my headphones into something radically different from what I'm used to on the Stax. On the other hand, it shouldn't have to; it should "get out of the way" and not limit the headphones in any way. When I listened to my 006t back at home, several hours after the demo, keeping in mind that auditory memory is what it is, I thought that bass sounded a bit thinner on the Stax amp vs what I heard on the Z10e. I brought my DAC to the demo, so it wouldn't be the DAC causing it. It matches with my impressions when I heard the Z10e at a meetup in February, but I'd love to have a future demo where I just brought one headphone and my amp along so that I could do a direct comparison.
* There was one audible quirk I heard in one track, "Rest of My Life (feat. Medyk)" by Culture Code. Towards the end of the track from 2:01 onwards, there's a hi-hat tapping in the background, and on the Z10e + X9000, there was this ringing sizzle during those hi-hats that I never recalled hearing on other amps. This ringing occurred on both DACs I used, so it wasn't associated with a particular DAC. I could not hear it at home on the Stax amp, and I don't recall hearing it on the BHSE when I demoed the X9000 on it. I don't know if it's just better treble extension or some sort of ringing that occurs at a particular frequency on the Z10e. I didn't notice other songs with substantial high-frequency content exhibiting that sort of ringing. Unfortunately, I didn't check if it also occurred on other headphones.
* The other quirk that affected sound was the "sweet spot" or "optimal range" of listening volumes. A few people have mentioned in this thread how the sound thins out below a certain volume level. I encountered that too, but it also extended to if I went above the sweet spot on the volume control. Below the sweet spot, the sound was thin, lacking in bass, shrill, and sharp. Then once I'm in the sweet spot, the shrillness and sharpness are gone, the bass fills in, and the sound transforms into being rich and weighty, without any shrillness or sharpness. Once I turn it up even more, then it starts to get a bit sharp in the treble again. And it's not like the sound level gets much louder when I turn it up to reach the sweet spot, it just becomes fuller. And below the sweet spot, while the sound is thin and shrill, it also produces this "ear pressure" similar to very strong active noise cancellation, like there's this invisible, uncomfortable pressure on my eardrums. It goes away when I reach the volume sweet spot.
I asked LTA's Nicholas about this and he advised that I enable Hi-Res volume control, which increases the number of volume steps to 199 from 100, with 0.5 dB increments. That made it much more useable for me. I'm a low-volume listener, and I was using the sensitive Sony MDR-Z1R on the Low Power output and I had almost no useable volume range at the default resolution with the balanced inputs. 8 was thin, 9 was better, and 10 was in the sweet spot but already louder than I normally listen. Hi-Res output allowed for a wider range of volume levels within the sweet spot. The sweet spot phenomenon was more noticeable on the regular headphone outputs than on the electrostatic output. Since I'd probably use the Z10e mostly as an estat amp, it's not the biggest deal, but it does slightly hurt the concept if the regular outputs are more limited. Nicholas mentioned that Hi-Res Volume and the Gain Level settings aren't meant to be used together. The hi-res volume is an improvement on the input gain setting, and I found that to be true. I could use the default 0dB gain setting and just use the hi-res volume control to find the right volume.
I'm not sure why this sweet spot exists. I thought it could be an internal gain-switching thing, but Nicholas told me that there's no gain switching going on inside the amp. I was told that there is some adjustment of the tube bias going on, but I don't know enough about how the amp operates to know if that could cause it. The sweet spot problem is the biggest issue that I observed with the Z10e. On every headphone I tried, I was able to find a useable volume within the sweet spot, but it may be an issue if I ever wanted to listen louder or quieter than usual. The only other functional issue I noted was a mild background hiss on the Z1R, which is a sensitive headphone. It was only noticeable when nothing was playing and it was very quiet, but still there. Sort of to be expected with tubes though.
So I am being rather critical here, nitpicky even, but that's because I'm also very interested in this amp. I'm trying to find the dealbreakers here, because if I buy this amp, I don't want to encounter any nasty surprises. I'll go into things that the amp does well.
* The control scheme is probably one of the best I've seen on an amp. There are 3 inputs, and the volume level is set and saved per input. This makes volume-matching very straightforward. I made good use of that feature in my demo to compare two DACs. The digital volume control makes it easy to know what volume you usually use rather than trying to eyeball the exact location of the knob. A nice feature is that whenever settings related to volume (gain level or hi-res control) are set, the volume level is reset to 0 so that you don't get surprised by volume jumps.
The menu system is neat too. While there are no physical buttons to enter the menu, it's accessed via the remote and the dot-matrix display for volume level and input is repurposed to display menu options in scrolling format. I thought that such a small screen wouldn't do well for displaying menu options, but it worked surprisingly well and I didn't feel like I was hindered by the small display with the text scrolling at a good speed - neither too slow nor too fast.
I didn't use the option, but the remote allows you to adjust the L/R balanced for the output. I wanted this feature for electrostatics which are more prone to imbalance, but I didn't need it for this demo and the amp seems to have better channel balance than my Stax amps at home. But it's nice to have the feature if needed. The remote also allows volume and input control as usual, which gives the amp flexibility for use in the living room or other places where I might not have the amp within arms' reach.
Finally, the physical design and operation of the amp are superb. It looks really nice, the volume knob is smooth to turn, and the control switches actuate cleanly and crisply. All of the tubes are enclosed for pet safety and it doesn't output all that much heat. My Stax amp seems to output as much heat from 2 tubes as the Z10e does with 10. I'm definitely very interested in hearing the Z10e again.
I'll mostly report on its features, because unfortunately I didn't bring my current electrostatic amp (a CCS-modded SRM-006tS) along so I couldn't do a side-by-side comparison. On one hand, the Z10e did not transform any of my headphones into something radically different from what I'm used to on the Stax. On the other hand, it shouldn't have to; it should "get out of the way" and not limit the headphones in any way. When I listened to my 006t back at home, several hours after the demo, keeping in mind that auditory memory is what it is, I thought that bass sounded a bit thinner on the Stax amp vs what I heard on the Z10e. I brought my DAC to the demo, so it wouldn't be the DAC causing it. It matches with my impressions when I heard the Z10e at a meetup in February, but I'd love to have a future demo where I just brought one headphone and my amp along so that I could do a direct comparison.
* There was one audible quirk I heard in one track, "Rest of My Life (feat. Medyk)" by Culture Code. Towards the end of the track from 2:01 onwards, there's a hi-hat tapping in the background, and on the Z10e + X9000, there was this ringing sizzle during those hi-hats that I never recalled hearing on other amps. This ringing occurred on both DACs I used, so it wasn't associated with a particular DAC. I could not hear it at home on the Stax amp, and I don't recall hearing it on the BHSE when I demoed the X9000 on it. I don't know if it's just better treble extension or some sort of ringing that occurs at a particular frequency on the Z10e. I didn't notice other songs with substantial high-frequency content exhibiting that sort of ringing. Unfortunately, I didn't check if it also occurred on other headphones.
* The other quirk that affected sound was the "sweet spot" or "optimal range" of listening volumes. A few people have mentioned in this thread how the sound thins out below a certain volume level. I encountered that too, but it also extended to if I went above the sweet spot on the volume control. Below the sweet spot, the sound was thin, lacking in bass, shrill, and sharp. Then once I'm in the sweet spot, the shrillness and sharpness are gone, the bass fills in, and the sound transforms into being rich and weighty, without any shrillness or sharpness. Once I turn it up even more, then it starts to get a bit sharp in the treble again. And it's not like the sound level gets much louder when I turn it up to reach the sweet spot, it just becomes fuller. And below the sweet spot, while the sound is thin and shrill, it also produces this "ear pressure" similar to very strong active noise cancellation, like there's this invisible, uncomfortable pressure on my eardrums. It goes away when I reach the volume sweet spot.
I asked LTA's Nicholas about this and he advised that I enable Hi-Res volume control, which increases the number of volume steps to 199 from 100, with 0.5 dB increments. That made it much more useable for me. I'm a low-volume listener, and I was using the sensitive Sony MDR-Z1R on the Low Power output and I had almost no useable volume range at the default resolution with the balanced inputs. 8 was thin, 9 was better, and 10 was in the sweet spot but already louder than I normally listen. Hi-Res output allowed for a wider range of volume levels within the sweet spot. The sweet spot phenomenon was more noticeable on the regular headphone outputs than on the electrostatic output. Since I'd probably use the Z10e mostly as an estat amp, it's not the biggest deal, but it does slightly hurt the concept if the regular outputs are more limited. Nicholas mentioned that Hi-Res Volume and the Gain Level settings aren't meant to be used together. The hi-res volume is an improvement on the input gain setting, and I found that to be true. I could use the default 0dB gain setting and just use the hi-res volume control to find the right volume.
I'm not sure why this sweet spot exists. I thought it could be an internal gain-switching thing, but Nicholas told me that there's no gain switching going on inside the amp. I was told that there is some adjustment of the tube bias going on, but I don't know enough about how the amp operates to know if that could cause it. The sweet spot problem is the biggest issue that I observed with the Z10e. On every headphone I tried, I was able to find a useable volume within the sweet spot, but it may be an issue if I ever wanted to listen louder or quieter than usual. The only other functional issue I noted was a mild background hiss on the Z1R, which is a sensitive headphone. It was only noticeable when nothing was playing and it was very quiet, but still there. Sort of to be expected with tubes though.
So I am being rather critical here, nitpicky even, but that's because I'm also very interested in this amp. I'm trying to find the dealbreakers here, because if I buy this amp, I don't want to encounter any nasty surprises. I'll go into things that the amp does well.
* The control scheme is probably one of the best I've seen on an amp. There are 3 inputs, and the volume level is set and saved per input. This makes volume-matching very straightforward. I made good use of that feature in my demo to compare two DACs. The digital volume control makes it easy to know what volume you usually use rather than trying to eyeball the exact location of the knob. A nice feature is that whenever settings related to volume (gain level or hi-res control) are set, the volume level is reset to 0 so that you don't get surprised by volume jumps.
The menu system is neat too. While there are no physical buttons to enter the menu, it's accessed via the remote and the dot-matrix display for volume level and input is repurposed to display menu options in scrolling format. I thought that such a small screen wouldn't do well for displaying menu options, but it worked surprisingly well and I didn't feel like I was hindered by the small display with the text scrolling at a good speed - neither too slow nor too fast.
I didn't use the option, but the remote allows you to adjust the L/R balanced for the output. I wanted this feature for electrostatics which are more prone to imbalance, but I didn't need it for this demo and the amp seems to have better channel balance than my Stax amps at home. But it's nice to have the feature if needed. The remote also allows volume and input control as usual, which gives the amp flexibility for use in the living room or other places where I might not have the amp within arms' reach.
Finally, the physical design and operation of the amp are superb. It looks really nice, the volume knob is smooth to turn, and the control switches actuate cleanly and crisply. All of the tubes are enclosed for pet safety and it doesn't output all that much heat. My Stax amp seems to output as much heat from 2 tubes as the Z10e does with 10. I'm definitely very interested in hearing the Z10e again.
laialbert
New Head-Fier
It is a bit silly that this is necessary, but I’ve had good luck with putting an iFi IEMatch+ in the path with the regular headphone output. I’m not sure if there is any downsides to doing that, but it sounds a lot better to me at lower volumes.
SolarCetacean
500+ Head-Fier
I have questions to clarify the phrase "straight off the tubes". I presume you mean the EL84s in this case? Does the electrostatic output of the Z10e go through the ZOTL impedance converters like the other outputs do? I was watching some of LTA's presentations/talks with David Berning about his ZOTL topology and it looks like the tube output is fed into the impedance converter which controls the output voltage to the speaker. To me, the phrase "straight off the tubes" implies that the estat output signal bypasses that impedance converter and is sampled directly from the tubes' anodes, but I might be misinterpreting that.
KDS315
100+ Head-Fier
From the net: "ZOTL technology involves a linear amplification process using a carrier frequency as well as not having a traditional audio output transformer, instead using air-core Impedance Converters. "
jtnt
Member of the Trade: Linear Tube Audio
The impedance converters generate the plate voltage for the tubes, but the audio signal does not go back through the impedance converters for the estat output, it comes directly from the tube to the estat output.
muhammedcakin
New Head-Fier
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Did you buy one? I’m thinking to forego the price point and purchase as well. It seems like an amp that should satisfy restlessness. If I buy one...I’ll pair it with the Stax SR-007 MK2.
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