[newToAudio100]

Any more review on single vs dual mentor vs mj3?

 

[Erick Muller]

So I've been listening some more, and I broke out the Douk XLR switcher for some head to head comparisons of Mentor to Mjolnir 3. The chain is, Moode Raspberry Pi 4 USB to Bifrost 2/64 -XLR-> Lokius (in bypass) -XLR-> Douk Switcher -XLR-> MJ3/Mentor. MJ3 in high gain, Class A, Feedback off. Mentor in High gain. Both amps volume matched with a 440hz, 1k, and pink noise source file to the same tenth of a DB on Tungsten Single Sided. All interconnects are World's Best Mogami, and both output cables to the amps from the Douk are the same length.

Bass

No contest to me, MJ3 has more junk in the trunk here, for sure. Chokes for the win I guess. I tested on CZARFACE - All That For A Drop Of Blood, BigBoi - Kill Jill as well as a straight 20hz foobar generated wave file and the MJ3 has noticeably more sub-bass extension. The middle bass drop on Kill Jill (~35 seconds) is faintly present on MJ3 whereas on Mentor it's barely there. Mentor MAY have an edge in tightness, but I don't have a track that I know is good for testing that. Open to suggestions there.

Mids

Mids sounds about the same to me. Mostly listened on Billie Eilish's Your Power as some of her inflections can be too much on certain sets in the mids for me so it's one of my midrange goto's. Acoustic guitars sound similar to me on both amps, but I do need to spend more time here.

Treble

Mentor seems brighter here. Slightly. Whether that translates to more detail or just more treble I can't say for sure yet. I have not come across a detail in a track that doesn't also exist in MJ3, its just that Mentor sounds brigher. Some examples, Counting Crows - Anna Begins, around 1:38, Adam Duritz's esses are slightly more sibilant on Mentor, same track ~1:53 there's a tinkling sound top right of the stage that's a hair more pronounced on Mentor. On the right channel of Amber Rubarth's Tundra, someone needs to trim their nose hair. The whistling from it and some of the edges of percussion are more pronounced on Mentor. BT - The Antikythera Mechanism from 5-6 minutes there's a very high frequency ticking that extends up to 20khz in the background that sounds better defined/sharper on Mentor.

Stage

Mentor seems to have slightly more stage width than MJ3 and I mean slight.

Will update the thread as I listen more. I plan on trying the other gain modes on Mentor to see if that changes the bass situation. I still think it's a good amp, but I do wish it had the booty shaking bass extension of MJ3 to go along with its treble extension.

No problem running tungsten SS version then? at what volume and gain do you listen to them on both the MJ3 and Mentor?, I'm deeply interested in both these amps because I want to buy the SS version of Tungsten and my current amp(Aune S17) might be able to drive them well enough(Been running some numbers and my current amp might be able to drive Tungsten SS version at 109 dB, not planning to listening that high but I have some headroom) just wanted to get some impressions from people that own both amps and Tungsten to make an informed decision, it's not exactly peanuts we're talking about with both this amps at $1.2k usd both so I don't want any nasty surprises that I upgrade to one of this amps and find out that they're not much better at running tungsten than my current set up.

 

[Erick Muller]

Seems like Mentor got popular. I also don't know how affected their production is by the war, if they're still in Kharkiv they might be struggling.

Are they seriously still on Kharkiv? hell, even in Ukraine proper?, I assume that Flux Labs did the same as Rebel Amp, pack up their stuff and move to the states or somewhere else. Kudos to them for refusing to move and sticking to their guns.

Given that revelation, yeah it's a wonder they're still in full operation and shipping their stuff, so a few weeks of delay from an order should be expected given the very rough circumstance they're in.

 

[streaml1ne]

No problem running tungsten SS version then? at what volume and gain do you listen to them on both the MJ3 and Mentor?, I'm deeply interested in both these amps because I want to buy the SS version of Tungsten and my current amp(Aune S17) might be able to drive them well enough(Been running some numbers and my current amp might be able to drive Tungsten SS version at 109 dB, not planning to listening that high but I have some headroom) just wanted to get some impressions from people that own both amps and Tungsten to make an informed decision, it's not exactly peanuts we're talking about with both this amps at $1.2k usd both so I don't want any nasty surprises that I upgrade to one of this amps and find out that they're not much better at running tungsten than my current set up.

No problem driving SS Tungsten on either amp IMO. My volume matching setup is to play a 440hz non-replay-gained test track as well as a 1k track and a pink noise track and get the volumes matched to the same tenth of a db using a decibel meter. Both amps are in high gain and I think I was at about 91db on the meter with the 440hz track, but most of my tracks have a -5 to -10 db replay gain applied which is computed by foobar and moode uses. The end effect is my listening volume is around 80-85db. I'm planning on trying Mentor on medium and low gain to see if the bass comes up in those gain modes, but I need a couple days to do that testing. At the above volume matching settings I'm at about 2 o'clock on Mentor and 1-2 oclock on MJ3, however the relay ladder on Mentor does not appear to be linear and it gets loud real fast if I bump up the volume.

 

[Erick Muller]

No problem driving SS Tungsten on either amp IMO. My volume matching setup is to play a 440hz non-replay-gained test track as well as a 1k track and a pink noise track and get the volumes matched to the same tenth of a db using a decibel meter. Both amps are in high gain and I think I was at about 91db on the meter with the 440hz track, but most of my tracks have a -5 to -10 db replay gain applied which is computed by foobar and moode uses. The end effect is my listening volume is around 80-85db. I'm planning on trying Mentor on medium and low gain to see if the bass comes up in those gain modes, but I need a couple days to do that testing. At the above volume matching settings I'm at about 2 o'clock on Mentor and 1-2 oclock on MJ3, however the relay ladder on Mentor does not appear to be linear and it gets loud real fast if I bump up the volume.

Thx for your feedback, in your humble opinion, given that I enjoy really much the warm and lush sound that my S17 produces on 100ma mode, which amp do you think is a better fit for my taste? the MJ3 or the Mentor? now that you mention that both amps drive tungsten really well.

 

[streaml1ne]

Thx for your feedback, in your humble opinion, given that I enjoy really much the warm and lush sound that my S17 produces on 100ma mode, which amp do you think is a better fit for my taste? the MJ3 or the Mentor? now that you mention that both amps drive tungsten really well.

At the moment based on my listening that would be MJ3, but I do not have a lot of hours on the Mentor in total and I believe they recommend 100+ hours for burn in (if you're into that sort of thing), I also have not tried the other gain modes to see if the signature changes. That testing should be soonish.

 

[Erick Muller]

At the moment based on my listening that would be MJ3, but I do not have a lot of hours on the Mentor in total and I believe they recommend 100+ hours for burn in (if you're into that sort of thing), I also have not tried the other gain modes to see if the signature changes. That testing should be soonish.

Looking forward for your feedback on this regard, at this moment I feel the MJ3 is a better fit for my personal preferences, but I'm completely open to what Mentor offers sonically speaking.

 

[Majors]

I`m really not a fan of the FLA volume ramp up. Right at the start of listening levels you loose the fine adjustment needed and get large swings of volume. Not optimal in my situation.

 

[artist777]

I`m really not a fan of the FLA volume ramp up. Right at the start of listening levels you loose the fine adjustment needed and get large swings of volume. Not optimal in my situation.

Most likely the control algorithm is different. According to the website: "In this amplifier model, we have enhanced the volume control program for better system response and improved overall usability. This volume control eliminates the problem of volume imbalance between channels and enables you to finely tune the level even on high-sensitive headphones."

 

[DisalvoA992]

Does anyone have a setup that has a preamp before the Mentor stack? You can just nail both knobs on the master unit of the Mentor stack if they use the sync cable and control the output with the preamp.

 

[Majors]

Most likely the control algorithm is different. According to the website: "In this amplifier model, we have improved the volume control program for better system response and overall ease of use."

Yeah, I know it is touted as a feature but It`s more of a bug for me.

 

[artist777]

Yeah, I know it is touted as a feature but It`s more of a bug for me.

Perhaps I wasn't quite clear. This is indicated in the Mentor section and is about improving the operating algorithm of the relay controller relative to the previous FA-series.

 

[Ichos]

Volume adjustment is very smooth with fine steps that will not make sensitive headphones very loud with each click.

 

[Majors]

Volume adjustment is very smooth with fine steps that will not make sensitive headphones very loud with each click.

That is excellent news that they fixed what I feel is the only flaw with my FA-22. I was just responding to streaml1ne`s assesment
" however the relay ladder on Mentor does not appear to be linear and it gets loud real fast if I bump up the volume."

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[Ichos]

That is excellent news that they fixed what I feel is the only flaw with my FA-22. I was just responding to streaml1ne`s assesment
" however the relay ladder on Mentor does not appear to be linear and it gets loud real fast if I bump up the volume."

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I was listening yesterday with the Focal Clear Mg and I haven't experienced such issue. I am at work now but later today I will tell you how many clicks I need to get from silence to normal listening volume.