[Beefy]

Have you listened to Grado 3000x or RS1X via a Feliks Audio OTL AMP? Or any OTL for that matter. I've been listening to Grado for decades. I know how they are supposed to sound. The fact that they sound as good or better on this particular OTL amp than the best SS amp I've had is a fact for me. I don't notice bloated bass, the Grado sparkle is intact and wonderful. They are wonderful headphones on the Feliks, and garbage on the Valhalla 2.

Better check your measurements!

Not the Feliks specifically, and not the RS1X specifically, but every Grado and other low impedance phone out of every OTL I've heard follow exactly the same pattern. Elevated but less-impactful bass, less sparkle in the treble, mids a mixed bag. It all makes perfect sense from the high impedance and lower damping.

As to Feliks vs Valhalla? Maybe you've hit a magic synergy. Great. Still seems like a weird unicorn for anybody to chase.

 

[Hyde00]

Not to knock headphone science, I mean if it weren't for science and measurement then we wouldn't have nice dac and nice amp like we have today.

I guess it only bugs me when the measurement crowd stops at "it measures bad so I don't even need to listen".

As with everything in life we need to do things moderation. For example I like my coffee and tea with sugar and cream. But the purists might argue "you should drink your coffee black as how the barista intended". But I like how my coffee taste with sugar and cream. And I guess it's impossible to tell scientifically if that I will like my coffee/tea better with 2 sugar 2 cream, or 3 sugar 3 cream? Or 100 sugar 100 cream? Again...... moderation and to taste.......

Anyway...... I sidetracked a bit. Now back to point, I have Project Solstice hybrid tube amp. It has 3 output impedance setting that you can switch on the fly.

Project Solstice
Low = 0.1 ohm
Mid = 31 ohm
High = 68 ohm

If you just look at numbers then logically speaking you'd think for Lawton TH900 (25 ohm) it would sound best with the low (0.1 ohm) setting. But to me the mid setting (31 ohm) actually sound the best despite being "wrong". Low (0.1 ohm) just sound too cold/sterile like most solid state amps. High setting (68 ohm) has the best vocal but it start to skew the frequency too much and the rest of the spectrum is unbalanced. So I ended up just leaving it at mid (31 ohm) setting all the time.

I'm pretty sure there is a "sweet spot" somewhere between 20 to 40 ohm output impedance that still work well with 25 ohm headphone.

I couldn't find the measurement number for Feliks Echo MK2, but I wouldn't be surprised if the output impedance falls somewhere between 20 to 40 ohm.

Another 2 tube amp my friend recommend for Lawton TH900 are:

Shortest Way SW51+
Low = 27 ohm
High = 54 ohm

Hagerman Tuba
Low = 5 ohm
High = 35 ohm

He didn't specifically tell me the setting he used but I'm going to take an educated guess and say for Shortest Way SW51+ it would probably sound good with low setting (27 ohm) and Hagerman Tuba probably at high setting (35 ohm).

If we go by the 1/8 rule, then 25 ohm / 8 = 3.125 ohm. Meaning anything higher than 3.125 ohm output impedance will impart coloration to my Lawton TH900.

Though not saying 0.1 ohm is always bad, my Lyr 3 is 0.1 ohm and it sounds great. Just..... I guess you never know until you physically try it.

Anyway I've rambling on for too long LOL. Also maybe not apples to apples because my amps are hybrid amps. What I'm trying to say is, I only found out I like this because I tried. If I just follow numbers I'd never discover this.

Cheers!

 

[Luckyleo]

Not the Feliks specifically, and not the RS1X specifically, but every Grado and other low impedance phone out of every OTL I've heard follow exactly the same pattern. Elevated but less-impactful bass, less sparkle in the treble, mids a mixed bag. It all makes perfect sense from the high impedance and lower damping.

As to Feliks vs Valhalla? Maybe you've hit a magic synergy. Great. Still seems like a weird unicorn for anybody to chase.

Okay, as a less articulate way to same something, which may or may not be rude (probably is) you don't know what your talking about as it relates to my experience! Simple as that. Stop telling me what I am hearing is garbage and wish me well for enjoying my music.

Just saying.

Hope you enjoy your music as much as I enjoy mine! LOL

Leo

 

[Beefy]

Okay, as a less articulate way to same something, which may or may not be rude (probably is) you don't know what your talking about as it relates to my experience! Simple as that. Stop telling me what I am hearing is garbage and wish me well for enjoying my music.

Just saying.

Hope you enjoy your music as much as I enjoy mine! LOL

Leo

I'm not quite sure why you feel so attacked, because that wasn't the intention. I specifically said why I thought someone might prefer the well-known effects of high Z out, 'wrong' was specifically in air quotes, and I certainly didn't use the word garbage.

 

[J Ottawa]

Not to knock headphone science, I mean if it weren't for science and measurement then we wouldn't have nice dac and nice amp like we have today.

I guess it only bugs me when the measurement crowd stops at "it measures bad so I don't even need to listen".

As with everything in life we need to do things moderation. For example I like my coffee and tea with sugar and cream. But the purists might argue "you should drink your coffee black as how the barista intended". But I like how my coffee taste with sugar and cream. And I guess it's impossible to tell scientifically if that I will like my coffee/tea better with 2 sugar 2 cream, or 3 sugar 3 cream? Or 100 sugar 100 cream? Again...... moderation and to taste.......

Anyway...... I sidetracked a bit. Now back to point, I have Project Solstice hybrid tube amp. It has 3 output impedance setting that you can switch on the fly.

Project Solstice
Low = 0.1 ohm
Mid = 31 ohm
High = 68 ohm

If you just look at numbers then logically speaking you'd think for Lawton TH900 (25 ohm) it would sound best with the low (0.1 ohm) setting. But to me the mid setting (31 ohm) actually sound the best despite being "wrong". Low (0.1 ohm) just sound too cold/sterile like most solid state amps. High setting (68 ohm) has the best vocal but it start to skew the frequency too much and the rest of the spectrum is unbalanced. So I ended up just leaving it at mid (31 ohm) setting all the time.

I'm pretty sure there is a "sweet spot" somewhere between 20 to 40 ohm output impedance that still work well with 25 ohm headphone.

I couldn't find the measurement number for Feliks Echo MK2, but I wouldn't be surprised if the output impedance falls somewhere between 20 to 40 ohm.

Another 2 tube amp my friend recommend for Lawton TH900 are:

Shortest Way SW51+
Low = 27 ohm
High = 54 ohm

Hagerman Tuba
Low = 5 ohm
High = 35 ohm

He didn't specifically tell me the setting he used but I'm going to take an educated guess and say for Shortest Way SW51+ it would probably sound good with low setting (27 ohm) and Hagerman Tuba probably at high setting (35 ohm).

If we go by the 1/8 rule, then 25 ohm / 8 = 3.125 ohm. Meaning anything higher than 3.125 ohm output impedance will impart coloration to my Lawton TH900.

Though not saying 0.1 ohm is always bad, my Lyr 3 is 0.1 ohm and it sounds great. Just..... I guess you never know until you physically try it.

Anyway I've rambling on for too long LOL. Also maybe not apples to apples because my amps are hybrid amps. What I'm trying to say is, I only found out I like this because I tried. If I just follow numbers I'd never discover this.

Cheers!

There was a time when maximum power transfer occurs when source impedance = load impedance = ohm's law calculations in a series circuit. I know we all want low source impedance in order to have the higher damping factor possible, with all it's benefits, but what you say seems to impart an efficient transfer of Power (and it's spectrum derivative).

 

[jonathan c]

To my ears yes, but I'm no SBAF

... don't discount yourself ...

 

[Hyde00]

There was a time when maximum power transfer occurs when source impedance = load impedance = ohm's law calculations in a series circuit. I know we all want low source impedance in order to have the higher damping factor possible, with all it's benefits, but what you say seems to impart an efficient transfer of Power (and it's spectrum derivative).

I don't fully understand the technicalities but I'll agree with you.

 

[Xerosnake90]

Hey everyone,

I'll be snatching up a Bifrost 2/64 as soon as someone decides to get rid of theirs. I'm thinking of upgrading my Midgard to either the Lyr+ or the Maximus. Can anyone offer impressions on both with the 2/64? I like that the Lyr can use a tube or go Solid state, and I'm hearing the Pietus is nice and warm as well. I prioritize detail and a holographic soundstage

 

[AcousticMatt]

I'm also really interested in getting one of these amps myself.

Curious how it sounds with my headphones in my signature (everything but Susvara really) if anyone's using it with the same headphones. I do mainly use Caldera and Atrium Closed though, so those would the prime ones I'd be listening on.

I did read the FAQ part about the differences between the DAC card options, but I'm curious if anyone has compared both or just have any thoughts on their experience liking either.

 

[rjones36]

Just wanted to chime in here and report something that just now happen to me. I have seen a few folks report an issue with a "scratchy pot". I was not experiencing this.. until I had the Pietus Maximus sitting on top of my Gustard U18 DDC. It was happening at about the half way point on the knob. It really wasn't a scratchy pot as it really was static noise I was hearing. If I put my hand on the DDC while turning up the volume, then it went away. I then move it away from other equipment and off to the side by itself as I had it once before. Now no longer an issue. So... if anyone is having this issue, try not stacking the unit with other equipment and see if it helps.

 

[Aerocraft67]

Tried out the PM preamp function on my studio monitors. Plenty of flexibility to tweak the monitor volume with the PM gain & volume. No stereo channel imbalance at low volume.

Plenty of volume dial range with the middle gain setting around 9:00, with the monitor volumes set at 11:00 or so. High gain renders listenable range around 7:30—too narrow to adjust effectively. Low gain allows a wide swing of the dial, but ramps up sharply at 3:00. Satisfying precision, but too fiddly to dial in.

I use high gain for HD 8XX. So I'll need to be mindful of pulling the jack and blasting the monitors.

HD 8XX listenable volume is pretty tight around 8:45 or so in high gain. A bit tighter than the monitors in medium gain. The 8XX listenable range is 11:00–1:00 or so in medium gain. That's a more logical range and more precise than high gain. But I actually prefer the tighter tolerance in high gain. I can dial in the right volume quicker and fiddle with the volume less.

I figure I bought the amp to deliver high power for high impedance headphones, so let it rip.

 

[Tbone289]

@michael2v LOL I mean........ the SchiitTalker is not wrong, it's just things are very confusingly named. So it might seem like it's talking about the wrong thing, let me clarify:

Modi Multibit 1 = There are 2 versions with different chips to my understanding for Modi Multibit 1, hence V1 or V2. Both are actually referring to Modi Multibit 1.
Modi Multibit 2 = The current gen Modi Multibit, not to be confused with V2.

There were (at least) three versions of Modi Multibit (1).

• V1
• V2
• V2 w/OPA2156

"V2" refers to a revision in the firmware chip in 2018 to improve measurements, and late in production the Op-amps were changed from AD8512 to OPA2156, which is also stated to be an upgrade by those few who have compared them. The V2 firmware chip has a sticker applied with code "MD218".

 

[RayMets1]

Has anyone here compared side by side the Pietus Maximus to the Lake People G111 Mk2?

 

[NewEve]

Any one here has had the chance to compare the Jotunheim 2 with MultiBit card to the Pietus Maximus with MultiBit card — or perhaps someone more experienced might be able to guide me in terms of what I might expect? Thanks

 

[audiowhatfi]

Tried out the PM preamp function on my studio monitors. Plenty of flexibility to tweak the monitor volume with the PM gain & volume. No stereo channel imbalance at low volume.

Plenty of volume dial range with the middle gain setting around 9:00, with the monitor volumes set at 11:00 or so. High gain renders listenable range around 7:30—too narrow to adjust effectively. Low gain allows a wide swing of the dial, but ramps up sharply at 3:00. Satisfying precision, but too fiddly to dial in.

I use high gain for HD 8XX. So I'll need to be mindful of pulling the jack and blasting the monitors.

HD 8XX listenable volume is pretty tight around 8:45 or so in high gain. A bit tighter than the monitors in medium gain. The 8XX listenable range is 11:00–1:00 or so in medium gain. That's a more logical range and more precise than high gain. But I actually prefer the tighter tolerance in high gain. I can dial in the right volume quicker and fiddle with the volume less.

I figure I bought the amp to deliver high power for high impedance headphones, so let it rip.

lol I think in a perfect world I'd say get external dac is better.

I just cheaped out to save some cost. But otherwise yeah that would be my recommendation.

lol to be honest I'm not sure, but from educated guess and from what I read......... maybe between THX AAA and Magni Unity?

One review I read is that Magni Unity is more colored sounding.

Something to keep in mind is that from what Jason's explanation is that Magni+ volume pot has slower taper. While the Piety volume pot has faster taper (their old style).

What this means is that Magni+ has more usable volume range for easy to drive headphones, while Piety volume pot works better for hard to drive to headphone.

This translates to LOUD when using TH900 LOL, probably the same on Grado. Otherwise sounds good just LOUD.

So I don't recommend Piety for Grado. PMax they addressed the issue with volume so in terms of volume it's great. But PMax in general sounds smooth and smooth treble.

I've only had it for 2 days so I can't put my handle on it yet, but it feels a bit like listening to something very edgy and exciting like TH900 or Grado but then tame it down smoothly. It's like buy the beefiest angriest muscle car but drive very slow and quietly. I'm still not too sure how I feel about this yet....... very confused........

As it stands I'm still not too sure if I would recommend PMax for TH900 or Grado, my suspicion is that it pair better with 300 ohm headphones such as HD800S or ZMF headphones... though I don't have those headphones so I can't tell you if this is correct or not.

th900 on low gain at 1-3 is where I was listening and it was very pleasant………..low gain is really LOW gain lol!