Technically SUPERIOR - Zahl HM-1 headphone amp review

[@PassionforSound]

Mark, the owner of this amp, reached out to me after the review to let me know that the power cable from the transformer to the amp can actually be ordered to length. The short length on his unit is what suited his rack so please disregard my comments about the short "umbilical cord" length. And thank you to Mark for the clarification/correction!

[@TheVeganVicar]

Thanks for the engaging review, Lachlan! I'd love to see a comparison of the new DCA electostatics and the HiFi Man Susvara. P.S. Nice hoodie, but I am glad that I escaped the bitter Melbourne winters in 1975. ;)

[@PassionforSound]

I'm not currently setup for electrostatics, but hope to get something worked out in the future. 🙂 My wife and I fantasise regularly about moving north again. Strangely enough, it normally happens around this time of year 😁

[@PassionforSound]

@pt265 I'm still working my way into speaker reviews so I'm probably not the best source of information right now. I can say that the Harbeth P3ESR XD sound absolutely wonderful, but I don't have a wide range of direct comparisons yet.

[@nimzerz2422]

One of your best reviews so far IMO. Your descriptions really helped me picture exactly what to expect from each of these amplifiers in both sound and user experience.

[@PassionforSound]

Thank you. Glad to hear it's so helpful 🙂

[@johs12345]

This makes me all the more excited for your upcoming Phonitor XE review 🙌🏼With your in-depth reviewing style, I'll imagine that I will learn a bunch. Thanks for doing these comparisons in reviews too. Really helps!

[@PassionforSound]

My pleasure! I hope the Phonitor XE review lives up to the expectations. Glad the comparisons are helpful. When I'm looking for reviews, I always prefer reviews with comparisons too.

[@MikePio]

One of the best reviewers on KZbin and one that I always trust. Keep up the great work.

[@PassionforSound]

Thanks Mike - I appreciate it! 🙂🙂

[@peytonsnead3114]

Lachlan, doing what he does best. Evaluating audio equipment based on different listener use cases and preferences.

[@PassionforSound]

Thanks Peyton. Hope it was helpful 🙂

[@peytonsnead3114]

@@PassionforSound lets just say i won't be chasing the diminishing returns of which you speak, but i am fascinated by your ability to bring so much insight even when evaluating a near perfect amp. Drive on!

[@peytonsnead3114]

@@PassionforSound these comments on your reviews speak volumes 😊

[@thelastrhino2581]

Amazing review. Your thoughts on crossfeed were exactly what I was looking for. The fact that you covered it so thoroughly shows your high level of professionalism. Well done!

[@PassionforSound]

Thanks Rhino. I'm glad you found it helpful!

[@shawnpwatsons1]

I imagine you learned a lot from this review in terms of where the limits of technology can go, how feedback changes the sound, enjoyability vs. technicality, and value--all in one fell swoop. This is why these reviews of TOTL equipment are still fascinating even though I know I'll never be able to go there financially. That said, I need a pair of these for my downstairs half-bath and my garage man-cave.

[@PassionforSound]

Yes, it's fascinating to hear what absolute no compromise engineering can produce compared to "lower" level gear. It's clearly a better amp than anything else I've tried from a technical standpoint, but I also don't miss it since it went back to its owner.

[@rodm1949]

Your catalog of options are overwhelming, I have always kept in mind that you can not unhear something. Can't imagine your delema when you decide to listen to music. The Aiyima Smsl 12at7 AMP with 3 tubes is looking very intriguing. Your insight is much appreciated as always and your neutrality is impressive. Knowing a point of contention where options are better than being in one purchase.

[@PassionforSound]

Yes, too many choices can be a bad thing for sure! That's where tube amps can be extra dangerous with all the tube options they present! 😁

[@aceofspades6667]

There are a few more expensive hp amps out there. Viva egoista, Trafomatic primavera, riviera aic-10, Aries cerat genus, woo wa33 elite and there are a few from Japanese manufacturers (mass Kobo and Oji). I think you would really enjoy both the Trafomatic and Riviera if you ever get the opportunity to review. Well done review this was a fun one. Looking forward to your soloist GT2 review with the upgraded PS. Sounds like a solid value for the price to performance. A bit of op amp rolling might smooth out the mids and treble sparkle.

[@Michael_mki233]

You beat me to it, ace. I got less than 20 seconds into the video before I was on my way down to comment this, lol.

[@PassionforSound]

Thanks for raising my awareness! I did actually know of some of those now that you've jogged my memory, but there's still so much I haven't tried!

[@OzSteve]

Another great review. Love your take on reviews. Keep up the superb work mate

[@PassionforSound]

Thanks Steve!

[@RoastyGav]

The umbilical cord from the power supply box can be specced up to a max length of 1.5 m. This can be requested upon ordering. Should make for easier positioning.

[@PassionforSound]

Yes, Mark (the owner of this amp) reached out to me to explain his choice of length after the video was produced. There's a pinned comment to address the error, but I couldn't change the video content by that time.

[@rodm1949]

Just put a 1952 RCA 6AS7G in my WA3 and feeling guilty -- love it that much. At every step I didn't think sound can get any better, so glad I didn't stop.

[@PassionforSound]

Glad you're enjoying it!

[@tommymai3062]

How does the sound compared to the Phonitor 2 in the back there ? I’m sure it’s better but can you please be honest, is it a dramatic difference ?

[@PassionforSound]

I actually discuss this exact comparison in the video. In short, the HM1 is on a different technical level, but both are equally excellent sounding amps from an enjoyment perspective. The Phonitor is smoother sounding with less separation.

[@equilibrium2147]

This is the best, highly informative, precise review video about headphone amp… 👏👏👏👍🏼🇺🇸

[@PassionforSound]

So glad you liked it! Thanks for letting me know 🙂

[@Nephilim-81]

Holy moly! What a great review! Can’t believe you got this. I imagine it wasn’t easy. 😮

[@PassionforSound]

It was actually very easy thanks to a generous channel patron/viewer. 🙂 Couldn't have done it without him.

[@reptidan]

I love the different price catagories you review in! I’ll never buy an unit kike this. But its very cool to get the know the product nontheless.

[@BillyKueekSG]

Woahhhhh way out of my league and I’ll never know about this amp without your reviews, so thank you! I WS typing this and wanted to ask about the 23R when you brought it up. I am happy with my current equipments and small collection of headphones. I am looking into a pair of speakers but don’t have the right room for it so still undecided. The price of this amp, I can get a pair of KEF LS60 speakers.

[@PassionforSound]

I've got some other gear coming up that might be a better choice for speaker AND headphone listening without breaking the bank. 🙂

[@BillyKueekSG]

@@PassionforSound looking forward

[@MisterChibs]

Great review Lachlan! Where does the Chord TT2 fit in as far as it's amplification?

[@MistaLova-Lova]

I was going to ask the same question since you used to use the TT2 as your reference point of clean amplification. What happens when you hook this beast up to the TT2 as opposed to plugging your headphones directly into the TT2? 😀

[@PassionforSound]

Great question! It's rare to find an amp stage that's as transparent or more transparent than the TT2 onboard amp, but the HM-1 is next level. I've found lately that a few amps (HM-1, new Soloist 3X GT, AMP-23R and maybe Phonitor XE) are able to either extract even more detail from the music (HM-1) or bring character such as soundstage size or pleasing colouration while not damaging the overall sense of resolution (AMP-23R). I'll have to test vs the TT2 specifically for the upcoming Soloist 3X GT update and the Phonitor XE reviews

[@MisterChibs]

@@PassionforSound looking forward to that! The TT2 is up there in price too but you get what I would guess is a world class DAC in the package. One day I’ve gotta demo it. 🍻

[@joseluishernandezseptien]

Hi Lachlan! Thank you for this great review! Do you think the HPA4 gets close enough in performance to the HM1?

[@PassionforSound]

It all depends on what you mean by "close enough". The HPA4 (like most headamps) is still a fair way from the HM-1 in performance, but most amps are.

[@joseluishernandezseptien]

@@PassionforSound I see. I was wondering if it has similar tonality, speed and clarity. I wish I could listen to the HM1 one day. Thank you for the reply! You are the best :)

[@PassionforSound]

No. Unfortunately, nothing really does. I think that the HPA4 is actually probably a bit over priced these days since the price rise and other options like the Burson Soloist GT, Ferrum Hypsos & Oor, etc. likely make more sense.

[@joseluishernandezseptien]

@@PassionforSound I agree with you, the HPA4 at the current price increased is asking too much. I do have it and value its pre-amp functionalities as well, but $3600 with the remote is too much. I bought it used at a good price but was looking for something that could have better synergy with Susvara and HD800S. Thank you again, Lachlan!

[@User_not_found_403]

I'm trying to convince myself this a good value since it is the best of the best as far as HPA come. I can cross the HPA component off the list of getting in the way of my music. The way I am convincing myself of this is that it would also be an incredible pre-amp to accurately transport my DAC data to my power amp without coloration.

[@PassionforSound]

It's definitely an exceptional amp

[@vaneast411]

again another very interesting analysis between qualities present in different amps thx!

[@PassionforSound]

Glad you liked it!

[@tonynewman3631]

No love for the Holo Bliss KTE? I have found this amp to be an excellent mix of technical prowess with a touch of musicality. You can have both in one unit.

[@aceofspades6667]

He’s commented previously about trying to get a review unit from Holo in Auz is very challenging. The local distributor is not interested.

[@tonynewman3631]

@@aceofspades6667 That is unfortunate. I have been searching for a high end headamp that combines technical ability with some musicality for a long time. The Holo Bliss scratches that itch nicely for me. If you are after an amp that sits somewhere between the HM-1 and Enleum AMP-23R (technical ability vs musicality), at a price below both of them, then the Holo Bliss should be on your list. Golden Sound has an excellent review up on his site.

[@fatdoi003]

Golden sound is a Holo slut... I never seem him had any negative comment on any Holo gears..

[@PassionforSound]

Yep. Not a lack of interest - just access

[@tonynewman3631]

@@PassionforSound Pity the distributor isn't playing ball. It is an excellent amp. I love mine.

[@devenmajmudar839]

Great review Great amp. How would you compare it to T+A HA 200 headphone amp/dac ? Thanks

[@PassionforSound]

I haven't tried the T+A so I can't say - sorry

[@rustygates3367]

Probably my next move from the AMP-23R would be the Felix Audio Envy with Elrog 300B-Mo tubes (14,000 AUD deal from IndieHiFi as quoted). That's the same price as the HM1 in AU, but, I think it's going to be better than both the 23R and HM1 subjectively. I've got the Mola Mola Tambaqui DAC on order pending build & delivery too. I'll see how the pairing goes with the AMP-23R, then think if I'd like to explore the high-end tube scene. I did reach out to Zahl to see what the potential of getting a HM1 would be, if anytime soon, but I think given there is a production issue delaying '23 production run and so much demand you won't see one until at least the end of 2025. The lead time are somewhat pathetic tbh.

[@PassionforSound]

Wow! That's a bit crazy (the production delay). The Envy is a lovely amp so it will be a very interesting comparison.

[@jack4321able]

I am in the same boat. I have the ENLEUM 23R and love it. Have my eye now on a top tier tube or tube hybrid amp to get a greater more holographic sound stage from the Susvara. I am looking into Hifiman EF1000, Rivera A1C, Woo Audio Luna WA23 or upgraded Feliks Envy (e.g Elrogs)

[@PassionforSound]

Nice range of options!

[@jack4321able]

Have you auditioned the Feliks Envy yet. There are many rave reviews with amazing synergy with the Susvara. I was hoping to find a comparative review for the other $10,000 plus amp selections either pure tube or tube hybrids with Susvara but there are none. That’s why we all love your reviews.

[@PassionforSound]

I've tried it (I think) in show conditions only which is never ideal. I'd love to get one in for proper review one day.

[@sentientsteve9351]

I started watching this video and was thinking now you are just teasing us with unobtanium 🙂 but great to see the comparisons at the end because almost everyone would fall into the next tier down and it's nice to know there's only a percent or two in it. Now I'm just lamenting that I saw a phonitor x second hand last week and thought about it for 15 minutes and in that time it sold 😞

[@sentientsteve9351]

@@fisherman9435 there would be professionals who need the best for their work and probably the purchase is in a company name and tax deductible but there are also people in the world who just have buckets of money so 6k more for a 1% increase is worth it to them. Then there's the rest of us... Either way from what I understand there is a wait list of over a year if you want one of these units so the people making them are selling more than they are willing/capable to make.

[@PassionforSound]

Yes, this is a pro tool first and foremost, but there are also plenty of wealthy audiophiles who will be keen to get this amp. I recently sold a bunch of gear to make it possible to buy the Enleum AMP-23R, but don't feel like I'd do the same for the HM-1. I share that to partly point out that it's all about what captures our hearts, but also that I think the HM-1 might be a step too expensive unless you really need the features (i.e. pro usage)

[@kanegforce3974]

How does it compare to the T + A HA200 headphone amp? Is the sound quality more neutral on the Zähl HM-1?

[@PassionforSound]

I haven't tried the T+A to comment - sorry

[@invisiblekid99]

Would love to see this put up against the Mass Kobo 465 and see if $17K is worth it lol.

[@PassionforSound]

That would be a great battle!

[@asan1050]

Passion for Sound ThanksMuch!=

[@TriAmpHiFi]

I can't find headphone power amplifiers......................... All the head-amps I see available are integrated with preamps. I already have a nice preamp. Are there any power amplifiers out there? 🔈🔉🔊

[@PassionforSound]

The only one I've come across is the Burson Soloist 3XP which has a power amp mode to bypass the volume.

[@TriAmpHiFi]

@@PassionforSound Hey, that was very nice of you to thoughtfully respond. 😁

[@PassionforSound]

My pleasure. I try to reply to all comments where possible 🙂

[@random-internet-dude]

@@PassionforSound Ferrum's OOR can also be used as power amp. I wish there was more options but that's the only ones i'm aware of.

[@amaya897]

Would be interesting to her a detailed comparison with holo bliss

[@PassionforSound]

I'd love that too, but I can't currently get my hands on the Bliss.

[@Thiago_TS_BR]

I'm curious about Hifiman Goldenwave Serenade !

[@PassionforSound]

That does look pretty cool! I'll try to get one if I can, but for now I just received EF600, Audivina, Arya Organic and Ananda Nano so I've got lots to cover from them right now 🙂

[@Thiago_TS_BR]

@@PassionforSound Very interesting stuff ! Cant wait for the review about arya organic. Have they fixed the timber issue ?

[@PassionforSound]

I've only briefly listened to them, but my very early thoughts are that timbre has changed, but perhaps not been completely "fixed" in terms of sounding completely natural.

[@rogerhuston8287]

While I appreciate the HM-1s functionality, I didn't particularly enjoy the sound. I enjoy the Holo Bliss sound more at less than half the price, or the 465 on the high end.

[@PassionforSound]

Thanks for sharing your experiences.

[@Kyorakun]

Hey Lachlan, will you be reviewing the Holo Bliss KTE?

[@PassionforSound]

I don't currently have plans because the local supplier is a bit limited in demo stock availability ☹️

[@chipsnmydip]

I own an HM1 and had an AMP-23R. The HM1 has vastly more resolution, and the AMP-23R has a very narrow image. I dont use the HM1 controls much either, but you can approximate the AMP-23R with Class A mode and two clicks to the left on both the treble and stereo image control.

[@52092634]

how the sound compare to chord hugo tt2??

[@PassionforSound]

That's a great question. I didn't directly compare in terms of critical listening, but knowing the TT2 as well as I do and the other amps I also use with the TT2 as DAC, I'd say the HM-1 is one of the rare amps that not only maintains the transparency of the TT2, but might actually improve the overall sound quality at the same time because of the level of refinement and separation it brings to the sound

[@phantomplastics6582]

Nice work. Other reviews say that the Holo Bliss is as good but far cheaper.

[@PassionforSound]

I would be curious to test that claim, but getting Holo gear for review has proved a bit tricky since I didn't choose to rave about the Spring DAC ☹️

[@fatdoi003]

In essence the 3x GT v2 maybe the best bang for buck SS amp?

[@sentientsteve9351]

Depends on your headphones. I bought a Soloist 3XP thinking it could be a one and done SS amp but found out later that while it's great on low impedance headphones the synergy isn't there on high impedance cans. Seems some SS amps are designed to deliver current and others are designed to deliver voltage and the higher voltage delivery designs work better with high impedance headphones. I'm guessing the GT is similar design and best suits low impedance headphones.

[@fatdoi003]

@sentientsteve9351 think the power delivery is very different between 3x and 3x GT.... one uses 3A PSU and the other 5A

[@PassionforSound]

The 3XP and 3X GT (or 3 GT) are very different. They're built on the same foundational approach, but the GTs are significantly "more" in many ways. I do think the v2 GTs are an excellent endgame option without spending a super fortune, but there are still others I'm yet to try. As for high impedance headphones, I've found both the 3XP and GT models to do well with all impedance designs so I think any perceived lack of synergy is more about the tonality of the amp and how it pairs with the headphones and with your expectations. All amps deliver both voltage and current - it's what defines the power output of the amp into each load (voltage x current = power). Unfortunately, there's quite a bit of misunderstanding in the hobby about how amps and power work, but the synergy between headphones and amps are almost always about tonality, not power (OTL amps with high output impedance being the exception).

[@fatdoi003]

@@PassionforSound Lachlan, say for a 3xGT amp, what kind of DAC will you pair with for classical music... Delta sigma or R2R?

[@PassionforSound]

I would go straight for a Gustard R26 or a Chord Qutest/TT2 depending on budget. The Denafrips Pontus and Musician Pegasus are also good options, but I'd focus on the others first.

[@johenkay1129]

I'm starting to disagree with Goldensound a lot more. His taste is getting leaner and more analytical as time goes on, and I don't get it.

[@PassionforSound]

That's interesting to hear you say that. I'd been feeling a bit the same, but hadn't put words to what I was feeling. Amir Mk2? (Only kidding)

[@johenkay1129]

​@@PassionforSound Two Amir's could usher in a world where music is only made of numbers and graphs, a future where measurements reign supreme.. Enjoyment and emotional involvement replaced by the cold hard assurance of knowing everything measures perfectly. In this dystopian future using your ears is a crime, but a John Connor figure will emerge to fight the machines and bring humanity back to audio in all its "distorted" glory. (Just kidding... hopefully...)

[@PassionforSound]

🤣

[@aaronfriedman8201]

Do I feel like a loser after listening to this review? I have the new Gustard H26 Head amp and Aune SP17 Pro Headphone amp on the way. I am teaming them up with the Gustard A26 DAC for my Headphone listening. I thought my choices were reasonable. After listening about these pieces of equipment I am starting to feel that my choices are inadequte.

[@PassionforSound]

I'm pretty sure you'll love that setup when it all arrives. With those devices (AFAIK) you'll be reaching the level where the remaining gains to be had are incremental. The HM-1 is amazing, but it doesn't necessarily make listing to music more enjoyable and that's what matters most IMO.

[@adeadcrab]

the best kind of superior

[@PassionforSound]

LOL. Some would say the only kind 😉

[@ConvinceMeAudio]

Glad the review unit came to you too, 🐅 But as for most expensive headphone amplifier on the planet, not quite, I currently have Wells audios headtrip iii level ii on the desk, being reviewed right now, $17,000. Prices are just getting out of control LOL Hope you’re doing good bud

[@nicktan4530]

Because many rich people support these prices. Many of us left out of the water. Even $1000 is too expensive for us peasent.

[@fatdoi003]

people drive Toyotas, people drive Ferraris.... if there's a market for the product, people can spend their money how they like to

[@nicktan4530]

@@fatdoi003 sure. But we are talking about audio. At least Ferrari has difference in performance over Toyota

[@PassionforSound]

This has a difference in performance too, Nick. Just like a Ferrari vs Toyota, the HM-1 and a Topping L30 will both drive headphones well so you can enjoy music, but some people want more detail, resolution, better staging, etc. and that's what the HM-1 delivers.

[@fatdoi003]

@nicktan4530 i'm not sure what gears you are listening to so i don't really know how to reply you....

[@ZXZ-im5gn]

यह नियम!

[@techmed-rainer]

Danke!

[@PassionforSound]

Thank you, Rainer!

[@nitraM321]

Holo Bliss next ?

[@PassionforSound]

I'd love to, but can't get a demo unit ☹️

[@VirusForPrez]

I'll stick with my L30 for now , ....

[@PassionforSound]

🙂

[@frederf69]

pretty ok gadget but 8k no. good review as usual ✌😎👍

[@PassionforSound]

Thanks Fred. Too much for me too even though it sounds wonderful

[@nick_g]

Class A, all the way!

[@PassionforSound]

Yep, that's my preference too

[@palefaced1]

Apex Pinnacle costs more. As does woo Audio wa33 elite. And Viva. There are plenty that cost more.

[@Peace_Guard]

But I think he meant solid state.

[@fatdoi003]

Tube amp is like a blackhole chewing up cash... once started to tube roll esp NOS tubes, there's no turning back

[@InternetUser-d7s]

​@@Peace_GuardMass Kobo 465 costs 15k, it's a SS amp.

[@PassionforSound]

Yes, I didn't actually research the more expensive amps available. That's an error on my part - sorry!

[@Peace_Guard]

@@InternetUser-d7s Are there any comparisons with Bliss, Oor etc.? Hard to discuss without comparison data. A short search doesn't seem to find much.

[@InternetUser-d7s]

Not the most expensive at all. Mass Kobo 465, another SS, literally costs twice as much.

[@PassionforSound]

Yes, I didn't actually research that comment - my mistake

[@masterazlan6999]

1stly, sounded n looks like a studio equipment Ha2.. thought so Lots of emphasis towards music.. N dats studio stuff do.. Peace!

[@PassionforSound]

Yes, it's made more with professionals in mind

[@rogerhuston8287]

Nope, not the most expensive and there is, perhaps, a better and more limited headphone Amp. 465

[@PassionforSound]

Yes. I said that off the cuff with no research or extended thought 🙂

[@mariodrv]

Most expensive? Never heard of Woo Audio?

[@fatdoi003]

Maybe in solid state

[@PassionforSound]

No, just a lack of research on that particular detail. Sorry!

[@masterazlan6999]

N we as audiophiles makes it better.. Not in dis case.. Peace again!

[@chwb99]

It‘s Zähl, not Zahl. You should do him justice if he creates such a phenomenal device.

[@PassionforSound]

Sorry about that. I made sure to pronounce his name properly and respect the technical prowess in the design. Hopefully that's demonstrating the respect I have for him and his work.

[@neilsnyder7915]

This reviewer is costing me a fortune. I buy everything he loves……

[@MistaLova-Lova]

Thankfully not everything he loves is for sale 😁😉

[@PassionforSound]

This is true! I think you'll love the HM-1, Neil

[@frederf69]

@@PassionforSound 😅😅

[@aRc11-11]

Yeah, but money can't buy you love. ❤ Very garage build look, cheap knobs and questionable casework.

[@kajetan9550]

Money also can’t really buy you this amp cause it’s sold out. Have you held it in your hands? There are more expensive amps that people are buying like wa33 or Feliks envy

[@aRc11-11]

@@kajetan9550 More money 💰? Doesn't make anything necessarily better. People at head-funk love putting the window dressing in the signature. When music is just a tool for evaluation? You've lost the love of it. Entry level gear is so good today. Nothing is perfect and after a while, little bothersome niggles show up. Then gear has a for sale sign around its neck.

[@kajetan9550]

@@aRc11-11 just saying, cause it was stated in the video this is the most expensive headphone amp. It’s not. However it is very hard to get. It’s not about evaluating, once you experience something that makes you go ‘wow’ it’s hard to go back to sth that now makes you ‘meh’

[@aRc11-11]

@@kajetan9550 his "wow" didn't last that long. He preferred the traits of other amps before it was said and done. WOW's never last in the end.

[@kajetan9550]

@@aRc11-11 at which point did we speak about his impressions? Or my ‘wow’ did address hm1? i havent heard it. You touched on value and evaluating music instead of enjoying it, I mentioned how it usually works

[@SkywhiteChannel]

Once again this reviewer doesn’t know certain facts and runs with his own inaccurate assumptions. The cable between the power supply and the amp can be ordered at different lengths. Duh!

[@PassionforSound]

If you check the pinned comment, that was addressed before the video was publicly released.