Zähl HM1 - Reference Headphone Amplifier

[nyev]

I just compared the HM1 running at the 110V setting vs 120V and found at 120V the sound had a little more dynamic and palpable bass.

Could totally be placebo but I don’t think so. I’d hope that if there was risk running at 120V that there would be official recommendations to run with the setting at 110V.

Too early to tell for sure but it sounds like @Frankie D and @QuantumQ may have experienced the same issue.

 

[nyev]

I initially had mine running at 120V with the old fuses (my HM-1 was from the 1st batch) but, once the fuse blew, it was DOA even with a fuse swap. Michael suggested the new fuse values and that I should be running in 110V. I’m so not an electrician but from what I can gather, dense cities (I’m in LA) are prone to variances; even with my clean power and EquiCore. Since I made the changes, it’s been solid and stellar.
I’m hoping for the best in your case that the turnaround time isn’t too bad, if you have to send it in.

Are you able to confirm the fuse values you are using now?

 

[Frankie D]

I initially had mine running at 120V with the old fuses (my HM-1 was from the 1st batch) but, once the fuse blew, it was DOA even with a fuse swap. Michael suggested the new fuse values and that I should be running in 110V. I’m so not an electrician but from what I can gather, dense cities (I’m in LA) are prone to variances; even with my clean power and EquiCore. Since I made the changes, it’s been solid and stellar.
I’m hoping for the best in your case that the turnaround time isn’t too bad, if you have to send it in.

Interesting. They should really ship it that way then when going to the US. Funny though how my Holo May and MK-465 had no issues and are on the same circuit ( all attached to a Puritan Power Conditioner ).

 

[Frankie D]

I just compared the HM1 running at the 110V setting vs 120V and found at 120V the sound had a little more dynamic and palpable bass.

Could totally be placebo but I don’t think so. I’d hope that if there was risk running at 120V that there would be official recommendations to run with the setting at 110V.

Too early to tell for sure but it sounds like @Frankie D and @QuantumQ may have experienced the same issue.

Thanks for the info. I think my issue and what @QuantumQ experienced might be different as the fuses in the power supply never blew. They look just as good as the new ones.

Headphones.com communicated with Zahl ( I let Chris from Zahl know as well ) and it will have to be shipped back to Germany. I’ll keep you all posted.

 

[QuantumQ]

Thanks for the info. I think my issue and what @QuantumQ experienced might be different as the fuses in the power supply never blew. They look just as good as the new ones.

Headphones.com communicated with Zahl ( I let Chris from Zahl know as well ) and it will have to be shipped back to Germany. I’ll keep you all posted.

Sorry to hear that, but I'm glad you're getting sorted out.

Are you able to confirm the fuse values you are using now?

Its been a while, but I'm pretty sure its these I'm running:

https://www.amazon.com/gp/product/B07Z2VDTCJ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Zero issues.
I should probably give some context since I have been woefully inactive on this thread; I use my HM-1 day in and day out for high and low volume mix checks, late night mixing duties, and it's been perfectly reliable. I describe it as the pinnacle of what pro audio should sound like (and used to, once upon a time). While a substantial part of my day revolves around multichannel/Atmos mixes, the HM-1 is most certainly the central hub to the 2 channel part to my studio.
When I really want to know what a mix, a master, a sound file or a headphone truly sounds like, I've literally found nothing better.

I also use it for listening pleasure as either standalone or as a pre for both of my tube amps (Aegis and Soul170HA) and my full range 3way stereo mains.

 

[Frankie D]

Hi All. I wanted to keep you all posted on the status of the repair of my HM-1. Michael Zahl got back to me directly ( which I do appreciate) and the problem is fixed. Excellent service and a very fast solution. It will now be shipped back to me. Headphones.com was also excellent.

Michael Zahl said the issue was not the fuses or fuse box, but with the “power inlet assembly.” The whole power inlet assembly has been replaced which does include the fuse block, though the fuse block was not the issue. There was a faulty internal connection.

Michael said he was amazed as Schurter , who makes the assembly, is known for their high quality standards. He did say he will follow up with them.

I will be happy to have it back!

 

[Roasty]

the new power supply unit arrived. anyone wanna play spot the difference? the newer unit is below.

looks like some minor changes to wording placement. the serial number badge on the newer unit comes on a dedicated metal plaque. and the front and rear fascia are just a tad darker.

when placed together with the main HM1 box, the old power supply box matches colour/shade better.

 

[BassicScience]

the new power supply unit arrived. anyone wanna play spot the difference? the newer unit is below.



looks like some minor changes to wording placement. the serial number badge on the newer unit comes on a dedicated metal plaque. and the front and rear fascia are just a tad darker.

when placed together with the main HM1 box, the old power supply box matches colour/shade better.

The most interesting thing is that when you turn the units around, the wall phone turns into a vase of flowers. Neat trick!

 

[QuantumQ]

The most interesting thing is that when you turn the units around, the wall phone turns into a vase of flowers. Neat trick!

 

[Philex]

I have been thinking about buying the 1995 Immanis from Raal to pair my HM1, is there anyone tried this combination before?

 

[Hiker816]

I have been thinking about buying the 1995 Immanis from Raal to pair my HM1, is there anyone tried this combination before?

I have, and it's great! Feel free to check out my Immanis review for my take and comparison to other amps.

 

[Roasty]

I have been thinking about buying the 1995 Immanis from Raal to pair my HM1, is there anyone tried this combination before?

same as @Hiker816. it's an amazing combo and my daily driver right now.

 

[Philex]

same as @Hiker816. it's an amazing combo and my daily driver right now.

Good to hear your thoughts! I might plan to make my purchase in the next couple of months, and I will consider whether I need to buy the interface or not.

 

[Hiker816]

Good to hear your thoughts! I might plan to make my purchase in the next couple of months, and I will consider whether I need to buy the interface or not.

With most amps, including the HM1, you would need the interface (unless you already have one).

 

[Aetherhole]

I have been thinking about buying the 1995 Immanis from Raal to pair my HM1, is there anyone tried this combination before?

I know Hiker and Roasty already chimed in, but just supporting their responses… it’s a great pairing. I’ve heard it several times and it does very well!