[triod750]

One day I am going to ask the owner if I can bring my own gear to play on them

Excellent idea that you eventually might regret.

 

[bcowen]

Here is a look at the final layout for the ZMF 45 amp. Final dimensions are 16.5" L x 13.5" W x 4.25" H.

Lundahl mains and filament transformers will be in the back, output transformers in the center. Potentiometers for bias adjustment in the front (left and right holes). Hole on the bottom right near the front is the output impedance switch for 300ohm, 120ohm, 32ohm output taps. The interstage transformers will be on the interior, along with five separate regulated power supplies (B+, bias, DC heater, 2x filament). The left and right channels each have their own dedicated B+ and bias supply regulators.



I've shown the front panel layout before, but here it is one more time. Volume knob center, bias milliammeters on left and right, TRS jack on the far right, RCA inputs on the far left.



Since ZMF headphones tend to have warm tones, to accent them well we are going across the color wheel, it will be coated in Distant Blue.



This color reminds me of vintage JBL speaker baffles. Got the stamp of approval from the ZMF crew.



I will go through the whole layout at least one more time to be sure all is sound, then will place the order along with anthracite gray Airmid chassis. Should have this 45 amp done in maybe 2-3 weeks.

Love the color! Zach should provide you with some wood side caps to really dress it to the nines. Your amp, his wood....the stuff dreams are made of.

Bargain basement representation below, but gets across the basic thought:

This wood is totally drop-dead gorgeous and would complement the blue nicely:

 

[L0rdGwyn]

Excellent idea that you eventually might regret.

Yeah I probably would! But it's okay, a lot of prerequisites need to be met before gigantic speakers enter my home lol.

Love the color! Zach should provide you with some wood side caps to really dress it to the nines. Your amp, his wood....the stuff dreams are made of.

Bargain basement representation below, but gets across the basic thought:



This wood is totally drop-dead gorgeous and would complement the blue nicely:

I'll probably pick up woodworking at some point, then maybe I can add some wood vibes to my designs!

 

[triod750]

Even now I can add some good vibes to my designs!

FTFY

 

[Xcalibur255]

You could just include standoffs on the sides of the chassis so he could add a wood flair from his own stock to personalize the amp.

 

[L0rdGwyn]

Yeah the wood side panel is something that needs special planning to be done well IMO. Ideally the top plate would be perfectly flush with the wood panel, at least the way I envision it, and there are components that need to be mounted on the side panel, would not want hardware visible externally on the wood, so would use a metal interior panel with screw holes counterbored to use flat head hardware such that the wood panel is flush when mounted to the side. So the chassis would need to be made specifically for that purpose and tolerances on the wood components would be small to get the sleek, flush result, which is challenging without the ability to cut the wood to size and alter it if necessary. I have a big garage overhaul project on the horizon, after which I might take the plunge / investment into woodworking equipment, could then incorporate it into chassis designs.

 

[Monsterzero]

Ideally the top plate would be perfectly flush with the wood panel,

There's something about a non-flush wood case that adds a vintage appeal IMHO

 

[triod750]

Yeah the wood side panel is something that needs special planning to be done well IMO. Ideally the top plate would be perfectly flush with the wood panel, at least the way I envision it, and there are components that need to be mounted on the side panel, would not want hardware visible externally on the wood, so would use a metal interior panel with screw holes counterbored to use flat head hardware such that the wood panel is flush when mounted to the side. So the chassis would need to be made specifically for that purpose and tolerances on the wood components would be small to get the sleek, flush result, which is challenging without the ability to cut the wood to size and alter it if necessary. I have a big garage overhaul project on the horizon, after which I might take the plunge / investment into woodworking equipment, could then incorporate it into chassis designs.

No KISS for you then?

 

[L0rdGwyn]

No KISS for you then?

No! Everything must be convoluted, expensive, and time-consuming.

 

[bcowen]

No! Everything must be convoluted, expensive, and time-consuming.

ROFL! My boss would agree with you to the letter.

I was thinking something along these lines. The inserts go into the wood, and the screws would go out from the inside of the side panels to fasten it. Probably overly simplistic, but once I leave work I always want things simpler than they have to be.

 

[Xcalibur255]

No! Everything must be convoluted, expensive, and time-consuming.

Could I interest you in any number of corporate middle-management positions sir?

 

[whirlwind]

Here is a look at the final layout for the ZMF 45 amp. Final dimensions are 16.5" L x 13.5" W x 4.25" H.

Lundahl mains and filament transformers will be in the back, output transformers in the center. Potentiometers for bias adjustment in the front (left and right holes). Hole on the bottom right near the front is the output impedance switch for 300ohm, 120ohm, 32ohm output taps. The interstage transformers will be on the interior, along with five separate regulated power supplies (B+, bias, DC heater, 2x filament). The left and right channels each have their own dedicated B+ and bias supply regulators.



I've shown the front panel layout before, but here it is one more time. Volume knob center, bias milliammeters on left and right, TRS jack on the far right, RCA inputs on the far left.



Since ZMF headphones tend to have warm tones, to accent them well we are going across the color wheel, it will be coated in Distant Blue.



This color reminds me of vintage JBL speaker baffles. Got the stamp of approval from the ZMF crew.



I will go through the whole layout at least one more time to be sure all is sound, then will place the order along with anthracite gray Airmid chassis. Should have this 45 amp done in maybe 2-3 weeks.

That distant blue may be my favorite color yet, blue but not too blue.....will it be matte finish or glossy...I am a sucker for matte finish.

 

[L0rdGwyn]

That distant blue may be my favorite color yet, blue but not too blue.....will it be matte finish or glossy...I am a sucker for matte finish.

It will be a gloss. Matte powders aren't offered very many places, the options are very limited unfortunately.

 

[Galapac]

It will be a gloss. Matte powders aren't offered very many places, the options are very limited unfortunately.

That’s True. I tried to find a company around here that works with Prismacolors powder coats because they have some really cool metallic powder coats but no such luck. They are a 2 step process and the main guys don’t want to touch them.

 

[L0rdGwyn]

Well I might have to amend my previous statements on the Audial S5 vs. my PCM56 DAC.

I said I was going to try the comparison again with a different amp. For clarity, detail, soundstage, imaging, etc., the 45 amp for Zach / ZMF is the best I have, so I brought both DACs to my workbench.



I came away with a completely different set of observations. Was it burn in of my DAC? Was it the final changes I made to the circuit? Or the amp pairing?

It was clear to me comparing the two that the PCM56 DAC has the larger soundstage, slightly better clarity, and better imaging. The "warmth" I heard on my 6A5G amp was gone. The sound is more three-dimensional with better vertical staging over the S5, which is itself no slouch. With this pairing, the PCM56 DAC seems to have a more forward / pronounced midrange as well, whereas the S5 is more even across the spectrum, at least that is my initial impression. Again, for technical performance, the S5 is close, but the PCM56 won out in this setup.

I will say this though - the pairing of the Audial S5 with the 45 amp is a little more relaxed and perhaps easier for a long listening session. The combination of the PCM56 DAC with the 45 amp is insane. The midrange clarity, imaging, soundstage...the detail retrieval is so high that it demands your attention. The pairing will pick apart a recording too - you can hear every minute detail. Another one of those cliché "I heard things I've never heard before" type of things. An example - on the electronic album Proto by Holly Herndon (which I was listening to this morning), on the track "Frontier" which is a mostly choral track with Gregorian-chant-esque vocals, between the first and second vocal sections of the track, the noise floor of the recording "cuts out", which made clear to me that the two sections were recorded separately and spliced together in production as opposed to being recorded in a single continuous take. I had never heard the noise floor of the recording so clearly, having listened to this track numerous times. The movement and breath and vocal detail in the opening section of the track "Extreme Love", along with the definition of the following bass line, was also pretty mind blowing.

I'll have to try the DAC comparison again with my 6A5G amp to see if my DAC has undergone some change or if it is pairing dependent, perhaps the 6A5G is imparting more of its sound on when paired with the PCM56 DAC. The 45 amp is the most technically impressive one I have, so seems it would get closer to the "truth" of the upstream gear.

So I guess in summary, I'm again very happy with how my PCM56 DAC turned out. I sought out a massive amount of NOS DAC design information and made what I felt were sound engineering decisions, but I still did not expect a result this good. And I cannot wait for someone else to lay ears on this 45 amp and confirm or deny my impressions, not too much longer.