Mavis Prima MPA-81s is a very nice donor mic platform

[kingkorg]

It seems cryo-treating audio gear is not new audio foolery concept after all. It's just that somehow I was lucky enough not to encounter it until now.

If it's not measurable, yet as much as 5% audible, I can't adress it at this point. This goes beyond my understanding of the world we live in. I am still getting one of these mics sooner or later to test terrestrial aspects of these microphones. Just by looking at pictures, I see several issues in the construction.

Marvelous post by CTP Cryogenics on their IG page where they occasionally, between treatment of camshafts, brake discs, do some tubes. Love the marketing plot under the image.

Then, there are HEALTHY people who want their brains frozen, so....

While wasting whole day on this new concept I found that ChatGPT summarized it much better than i ever could.


Cryogenic treatment, often referred to as cryo treatment, involves cooling materials to extremely low temperatures (usually below -300°F or -150°C) to alter their microstructure and potentially improve their properties. Companies like CTP Cryogenics claim that such treatments can enhance the performance of audio equipment by reducing internal stresses, improving conductivity, and enhancing durability.

### Claims and Support

1. **Improved Conductivity:** Proponents argue that cryo treatment can realign the molecular structure of metals, reducing resistivity and improving electrical conductivity. For audio equipment, this theoretically translates to better signal transmission and improved sound quality.

2. **Durability:** Cryogenic treatment is also claimed to enhance the durability of materials by relieving internal stresses and making the structure more uniform.

3. **Sound Quality:** Some audiophiles and manufacturers report subjective improvements in sound quality, including clarity, detail, and overall musicality after cryo treatment.

### Controversy and Criticism

1. **Scientific Evidence:** The scientific community is divided on the effectiveness of cryo treatment for audio equipment. While some studies suggest potential benefits in terms of material properties, there is limited empirical evidence directly linking cryo treatment to significant improvements in audio performance.

2. **Subjectivity:** Improvements in sound quality are often subjective and can be influenced by a placebo effect. Audiophiles' perceptions can be affected by their expectations and biases.

3. **Skepticism:** Many audio engineers and skeptics argue that the claimed benefits of cryo treatment for audio equipment are exaggerated and not supported by rigorous scientific testing. They contend that any improvements are likely marginal and not easily perceptible in typical listening conditions.


### Conclusion

While there is some theoretical basis for cryo treatment potentially improving the properties of audio equipment, the evidence supporting significant audio performance enhancements is limited and often anecdotal. The controversy mainly revolves around the subjective nature of perceived sound improvements and the lack of rigorous scientific validation. If considering CTP Cryogenics, it is advisable to research customer reviews and industry feedback to gauge the company's trustworthiness and the potential value of their services.

 

[Khron]

Marvelous post by CTP Cryogenics in their IG post where they occasionally between treatment of camshafts, brake discs do some tubes. Love the marketing plot under the image.

I particularly appreciate their putting "noise" in quote marks

 

[Voyager10]

OK, neither the Vanguard or Mavis mics in the original post are tube mics, and don't claim to have anything cryogenically treated.

Fascinating though it is, can I please ask that we keep on topic, or start a new thread?

 

[Paul W]

OK, neither the Vanguard or Mavis mics in the original post are tube mics, and don't claim to have anything cryogenically treated.

Fascinating though it is, can I please ask that we keep on topic, or start a new thread?

Apparently Vanguard does claim to cryogenically treat microphone components and that it improves them. @Wordsushi's new Vanguard V4 video credulously repeats stuff he was told by Derek from Vanguard which seems a whole lot like marketing BS.

 

[MicMaven]

3. **Skepticism:** Many audio engineers and skeptics argue that the claimed benefits of cryo treatment for audio equipment are exaggerated and not supported by rigorous scientific testing.

Yep. I once left my favorite headphones overnight in a car on a very cold (-15 F/-26 C) night, and they were ruined. I have seen the deleterious effects on guitars left overnight in very cold cars - they never play or sound the same afterward.

Nevertheless, I am fairly certain freezing WILL improve the flow of electrons in my 2 AWG four-foot long $400 OFC audio cables with $150 gold sputtered AC plugs and special Dacron weave insulation ... well, at least after they thaw out.)

So, count me among the skeptics.

[He typed donning his magnetic wrist bracelet, and soaking his charcoal infused insoles with WD-40 to detoxify his liver, improve circulation and minimize arthritis pain, while rubbing his favorite rabbit's foot, and anointing himself with snake oil.]

Anonymous

 

[damien]

I live in Canada, we don't need cryogenic treatment here. Music sounds better up north

I wonder if those 100MOhms and higher values (1 GOhms) thick films resistors have an impact on the sound, because when you buy them from Ohmite at mouser they are like 7$ each which is almost half the price of cheap chinese condenser microphones.

 

[Khron]

I wonder if those 100MOhms and higher values (1 GOhms) thick films resistors have an impact on the sound, because when you buy them from Ohmite at mouser they are like 7$ each which is almost half the price of cheap chinese condenser microphones.

Probably not. But those $7 ones are also waaaaaaay higher-power than you'll ever need in a mic. I'm partial to the TE Connectivity RGP0207 series (sub-$1 a piece).

 

[mmadu]

On the one hand, I'm glad there is a pretty nice donor body available. On the other hand, I'm sad that the Vanguard design is not protected in any way. Those shops in China don't have any regard for any intelectual properties. Zero ethics. It pisses me off. I own a couple Vanguard mics and use the V44S Mk2 all the time on drum room.

I admit this for some well-known manufacturers' products (such as Neumann or Sennheiser), but for manufacturers such as Peluso/Avantone or Advanced Audio, this statement seems biased - their income seems insufficient to support them having their own production lines and design teams. Given China's low labor costs and mature industrial system, the relationship between these products seems worth exploring.

 

[McIrish]

I'm not sure I follow exactly what you are saying.
I read through this thread again and was hoping Derek would have posted again but I fear the hostility got a little too high. It's a shame. I appreciated the fact that he came here in the first place. I'm not a an expert and the Vanguard marketing may be a bit over the top, but I do own a couple of their mics and have found them to be very useful. As I stated before, the V44S is my drum room mic in Blumlien. I've found the V13 is great on cello. I bought it for vocals, but it's never won a shootout on voice. It does shine on cello though. On the other hand, my Flat47 capsule has never won a vocal shootout either. I'd love if KingKorg was able to get one of the Vanguard mics and run some tests. That would be great.

 

[mmadu]

In fact, for a startup enterprise interested in the microphone manufacturing industry, a more common practice is to order some pre designed products from Chinese microphone manufacturers and only make some color modifications (such as most of Avatone's microphone products). Although after a period of sales, they usually hire designers to make minor modifications (such as replacing capacitors) to these microphones from China, Chinese manufacturers still have the original version of their microphones, and the exterior design and color matching cannot be protected by copyright laws. Therefore, these unmodified original microphones will appear on eBay or Alibaba, and they usually have only minor differences from the versions sold by distributors (such as cheaper diaphragms or cheaper capacitors), It doesn't sound like there's a significant difference. So if you're short of money, buy it.

 

[FxStudio]

I got a Mavis Prima MPA-81S and bought the Ariane K47 Flat - but with both capsules I am getting a ton of noise floor from the mic. Its a continuous ...Sssshh... sound all the time. I swapped my line to a Rode M1 and it performs just fine with the cable and SSL2+ MK2 USB interface. So I assume its something to do with the Chinese circuit boards in the Mavis Prima. Should I resolder the PCB's again or is it more likely to be a component, any ideas what it might be?

​

 

[Voyager10]

One of the earlier posts had a picture of a poor solder joint on this mic. It's certainly worth inspecting and re-making any joints which aren't good and shiny, then cleaning everything thoroughly (particularly around the capsule connections).

 

[FxStudio]

One of the earlier posts had a picture of a poor solder joint on this mic. It's certainly worth inspecting and re-making any joints which aren't good and shiny, then cleaning everything thoroughly (particularly around the capsule connections).

Thanks, and I also wonder about the capacitors, they say WIMA but they look a bit odd to me.
Like they could be fakes or something?
But I am only familiar with the Wima FKP range so I could be wrong.

 

[VanguardAudioLabs]

Thanks, and I also wonder about the capacitors, they say WIMA but they look a bit odd to me.
Like they could be fakes or something?
But I am only familiar with the Wima FKP range so I could be wrong.

replace them with MKP, and yeah they're likely fake on this board. We always bought the vast majority of our own components before PCB assembly.

bad 2N5551 transistors in the DC-DC converter circuit or rolloff can cause noise problems.

Also check that the 6.8V and 12V diodes are properly working.

What JFET are they using?

In a schoeps-style circuit i usually check the active components first.

A simple signal probe built from a guitar cable and a capacitor is super useful for diagnosis.

 

[FxStudio]

replace them with MKP, and yeah they're likely fake on this board. We always bought the vast majority of our own components before PCB assembly.

bad 2N5551 transistors in the DC-DC converter circuit or rolloff can cause noise problems.

Also check that the 6.8V and 12V diodes are properly working.

What JFET are they using?

In a schoeps-style circuit i usually check the active components first.

A simple signal probe built from a guitar cable and a capacitor is super useful for diagnosis.

Many thanks for the feedback.

On closer inspection 5 of the solder joints weren't made at all !!
No solder on them, just the components wire pushed through - so surprising it was even working.
I assume these boards are being hand soldered because a wave solder machine wouldn't be expected to miss so many joints.

The rest of the joints all look like bad/ dry-joints and had to be remade, with the difficulty of removing the old solder (wick and flushing it out).
Honestly, it would have been quicker if they gave me a bare board and a bag of parts.

They are using JC5551 in the DC-DC convertor - Japan Radio part (but lots of JRC stuff gets copied as well in China).
The JFET is a LS170F (Toshiba)
And the other 2 are 2N5087 a BJT (Bipolar Junction Transistors)

Wima's close up looking more sketchy as to their origin.

Question: which of the two 3-way switches is which function on the PCB's?
Would have been nice to have that on the ident so as to be able to assemble the cover the correct way round - seeing as it can fit both ways.

 

[VanguardAudioLabs]

Rear should be pad rolloff and front should be cardioid

Linear systems LSK170B, proper WIMA MKPs will be a nice audible upgrade. Although undoubtedly the capsule will make the most difference. I’ve always been baffled by the insistence on the MKS Mylar caps. Audibly, I find the Mylar WIMA MKS to be among the worst Mylar caps I’ve tried. I’d rather have a generic chiclet polyester cap than the MKS. One man’s opinion though.

We used mostly MKP2 in the gen1 for size consideration, but managed to squeeze MKP4s and 10s in the signal path for the gen2 with the upsized body and board.

You said they’re FKP copies but FKPs would be ginormous. I’d suspect they’re MKS copies. White or silver text on a red body, likely with red epoxy on the bottom.

We did spec the 2N5087. Tried a number of BJTs during dev and quite liked the way the 5087s. So not surprising they copied that too.

It’s clearly a copy of the board layout I made with some modifications, but we used a dedicated PCB assembler who did good soldering - Although we did have to chide them for cutting the leads almost 4mm long several times.

 

[FxStudio]

Rear should be pad rolloff and front should be cardioid

You said they’re FKP copies but FKPs would be ginormous. I’d suspect they’re MKS copies. White or silver text on a red body, likely with red epoxy on the bottom.

Looks like its a complete copy of your earlier board but just badly assembled.

I only got it for occasional use for recording the sound of my PA system in my studio/club.
If someone was going to make their living from it better to get the original IMHO.

Yes FKP's are huge - that's the only Wima caps that I am familiar with, I've never used the rest of their range.

So which PCB has which function on it?
Does the DC-DC board's 3-way switch control the rolloff, and the amp board control the cardioid ? or is it the other way round. I am sure its obvious to you mic guys but I haven got a clue when it comes to mics.

 

[VanguardAudioLabs]

Looks like its a complete copy of your earlier board but just badly assembled.

I only got it for occasional use for recording the sound of my PA system in my studio/club.
If someone was going to make their living from it better to get the original IMHO.

Yes FKP's are huge - that's the only Wima caps that I am familiar with, I've never used the rest of their range.

So which PCB has which function on it?
Does the DC-DC board's 3-way switch control the rolloff, and the amp board control the cardioid ? or is it the other way round. I am sure its obvious to you mic guys but I haven got a clue when it comes to mics.

Not quite the same. i mentioned earlier some of the changes, specifically the inductor layout. Using side-by-side inductors with proper field alignment and adjusting the distance between inductors with a plastic spudger can fine-tune the capsule polarization voltage without the need for a trimmer.

Bottom of rear board is DC-DC converter + CW voltage multiplier circuit, top is the rolloff/pad control. The front board is mostly signal path although there's power path elements to it as well.

On the gen2 I was able to consolidate a lot of that onto one board with the extra real estate.