[toaster]

Yes I agree different animal completely. At this level it comes down to personal preference.
4's sound more similar to the neutral sound of the U18t's

best

totally.

haven't heard the m4, so can't comment on it. the m5 is unabashedly v-shaped, and it sounds like the m4 is more neutral.

my current top 3, on equal ground, are the a18t / m5 / elysium.

 

[AlexanderBelonozhko]

The M5 uses a TIA for highs as well as an electrostat. It is inverted or something to make it work in custom tubeless.

For clarity, our M series Highs and TIA highs are not identical. Though the base driver itself is, TIA has a modified case exposing the diaphragm.

 

[Vitaly2017]

For clarity, our M series Highs and TIA highs are not identical. Though the base driver itself is, TIA has a modified case exposing the diaphragm.

Ohh I am very curious about your improved tech on the drivers. Would it be possible to tell us more? Please

How the drivers work what do they look like.
How are they able to play sound and being tubeless. While other companies never dared to be tubeless?

All this is very intriguing and fascinating. I do like 64a so I guess when I will hear Fir iem I will lose my mind haha.

 

[soLicitous]

I managed to pick up my demo kit before work today... spent 20-30 mins with each the M3, M4, and M5.

I started with the M3 and nearly just called it a day. They were so good to my ears. If I could describe my perfect sound signature I would have claimed it was the M3.

The M4 were noticeably more even in their tuning. They were clear, yet the sound didn't come off quite as large as the M3. I can see how people would prefer their tuning, it just wasn't quite what I was looking for at first listen. I will obviously spend more time with these over the weekend.

Lastly the M5... I don't even know where to start. I had read that the M5 were like the M3 on steroids and I'd have to agree. There was just a bit more of everything from the M3 in the M5. I don't know how to describe it other than everything was alive and clear - I didn't have to listen for anything, I just heard everything. Truly fantastic in my limited time with them. I'll have to go back and forth directly between the M3 and M5 to see if I can pinpoint exactly what I'm hearing.

Enough rambling... back to work for a few more hours.

 

[eldss]

As I said earlier in this thread, I was surprised to find the M4 closer to the Trio than the M3. I expected the opposite since the M3 and Trio are superficially similar.

My take is different than eldss'. I found the M4 bass to be elevated, in a good way, compared to the Trio. After having the HUGE bass of the M3 I wanted that back, but with better treble definition. I think the Trio extends just as deep, but, like my impression of the U12t, rumbles rather than hits. And, bass from the Trio is shelved down in level with respect to the mids and highs. It sounds natural if you expect your bass to be a supporting player, providing a foundation for the rest of the music, but the M4 brings the bass up to equal level with the rest of the instruments.

Treble through the Trio is beguiling in its delicacy and detail presentation. In contrast, highs from the M4 are energetic, dynamic and crystalline. Both are beautiful, but they are different. I Don't think Trio would ever be accused of "bright" or hot treble, maybe overly laid back. Conversely, perhaps some would find M4 treble analytical or aggressive.

I found the mids quite similar in my short time with the M4.

My take. I have some song references in the M4 review I posted here.

Now I'm wondering if I have one of the older tunings for the M4. I remember reading that there were several versions before they settled on a final tuning. I'm perfectly happy with what I have though. @AlexanderBelonozhko when was the current tuning finalized?

 

[chickenmcnug]

Now I'm wondering if I have one of the older tunings for the M4. I remember reading that there were several versions before they settled on a final tuning. I'm perfectly happy with what I have though. @AlexanderBelonozhko when was the current tuning finalized?

IIRC, around June/July of last year.

 

[arijitroy2]

Now I'm wondering if I have one of the older tunings for the M4. I remember reading that there were several versions before they settled on a final tuning. I'm perfectly happy with what I have though. @AlexanderBelonozhko when was the current tuning finalized?

The new tuning iem should have the bunny ear logo, older one had the FIR logo.

 

[AlexanderBelonozhko]

@Vitaly2017 Keeping the signature consistent with varying shell sizes in custom form is the main hurdle to fully tubeless customs. How we managed to mitigate the resonance & loss of compression(to a larger air volume) is by using a dampening material in the body of the shell. This reduces resonance by absorbing vibrations, as well as increases compression by displacing air volume.

@eldss Beginning August 2019 is when the final change took full effect. I posted a note earlier: https://www.head-fi.org/threads/fir...n-and-impressions.910581/page-3#post-15084050

 

[Vitaly2017]

@Vitaly2017 Keeping the signature consistent with varying shell sizes in custom form is the main hurdle to fully tubeless customs. How we managed to mitigate the resonance & loss of compression(to a larger air volume) is by using a dampening material in the body of the shell. This reduces resonance by absorbing vibrations, as well as increases compression by displacing air volume.

@eldss Beginning August 2019 is when the final change took full effect. I posted a note earlier: https://www.head-fi.org/threads/fir...n-and-impressions.910581/page-3#post-15084050

May I ask why 64a uses things like tia air chambers and tia bores?

While Fir audio simply goes all drivers are open inside the whole shell. Uses the shell it self as the unique and shared air chamber to all drivers. Does the small cables and components get in the way of the sound and affects it?

Also the other difference I saw is the frequencies response 64a is 5 to 22 000 and Fir is 10 to 20 000.
Would that mean Fir iem wont go as low in sub bass as the 64a?
I am talking specifically about tia trio or tia forte....

Thanks for your explanation it helps me to understand better the iem functionality

 

[bogdan belonozhko]

”May I ask why 64a uses things like tia air chambers and tia bores?“

This is a great question. It’s all about taking the cover off and exposing the diaphragm. Once the tia drivers are exposed you cannot filter them in any way. The chambers are used to essentially filter and shape the sound of that driver. Alex and I discovered with fir’s method of tubeless design, customs were possible. This gives us a huge advantage over the tia system. Also bear in mind the “tia” customs, only the high driver is tubeless, the rest of the drivers are still tubed.

 

[Vitaly2017]

”May I ask why 64a uses things like tia air chambers and tia bores?“

This is a great question. It’s all about taking the cover off and exposing the diaphragm. Once the tia drivers are exposed you cannot filter them in any way. The chambers are used to essentially filter and shape the sound of that driver. Alex and I discovered with fir’s method of tubeless design, customs were possible. This gives us a huge advantage over the tia system. Also bear in mind the “tia” customs, only the high driver is tubeless, the rest of the drivers are still tubed.

Wow thanks so much for a very detailed explanation!

That is indeed a big plus for Fir to have a driver that can be fully open and operate in a tubeless way...
We can say this is the true tubeless!

What about the frequencies response?
Does the 10 to 20k vs 5 to 22k means anything?

I really love when the music can go deep and low in sub regions. I specially rivalled a lot on fortes bass I wonder how is m4 or m5 dd is tuned? Is there any similarities? How did you tuned it can you please share some info

 

[John2e]

I wonder how is m4 or m5 dd is tuned? Is there any similarities? How did you tuned it can you please share some info

In 10 days or so you will be able provide an excellent analysis of the two. From our PM's, I have a feeling one of these guys will be perfect for you. I look forward to your analysis. Your patience is appreciated.

Best

John

 

[bogdan belonozhko]

The drivers aren’t open but they don’t have a tube attached to them. Want to make sure that’s clear that we don’t expose the diaphragm like tia.
22k no one can hear that high so it’s irrelevant. We use the same driver just not exposed so that spec is 20k on our site because again no one can hear up to 20k either. 10vs20 on the low driver, the drivers are very similar, we felt posting below 20 was not necessary either.

 

[mvvRAZ]

How high/low something goes ends up being pretty irrelevant anyhow since it's pretty much all about the FR and how lifted/recessed those regions are. Once you go into almost anything HiFi you'll find it covers the entire audible region, but whether you actually enjoy it is a function of how the tuning is done

 

[Vitaly2017]

The drivers aren’t open but they don’t have a tube attached to them. Want to make sure that’s clear that we don’t expose the diaphragm like tia.
22k no one can hear that high so it’s irrelevant. We use the same driver just not exposed so that spec is 20k on our site because again no one can hear up to 20k either. 10vs20 on the low driver, the drivers are very similar, we felt posting below 20 was not necessary either.

Aaa okey so is it correct of me to think that those ba and dd in fir shell are acting like a mini speakers system?

I remember I saw a video that you posted on Facebook about the tubeless design and the sound it made. It was said that tubeless bring the effect of an open back headphones sound like. Does that bring the issues that headphones have with resonance and some times some spikes on certain frequencies. Like hd800 is around 8k.