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On 5/3/2018 at 12:59 AM, IronFilm said:

When the limiter of the F8/F8n is activated for a channel it automatically cuts 10 dB of gain from the analog preamp. That 10 dB is automatically added back after the AD converter. This is a way we build an extra 10 dB of headroom to avoid clipping over the already high dynamic range (A/D Converter has 120 dB dynamic range, with limiter effective dynamic range is 130 dB

In the past I tested the Limiter of the F4 (which should be the same as on the F8) and the dynamic range did not increase when the limiter was engaged. As expected, it merely shifts the dynamic range upwards a bit. Depending on the gain setting you do get at least 10db more headroom but of course the noise floor of the ADC also rises by 10dB. So, overall the dynamic range stays the same.

 

At 2:55 you can see the noise measurements if you are interested:

 

 

That said, an ADC with 120dB dynamic range is already very good and will be sufficient for the most recording situations.

 

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16 hours ago, chrismedr said:

sure, if you apply 10dB attenuation to your 130dB scream then it will record fine at 120dB, but at the same time everything that happened in the 1-10dB range is pushed below 0dB and therefore lost forever - applying digital gain will not bring back up any signal that was never sampled to start with. in other words a 10dB attenuation would allow for higher max levels, but not for higher dynamic range because you essentially just shift which 120dB you're recording.

 

 

That is not how -10dB works. 
 

These are logarithmic changes applied, not linear. So that doesn't mean you're left with nothing at all. It is just a weaker signal, not a non-existent signal that is "lost forever". 
 

6 hours ago, JayKay said:

Depending on the gain setting you do get at least 10db more headroom but of course the noise floor of the ADC also rises by 10dB. So, overall the dynamic range stays the same.


But on this point I'm inclined to agree, if the signal becomes so weak it is near the level of the noise floor then it can indeed become "lost". 

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21 minutes ago, IronFilm said:

That is not how -10dB works. 
These are logarithmic changes applied, not linear. So that doesn't mean you're left with nothing at all. It is just a weaker signal, not a non-existent signal that is "lost forever". 

 

well, true as long as we live in a logarithmic world and would sample at ultra high bit depth and avoid all noise issues of electronic circuits. that's not how recorders work though.

 

if the 120dB in the ADC is correct we can assume a 20bit ADC - which means a bit over 1'000'000 values to store the loudest to the quietest sound. afaik all commonly used ADC work in linear domain, that means the top 6dB (120dB to 114dB) will get about 500'000 code values (1048575-524288), while the quietest sounds (0dB-6dB) will get exactly 2 code values (0-1).

 

I simply can't see a way how you would recover 10dB more squeezed into these two code values.

chris

 

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Was really hoping they'd change the buttons where the writing rubs off/fades and the painted blue strap bars that chip and flake (why not use that lovely anodised blue metal you have on top and bottom?). Only cosmetic issues but I experienced both after only a few weeks of use.

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The half of the word "menu" is worn off on my Zoom F4, but otherwise I'd say it is holding up very well from constant regular usage. 

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What I would hope for (or possibly 'would have hoped for'?) on an update of the F8 would principally be a digital I/O (AESEBU preferably or SPDIF or both) and a cascade link to sync and operate two or more of them together. (A digi IO would of course enable it to be synched easily to another suitably equipped machine, and for many of 'us' pro sound users that might be our 'A' recorder, like a SD 7 series or whatever).

 

The only other obvious updates would be open mic/line selection between the XLR and TRS inputs, a choice of pro and consumer line for the inputs and ditto for the outputs.

 

Oddly, in this era of the Zoom 4/8 and the MixPre 3/6/10, grabbing a cheap second hand Tascam DR680 as a synchable B recorder begins to look tempting for cheap (occasional) high track counts ... bring in the digital sync please Zoom!

 

Jez

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4 minutes ago, The Immoral Mr Teas said:

What I would hope for (or possibly 'would have hoped for'?) on an update of the F8 would principally be a digital I/O (AESEBU preferably or SPDIF or both) and a cascade link to sync and operate two or more of them together. (A digi IO would of course enable it to be synched easily to another suitably equipped machine, and for many of 'us' pro sound users that might be our 'A' recorder, like a SD 7 series or whatever).

 

Oddly, in this era of the Zoom 4/8 and the MixPre 3/6/10, grabbing a cheap second hand Tascam DR680 as a synchable B recorder begins to look tempting for cheap (occasional) high track counts ... bring in the digital sync please Zoom!

 

Oh! Good point there (I used to have 2x DR680 that I could run together). I should add that to my blog post. 
Certainly many people are already picking up an F8/F4 as a secondary extra recorder, and this feature would make it even more useful for that purpose. 

 

 

5 minutes ago, The Immoral Mr Teas said:

The only other obvious updates would be open mic/line selection between the XLR and TRS inputs, a choice of pro and consumer line for the inputs and ditto for the outputs.


Yup, most of that Zoom has said they're already implementing for the F8n. 

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