XXHighEnd - The Ultra HighEnd Audio Player
April 27, 2024, 08:52:56 am *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with username, password and session length
News: August 6, 2017 : Phasure Webshop open ! Go to the Shop
Search current board structure only !!  
   Home   Help Search Login Register  
Pages: [1]
  Print  
Author Topic: Analog signal levels  (Read 9906 times)
0 Members and 1 Guest are viewing this topic.
ivo
Audio Enthusiast
**
Offline Offline

Posts: 246


Music lover


View Profile WWW
« on: January 11, 2012, 09:42:40 am »

Hi folks,

I am not so knowledgeable in decibels and other stuff, so will you please help me out in understanding the specs of my DAC's analog input and output:

Line Input / Output

Type: Unbalanced RCA
Level: -10dBV Nominal (@-16dBFS) / +8dBV max
Impedance: 15kΩ(Input) / 200Ω(Output)


I want to understand what is the max value in volts (RMS) I can input into 'Line Input'?
Also, as the device acts also as pre-amp, I want to know what is the max value again in volts (RMS) to which it actually amplifies?
Can I input 2V (RMS) into such Line Input?


Thank you and below is the link to orig specs:
http://www.audiotrack.net/products/DRDAC2DX/spec/

Ivo
Logged

Music on internal HDD in FLAC-->LatestXX in QAP + PeakExt Mode[KS,Adaptive,2048,Q1=14,xQ1=1,Sch3,Low,Realtime,15 ms, SFS 2-400, Straight, stop all, MinOS]-->Windows 7 Pro SP1 x64bit-->Intel i5 based laptop [8 GB RAM]-->JKDAC32(HiFace based USB-I2S-DAC)-->Denon PMA-1500AE-->JBL E90 3-way speakers
CoenP
Audio Addict
***
Offline Offline

Posts: 818


View Profile
« Reply #1 on: January 11, 2012, 08:24:10 pm »

I don't know what dBV is referenced to but dBU is 0.775 Volt RMS (about 1 Volt peak). I take it that the spec is incorrectly edited or has been mistyped..
dBFS is full scale, so the nominal value is 16 dB below full scale, which is 10dBV below 1dBU. Iow maximum scale is 16-10 dB = +6dBU or 2x 0.775 V RMS (x0.70707 for Peak Voltage). Peak input would then be slightly more than 2 Volts.

On the output side the dac peaks at +8 dBU or 20x log( 8 ) x 0.775 Volt Rms (x0.70707 for the peak value). Any calculator can give you the answer to this :-).

[I edited above line so the log( 8 ) doesn't turn into log(Cool. - Peter]

Looks like a quite normal device to me.

Regards,  Coen
« Last Edit: January 12, 2012, 07:10:01 am by PeterSt » Logged

Settings: Qn: , SFS: , timeres: XT tweaks: , buf: 4096, driver: 8 ms,

Audio PC (jan 19): XXHE PC v1 with RAMdisk w.o. videocard and 1 of 2 cpu fans + BRIX/USB3 storage musicserver. ETN to Fibre converters (linear supplies), 500m SFP modules & 5m OM4 cable. Power cable PE not connected, together with nos1 and poweramp in separate "audio" powerstrip.

Clarixa set + Intona (or Lush 1m), Phasure NOS1a-75B G3 USB (buf 16 ms)-> Blaxius ->SE EL95 (0,8W triode) + cheap link to Abaqus 300W plateamps> Bastanis cable-> Bastanis Sagarmatha Duo ("DIY").

[other sources: TD124/3009SII-i/Grace F9/lounge LCR phono; Rega Planet 1997 vintage]
ivo
Audio Enthusiast
**
Offline Offline

Posts: 246


Music lover


View Profile WWW
« Reply #2 on: January 11, 2012, 08:49:11 pm »

Thanks Coen! It helps.

Ivo
Logged

Music on internal HDD in FLAC-->LatestXX in QAP + PeakExt Mode[KS,Adaptive,2048,Q1=14,xQ1=1,Sch3,Low,Realtime,15 ms, SFS 2-400, Straight, stop all, MinOS]-->Windows 7 Pro SP1 x64bit-->Intel i5 based laptop [8 GB RAM]-->JKDAC32(HiFace based USB-I2S-DAC)-->Denon PMA-1500AE-->JBL E90 3-way speakers
CoenP
Audio Addict
***
Offline Offline

Posts: 818


View Profile
« Reply #3 on: January 12, 2012, 09:27:56 pm »

Ok!
 i noticed a slight mistake. The peak value is of course 2X 0.70707 = 1.41414 the rms value (square root of 2).

Maybe i should try harder to quit listening to the nos1 late night  Wink and go to bed at a decent time. Man thats hard!

Regards, Coen
Logged

Settings: Qn: , SFS: , timeres: XT tweaks: , buf: 4096, driver: 8 ms,

Audio PC (jan 19): XXHE PC v1 with RAMdisk w.o. videocard and 1 of 2 cpu fans + BRIX/USB3 storage musicserver. ETN to Fibre converters (linear supplies), 500m SFP modules & 5m OM4 cable. Power cable PE not connected, together with nos1 and poweramp in separate "audio" powerstrip.

Clarixa set + Intona (or Lush 1m), Phasure NOS1a-75B G3 USB (buf 16 ms)-> Blaxius ->SE EL95 (0,8W triode) + cheap link to Abaqus 300W plateamps> Bastanis cable-> Bastanis Sagarmatha Duo ("DIY").

[other sources: TD124/3009SII-i/Grace F9/lounge LCR phono; Rega Planet 1997 vintage]
PeterSt
Administrator
High Grade Audiophile
*****
Offline Offline

Posts: 16837



View Profile Email
« Reply #4 on: January 13, 2012, 11:22:40 am »

Quote
i noticed a slight mistake. The peak value is of course 2X 0.70707 = 1.41414 the rms value (square root of 2).

Or ... or that is the Peak-Peak value. Haha.

Anyway, calculations are always performed with the 1.414, so this (p-p) is the comfortable one I think.

Peter
Logged

For the Stealth III LPS PC :
W10-14393.0 - July 17, 2021 (2.11)
XXHighEnd Mach III Stealth LPS PC -> Xeon Scalable 14/28 core with Hyperthreading On (set to 14/28 cores in BIOS and set to 10/20 cores via Boot Menu) @~660MHz, 48GB, Windows 10 Pro 64 bit build 14393.0 from RAM, music on LAN / Engine#4 Adaptive Mode / Q1/-/3/4/5 = 14/-/0/0/*1*/ Q1Factor = *4* / Dev.Buffer = 4096 / ClockRes = *10ms* / Memory = Straight Contiguous / Include Garbage Collect / SFS = *10.13*  (max 10.13) / not Invert / Phase Alignment Off / Playerprio = Low / ThreadPrio = Realtime / Scheme = Core 3-5 / Not Switch Processors during Playback = Off/ Playback Drive none (see OS from RAM) / UnAttended (Just Start) / Always Copy to XX Drive (see OS from RAM) / Stop Desktop, Remaining, WASAPI and W10 services / Use Remote Desktop / Keep LAN - Not Persist / WallPaper On / OSD Off (!) / Running Time Off / Minimize OS / XTweaks : Balanced Load = *62* / Nervous Rate = *1* / Cool when Idle = n.a / Provide Stable Power = 1 / Utilize Cores always = 1 / Time Performance Index = Optimal / Time Stability = Stable / Custom Filtering *Low* (16x) / Always Clear Proxy before Playback = On -> USB3 from MoBo -> Lush^3
A: W-Y-R-G, B: *W-G* USB 1m00 -> Phisolator 24/768 Phasure NOS1a/G3 75B (BNC Out) async USB DAC, Driver v1.0.4b (16ms) -> B'ASS Current Amplifier -> Blaxius*^2.5* A:B-G, B:B-G Interlink -> Orelo MKII Active Open Baffle Horn Speakers. ET^2 Ethernet from Mach III to Music Server PC (RDC Control).
Removed Switching Supplies from everywhere (also from the PC).

For a general PC :
W10-10586.0 - May 2016 (2.05+)
*XXHighEnd PC -> I7 3930k with Hyperthreading On (12 cores)* @~500MHz, 16GB, Windows 10 Pro 64 bit build 10586.0 from RAM, music on LAN / Engine#4 Adaptive Mode / Q1/-/3/4/5 = 14/-/1/1/1 / Q1Factor = 1 / Dev.Buffer = 4096 / ClockRes = 1ms / Memory = Straight Contiguous / Include Garbage Collect / SFS = 0.10  (max 60) / not Invert / Phase Alignment Off / Playerprio = Low / ThreadPrio = Realtime / Scheme = Core 3-5 / Not Switch Processors during Playback = Off/ Playback Drive none (see OS from RAM) / UnAttended (Just Start) / Always Copy to XX Drive (see OS from RAM) / All Services Off / Keep LAN - Not Persist / WallPaper On / OSD On / Running Time Off / Minimize OS / XTweaks : Balanced Load = *43* / Nervous Rate = 1 / Cool when Idle = 1 / Provide Stable Power = 1 / Utilize Cores always = 1 / Time Performance Index = *Optimal* / Time Stability = *Stable* / Custom Filter *Low* 705600 / -> USB3 *from MoBo* -> Clairixa USB 15cm -> Intona Isolator -> Clairixa USB 1m80 -> 24/768 Phasure NOS1a 75B (BNC Out) async USB DAC, Driver v1.0.4b (4ms) -> Blaxius BNC interlink *-> B'ASS Current Amplifier /w Level4 -> Blaxius Interlink* -> Orelo MKII Active Open Baffle Horn Speakers.
Removed Switching Supplies from everywhere.

Global Moderator
CoenP
Audio Addict
***
Offline Offline

Posts: 818


View Profile
« Reply #5 on: January 13, 2012, 04:59:09 pm »

Well,

Rms value is 0.70707 x the peak value of the sine or in reverse: peak is 1.4141 times the rms. So peak-peak would equate to +1.4141 - - 1.4141 = 2.8283 times the rms. p-p is not of interest when using a dac, rms and peak are all you need. (it can be handy in designing a dac though.)

Pffew,

I think I made it Happy!

Regards, Coen
Logged

Settings: Qn: , SFS: , timeres: XT tweaks: , buf: 4096, driver: 8 ms,

Audio PC (jan 19): XXHE PC v1 with RAMdisk w.o. videocard and 1 of 2 cpu fans + BRIX/USB3 storage musicserver. ETN to Fibre converters (linear supplies), 500m SFP modules & 5m OM4 cable. Power cable PE not connected, together with nos1 and poweramp in separate "audio" powerstrip.

Clarixa set + Intona (or Lush 1m), Phasure NOS1a-75B G3 USB (buf 16 ms)-> Blaxius ->SE EL95 (0,8W triode) + cheap link to Abaqus 300W plateamps> Bastanis cable-> Bastanis Sagarmatha Duo ("DIY").

[other sources: TD124/3009SII-i/Grace F9/lounge LCR phono; Rega Planet 1997 vintage]
PeterSt
Administrator
High Grade Audiophile
*****
Offline Offline

Posts: 16837



View Profile Email
« Reply #6 on: January 13, 2012, 05:41:14 pm »

Oh, but you already made it. Happy

But the mistakes are so easy to make (at least I have difficulties with it; somewhere another topic on the same floats around).

For a differentially setup DAC there's plus and minus voltage throughout. When the balanced output is 2VRMS the peak value of that is 2.828V (see the confusement coming ?). Well, if only plus is supposed to create that. But minus counts too. So, only half of that can do the trick, which is 1.414.

Can you still follow ? I already can't without real thinking, and this is because all the nice numbers (like 1.414) always end up like that. So I better grab my second beer; it helps me to forget ...

haha
Logged

For the Stealth III LPS PC :
W10-14393.0 - July 17, 2021 (2.11)
XXHighEnd Mach III Stealth LPS PC -> Xeon Scalable 14/28 core with Hyperthreading On (set to 14/28 cores in BIOS and set to 10/20 cores via Boot Menu) @~660MHz, 48GB, Windows 10 Pro 64 bit build 14393.0 from RAM, music on LAN / Engine#4 Adaptive Mode / Q1/-/3/4/5 = 14/-/0/0/*1*/ Q1Factor = *4* / Dev.Buffer = 4096 / ClockRes = *10ms* / Memory = Straight Contiguous / Include Garbage Collect / SFS = *10.13*  (max 10.13) / not Invert / Phase Alignment Off / Playerprio = Low / ThreadPrio = Realtime / Scheme = Core 3-5 / Not Switch Processors during Playback = Off/ Playback Drive none (see OS from RAM) / UnAttended (Just Start) / Always Copy to XX Drive (see OS from RAM) / Stop Desktop, Remaining, WASAPI and W10 services / Use Remote Desktop / Keep LAN - Not Persist / WallPaper On / OSD Off (!) / Running Time Off / Minimize OS / XTweaks : Balanced Load = *62* / Nervous Rate = *1* / Cool when Idle = n.a / Provide Stable Power = 1 / Utilize Cores always = 1 / Time Performance Index = Optimal / Time Stability = Stable / Custom Filtering *Low* (16x) / Always Clear Proxy before Playback = On -> USB3 from MoBo -> Lush^3
A: W-Y-R-G, B: *W-G* USB 1m00 -> Phisolator 24/768 Phasure NOS1a/G3 75B (BNC Out) async USB DAC, Driver v1.0.4b (16ms) -> B'ASS Current Amplifier -> Blaxius*^2.5* A:B-G, B:B-G Interlink -> Orelo MKII Active Open Baffle Horn Speakers. ET^2 Ethernet from Mach III to Music Server PC (RDC Control).
Removed Switching Supplies from everywhere (also from the PC).

For a general PC :
W10-10586.0 - May 2016 (2.05+)
*XXHighEnd PC -> I7 3930k with Hyperthreading On (12 cores)* @~500MHz, 16GB, Windows 10 Pro 64 bit build 10586.0 from RAM, music on LAN / Engine#4 Adaptive Mode / Q1/-/3/4/5 = 14/-/1/1/1 / Q1Factor = 1 / Dev.Buffer = 4096 / ClockRes = 1ms / Memory = Straight Contiguous / Include Garbage Collect / SFS = 0.10  (max 60) / not Invert / Phase Alignment Off / Playerprio = Low / ThreadPrio = Realtime / Scheme = Core 3-5 / Not Switch Processors during Playback = Off/ Playback Drive none (see OS from RAM) / UnAttended (Just Start) / Always Copy to XX Drive (see OS from RAM) / All Services Off / Keep LAN - Not Persist / WallPaper On / OSD On / Running Time Off / Minimize OS / XTweaks : Balanced Load = *43* / Nervous Rate = 1 / Cool when Idle = 1 / Provide Stable Power = 1 / Utilize Cores always = 1 / Time Performance Index = *Optimal* / Time Stability = *Stable* / Custom Filter *Low* 705600 / -> USB3 *from MoBo* -> Clairixa USB 15cm -> Intona Isolator -> Clairixa USB 1m80 -> 24/768 Phasure NOS1a 75B (BNC Out) async USB DAC, Driver v1.0.4b (4ms) -> Blaxius BNC interlink *-> B'ASS Current Amplifier /w Level4 -> Blaxius Interlink* -> Orelo MKII Active Open Baffle Horn Speakers.
Removed Switching Supplies from everywhere.

Global Moderator
Pages: [1]
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1 RC2 | SMF © 2001-2005, Lewis Media Valid XHTML 1.0! Valid CSS!
Page created in 0.066 seconds with 19 queries.