My Pre Out Voltage Predicament. What’s your $0.02?

[dumple 5,000+ posts]

I remember when HU's had 200mv output on the RCA's.

When dinosaurs roamed the planet lol

 

[-DOZER-]

I think there is notable quality difference. A decent deck with a good dc/dc converter and 24bit dac will outperform 99% of the ones with crappier dacs and lower preouts. they usually go hand in hand. amping a smaller signal results in more distortion. a line driver will help but i would just suggest a better deck or an audio control eq. dont compromise sq for bells and whistles

Also bryan can attest that having the higher volts does help just in going from 4 to 6.5

Thanks, you hit the nail on the head. This was the kind of advice I was looking for. I agree 100% about the bells and whistles, but I just cant spend any coin on a new HU right now. The audio control EQ's seems to be a better alternative but I would have to come across a good used one at a good price.

BTW, you right the dc/dc converter in this unit s**ks. //content.invisioncic.com/y282845/emoticons/wave.gif.002382ce7d7c19757ab945cc69819de1.gif

 

[-DOZER-]

examples? All the ones ive ever seen have 4v+

x3

 

[-DOZER-]

The 6SX seems to be adequate but Im not sure how to adjust the x-overs even after reading the owners manual. The DQX is perfect but too pricey.

 

[ocdadhd]

Thanks, you hit the nail on the head. This was the kind of advice I was looking for. I agree 100% about the bells and whistles, but I just cant spend any coin on a new HU right now. The audio control EQ's seems to be a better alternative but I would have to come across a good used one at a good price.
BTW, you right the dc/dc converter in this unit s**ks. //content.invisioncic.com/y282845/emoticons/wave.gif.002382ce7d7c19757ab945cc69819de1.gif

Sounds more like you wanted someone to agree with you, as oppose to inform you.

My first deck was an Alpine CDA 9847 with 4Vpreouts. My current deck, a Pioneer DEH-P6600, sounds way better.....& it has 2V preouts.

 

[150dbs 10+ year member]

My .02 is that the only pro's for higher preouts is that you can set the gain lower. The pros of that are of course that the amp will run cooler and less distortion. Moreso the amp will run cooler.

 

[ocdadhd]

My .02 is that the only pro's for higher preouts is that you can set the gain lower. The pros of that are of course that the amp will run cooler and less distortion. Moreso the amp will run cooler.

True, however, none of that really matters if you have a nice amp.

 

[helotaxi 5,000+ posts]

Examples? All the ones Ive ever seen have 4v+

My bad, make that 500mV in the case of the Alpine 7909...

 

[bubbagumper6 5,000+ posts]

My god, so much misinformation in here it's ******* ridiculous. Helotaxi already stated it, the SQ of your system depends on the quality of your equipment NOT the pre-out voltage. If your amplifier is of any quality at all there will be no audible difference between a 2v, 4v, 6v, or even 8v preout, PERIOD. Stop buying cheap equipment then worrying about SQ, that's like buying a Ford Taurus and worrying about what your quarter mile time is.

As a side note...helotaxi where the heck have you been? I haven't seen you around for a long time...

 

[ocdadhd]

My bad, make that 500mV in the case of the Alpine 7909...

Introduced in 1989 with an MSRP tag of $1,200. Named the best head unit of all-time, in a car audio magazine I read earlier this year. However, it had 4v pre-outs. lol

 

[ocdadhd]

My god, so much misinformation in here it's ******* ridiculous. Helotaxi already stated it, the SQ of your system depends on the quality of your equipment NOT the pre-out voltage. If your amplifier is of any quality at all there will be no audible difference between a 2v, 4v, 6v, or even 8v preout, PERIOD. Stop buying cheap equipment then worrying about SQ, that's like buying a Ford Mustang and worrying about what your quarter mile time is.As a side note...helotaxi where the heck have you been? I haven't seen you around for a long time...

fixed //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

 

[whitedragon551 5,000+ posts]

Introduced in 1989 with an MSRP tag of $1,200. Named the best head unit of all-time, in a car audio magazine I read earlier this year. However, it had 4v pre-outs. lol

Its 500mV

Specifications:General:

Output voltage (Preamp) ~ 500mV

Bass Adjustment ~ +/- 18 dB @ 30 Hz

Treble Adjustment ~ +/- 15 dB @ 15 kHz

Dimensions ~W 7" x H 2" x D 6-1/8"

Compact Disc Player:

Samplying Freq ~ 352.8 kHz (8x Oversampling)

# of D/A Converters ~ 2

# of Quantization Bits ~16-Bit Linear System

Freq. Response ~ 5 Hz - 20 kHz

Wow & Flutter ~ below measurable limits

THD ~ 0.002% @ 1 kHz

Dynamic Range ~ 100 dB

SNR ~ 110 dBA

Channel Separation ~ 95 dB @ 1 kHz

AM Tuner:

Sensitivity ~ 10 uV

FM Tuner:

Mono usable sensitivity ~ 16.3 dBf (1.8 uV/75 ohm)

50 dB Quiet Sensitivity ~ 20.7 dBf (3.0 uV / 75 ohm)

alternater channel selectivity ~ 80 dB

SNR ~ 60 dB

Stereo Separation ~ 35 dB

Capture Radio ~ 2.0 dB

AM suppression ~ 45 dB

 

[ocdadhd]

Its 500mV

interesting. The article I read said 4V, I guess Alpine would be a better source.

 

[whitedragon551 5,000+ posts]

interesting. The article I read said 4V, I guess Alpine would be a better source.

A little off topic but here is a screenshot out of the 7909 manual:

 

[-DOZER-]

To provide a clearer picture my amp is a Alpine MRV-F345

• 75 watts RMS x 4 at 4 ohms (85 watts RMS x 4 at 2 ohms)
  
• 300 watts RMS x 1 (channels 3/4) + 75 watts RMS x 1 (channels 1/2) in bridged mode
  
• Amp Link allows single cable connection for signal and control with compatible Alpine receivers
  
• 2-, 3-, or 4-channel output
  
• Tri-way capable (Tri-Way Crossover required)
  
• requires 8-gauge power and ground leads
  
• Bass Engine® features:
  
• Variable 30-400 Hz high-pass/low-pass digital filters, 12 or 24 dB/octave
  
• Rear channels have a subsonic filter at 15 Hz
  
• MOSFET power supply
  
• STAR Topology (minimizes internal noise and prevents ground interference)
  
• Speaker- and preamp-level inputs