Audio Systems Find answers to all of your stereo, speaker and other audio technology questions here.
Sponsored by:
Sponsored by:

Double compression

Thread Tools
 
Search this Thread
 
Old Aug 17, 2016 | 02:21 PM
  #1  
Makdaddy's Avatar
Makdaddy
Thread Starter
|
Road Master
Joined: Jul 2009
Posts: 830
Likes: 44
From: Illinois
Default Double compression

I have seen a lot of guys gravitating to the nicer Kenwood and Sony head units.
I have some experience with the Kenwoods and wanted to add a little insight here.

If you are setting a cutoff to your front speakers of say 80 Hz in your deck,
There may not be a need to engauge the filter on your amp if it has one. It should be set to full pass

In other words you dont want to filter the front at 80hz on the head unit, and the kick on the High pass filter on the amp for the front channel.

What you get is double compression.
This could be the cause of muddy audio depending on the system.
Weaker systems will hear the hit more then a high end system.

So just be careful where and when you apply a slope or gain cutoff in the head unit.
Maybe Im only pointing out the obvious
If so I apologize.
 
Reply
Old Aug 17, 2016 | 03:05 PM
  #2  
flcusat's Avatar
flcusat
Tourer
Joined: Aug 2016
Posts: 432
Likes: 10
From: Miami/FL
Default

Thanks for sharing.
 
Reply
Old Aug 17, 2016 | 03:45 PM
  #3  
Rockford Fosgate's Avatar
Rockford Fosgate
Former Sponsor
Joined: May 2014
Posts: 256
Likes: 52
From: Tempe, AZ
Default

Great topic Makdaddy,

Since the internal radio crossover is a 12dB/octave filter at 80Hz, you *can* actually use the amplifier's crossover too, but it MUST be set to the same frequency. If not, you may encounter those weird anomalies you described...

The most common filters are as follows, with the higher order slopes filtering "faster" than the lower ones:

1st order = 6dB/octave
2nd order = 12dB/octave
3rd order = 18dB/octave
4th order = 24dB/octave

The below graph shows how fast the crossover works at different orders. The crossover frequency in this example is 1kHz, but it works the same for 80Hz. With higher order crossovers, you hear less "bleed through" below the crossover frequency.



So if you use the radio's built-in 80Hz High-Pass (12dB) crossover combined with an amplifier's 80Hz High-Pass (12dB) crossover, the net result will be a 24dB/octave crossover at 80Hz. Pretty simple, right?

The practical side, is if your midrange are bottoming out during high output, use a higher order crossover (24dB) or increase the crossover frequency from 80Hz to say 90Hz or even 100Hz.
 
Reply
Old Aug 17, 2016 | 05:05 PM
  #4  
flcusat's Avatar
flcusat
Tourer
Joined: Aug 2016
Posts: 432
Likes: 10
From: Miami/FL
Default

Very interesting. Thanks.
 
Reply
Old Aug 17, 2016 | 06:45 PM
  #5  
Makdaddy's Avatar
Makdaddy
Thread Starter
|
Road Master
Joined: Jul 2009
Posts: 830
Likes: 44
From: Illinois
Default

Originally Posted by Rockford Fosgate
Great topic Makdaddy,

Since the internal radio crossover is a 12dB/octave filter at 80Hz, you *can* actually use the amplifier's crossover too, but it MUST be set to the same frequency. If not, you may encounter those weird anomalies you described...

The most common filters are as follows, with the higher order slopes filtering "faster" than the lower ones:

1st order = 6dB/octave
2nd order = 12dB/octave
3rd order = 18dB/octave
4th order = 24dB/octave

The below graph shows how fast the crossover works at different orders. The crossover frequency in this example is 1kHz, but it works the same for 80Hz. With higher order crossovers, you hear less "bleed through" below the crossover frequency.



So if you use the radio's built-in 80Hz High-Pass (12dB) crossover combined with an amplifier's 80Hz High-Pass (12dB) crossover, the net result will be a 24dB/octave crossover at 80Hz. Pretty simple, right?

The practical side, is if your midrange are bottoming out during high output, use a higher order crossover (24dB) or increase the crossover frequency from 80Hz to say 90Hz or even 100Hz.
Exactly
Thanks for the more technical explanation
I know a lot of guys are new to this
I can see someone having issues, Im just hoping it may help some
 
Reply
Old Aug 28, 2016 | 06:12 PM
  #6  
flcusat's Avatar
flcusat
Tourer
Joined: Aug 2016
Posts: 432
Likes: 10
From: Miami/FL
Default

Is there any particular reason to choose the crossover settings on the head unit over the one at the amp?
Looks like the one of the advantages of the X998 over the Sony Head Units is that it has separate crossovers for the front and rear. In that case a setup with a Sony HU might be better served with a Full setting at the HU and the use the amps crossovers.
 
Reply
Old Aug 28, 2016 | 06:26 PM
  #7  
slyedog's Avatar
slyedog
Elite HDF Member
Joined: Aug 2013
Posts: 3,789
Likes: 276
From: Hawkeye state
Default

Originally Posted by flcusat
Is there any particular reason to choose the crossover settings on the head unit over the one at the amp?
Looks like the one of the advantages of the X998 over the Sony Head Units is that it has separate crossovers for the front and rear. In that case a setup with a Sony HU might be better served with a Full setting at the HU and the use the amps crossovers.
With the head unit you have more slope and know exact frequency vs a pot and a 12 db ( Average slope on most amps). You can have much more precision with fine tuning using the head unit vs the amp.
 
Reply
Old Aug 28, 2016 | 06:37 PM
  #8  
Makdaddy's Avatar
Makdaddy
Thread Starter
|
Road Master
Joined: Jul 2009
Posts: 830
Likes: 44
From: Illinois
Default

Originally Posted by slyedog
With the head unit you have more slope and know exact frequency vs a pot and a 12 db ( Average slope on most amps). You can have much more precision with fine tuning using the head unit vs the amp.

^^^^^^ This
 
Reply
HD Forum Stories

The Best of Harley-Davidson for Lifelong Riders

story-0

8 Best Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-1

10 Worst Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-2

Killer Custom's Jail Break Is The Breakout That Refused to Blend In

 Verdad Gallardo
story-3

Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

 Verdad Gallardo
story-4

Harley-Davidson Reveals Super Cool Cafe Racer Concept

 Verdad Gallardo
story-5

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

 Verdad Gallardo
story-6

10 Motorcycles You Should Never Buy

 Joe Kucinski
story-7

10 Things Harley-Davidson Needs to Fix in 2026

 Verdad Gallardo
story-8

Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

 Verdad Gallardo
story-9

The Best and Worst Harley-Davidson Moves of 2025

 Verdad Gallardo
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
JHC210
Audio Systems
61
Jun 16, 2019 10:58 PM
Sneaky300
Audio Systems
7
May 22, 2018 12:20 PM
Soulkeeper33
Audio Systems
1
Apr 22, 2018 04:46 AM
Cheesehead_13
Audio Systems
1
Dec 17, 2017 06:56 PM
Teufelhunden
Audio Systems
11
Jul 20, 2017 12:53 AM




All times are GMT -5. The time now is 08:01 AM.

story-0
8 Best Harley-Davidson Motorcycles Ever

Slideshow: Not every Harley gets it right, but these are the ones that genuinely earned their reputation.

By Pouria Savadkouei | 2026-04-15 14:23:21


VIEW MORE
story-1
10 Worst Harley-Davidson Motorcycles Ever

Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.

By Pouria Savadkouei | 2026-04-01 20:01:09


VIEW MORE
story-2
Killer Custom's Jail Break Is The Breakout That Refused to Blend In

Slideshow: Killer Custom's "Jail Breaker" build focuses more on stance and visual aggression than mechanical overhaul.

By Verdad Gallardo | 2026-03-18 19:20:32


VIEW MORE
story-3
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.

By Verdad Gallardo | 2026-03-07 16:15:30


VIEW MORE
story-4
Harley-Davidson Reveals Super Cool Cafe Racer Concept

Slideshow: Harley-Davidson's new RMCR concept revives the café racer formula with modern hardware-and it may be exactly the reset the company needs.

By Verdad Gallardo | 2026-03-04 12:23:37


VIEW MORE
story-5
Engraved Rebellion: Inside Bundnerbike's Glam Rock II

Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.

By Verdad Gallardo | 2026-02-24 18:19:44


VIEW MORE
story-6
10 Motorcycles You Should Never Buy

Slideshow: There is no shortage of great motorcycles to buy, but we would avoid these ten.

By Joe Kucinski | 2026-02-19 14:50:51


VIEW MORE
story-7
10 Things Harley-Davidson Needs to Fix in 2026

Slideshow: Harley-Davidson's challenges aren't abstract; they show up in dropping shipments, shrinking dealer traffic, and strategic decisions that aren't yet translating into growth.

By Verdad Gallardo | 2026-01-13 18:33:17


VIEW MORE
story-8
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

Slideshow: Graeme Billington's left-hand-drive Shovelhead is as much about problem-solving as it is about classic Harley form.

By Verdad Gallardo | 2025-12-30 11:27:08


VIEW MORE
story-9
The Best and Worst Harley-Davidson Moves of 2025

Slideshow: A clear-eyed look at what actually worked for Harley this year, and what quietly undermined its progress.

By Verdad Gallardo | 2025-12-29 17:10:48


VIEW MORE