DCAudioDIY.com

DC Area Audio DIYer's Community
It is currently November 5th, 2024, 3:18 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 18 posts ]  Go to page 1, 2  Next
Author Message
PostPosted: August 10th, 2024, 11:58 am 
Offline
User avatar

Joined: January 13th, 2016, 9:14 pm
Posts: 876
Converting a pair of commercial 2-way speakers from the original passive crossover to a dspNexus 2x8 Audio Weaver DSP crossover.

Building an RPi5 driven ABC switch to compare the original passive crossover, a passive crossover with better quality components and the DSP crossover. The user can run a Thonny Python 3 program to switch between all three crossovers after level matching at 1KHz. The Python program is running the GPIO logic now to drive relays for the switching.

Plan to take the setup to CAF2024 in room 702 to demo the system so listeners can hear the differences. But sorry, the subs will not fit in the demo room.


Attachments:
M1+Monoliths.jpg
M1+Monoliths.jpg [ 315 KiB | Viewed 60071 times ]
Top
 Profile  
 
PostPosted: August 21st, 2024, 6:02 pm 
Offline
User avatar

Joined: January 13th, 2016, 9:14 pm
Posts: 876
Building the ABC Switch relay wiring and testing the drive circuit. Using 8-DPDT replays with silver contacts for the speaker level switching between the crossovers.

Decided on a RPi5 using Thonny for Python 3 coding for the logic drive to the GPIO ports. A ribbon cable to the driver board.

Simple relay switching with power MOSFET VN10KM drivers. Each relay coil is 12VDC@0.203A, so the small VN10KM devices will work without a heatsink.

The SMPS is working and will power the RPi5 and all the relay coils.


Attachments:
ABC Relay Set#2.jpg
ABC Relay Set#2.jpg [ 413.63 KiB | Viewed 43949 times ]
ABC Relay Set#1.jpg
ABC Relay Set#1.jpg [ 406.5 KiB | Viewed 43949 times ]
Top
 Profile  
 
PostPosted: September 13th, 2024, 4:09 pm 
Offline
User avatar

Joined: January 13th, 2016, 9:14 pm
Posts: 876
The first ABC Switch relay box #1 prototype is done. The Neutrik connectors are relay switching signals on the front with the outputs to the speaker drivers.

Rear connectors are the ABC inputs from the different crossovers.

Now to build relay box #2.


Attachments:
RelayBox#1-Front.jpg
RelayBox#1-Front.jpg [ 221.38 KiB | Viewed 42808 times ]
RelayBox#1-Rear.jpg
RelayBox#1-Rear.jpg [ 245.18 KiB | Viewed 42808 times ]
Top
 Profile  
 
PostPosted: October 2nd, 2024, 5:01 am 
Offline
User avatar

Joined: January 13th, 2016, 9:14 pm
Posts: 876
Built the relay controller boards and wired them to the relay connectors and SMPS.

Next is wiring the RPi5 ribbon cable to the controller boards and start testing the ABC Switch.


Attachments:
LogicBox-RelayDrivers.jpg
LogicBox-RelayDrivers.jpg [ 380.08 KiB | Viewed 41120 times ]
Top
 Profile  
 
PostPosted: October 4th, 2024, 7:00 pm 
Offline
User avatar

Joined: January 13th, 2016, 9:14 pm
Posts: 876
The ABC Switch RPi5 and Relay control boards are now connected.

Time for some relay testing for channel #1 then swap to channel #2. Then onto both.


Attachments:
RelayBoxTestingChannel#1.jpg
RelayBoxTestingChannel#1.jpg [ 256.17 KiB | Viewed 40611 times ]
Top
 Profile  
 
PostPosted: October 11th, 2024, 5:55 pm 
Offline
User avatar

Joined: January 13th, 2016, 9:14 pm
Posts: 876
The M1 speakers ABC Switch System is ready for testing.

This is the original passive crossover, upgraded component passive crossover and inputs for the dspNexus 2/8 DSP crossover system.

Now for system connection and listening trials. Need to level match the 3 crossovers. Cable lengths for each channel are 8ft of Belden 1309A 14awg speaker cable without the PVC jacket.

Then, let the games begin! :o


Attachments:
ABCSwitchRear.jpg
ABCSwitchRear.jpg [ 238.48 KiB | Viewed 7153 times ]
ABCSwitchFront.jpg
ABCSwitchFront.jpg [ 269.88 KiB | Viewed 7153 times ]
Top
 Profile  
 
PostPosted: October 12th, 2024, 7:10 pm 
Offline
User avatar

Joined: January 13th, 2016, 9:14 pm
Posts: 876
For the upgraded M1 speaker crossover, the original value of two inductors used is not a stock value. Had a matched pair of aircore inductors made for the new passive crossover for the ABC Switch box system.

I will install these and ready for system installation and ABC crossover trials.


Attachments:
M1WooferInductors.jpg
M1WooferInductors.jpg [ 258.3 KiB | Viewed 7101 times ]
Top
 Profile  
 
PostPosted: October 14th, 2024, 4:23 pm 
Offline

Joined: July 17th, 2016, 6:24 am
Posts: 1127
What is the goal of this exercise?

Comparing passive crossovers with active DSP crossovers is not a fair game, as the active DSP crossover optimizes the signal for the listening environment.

Unless, you are trying to show the benefits of active DSP crossover. No?


Top
 Profile  
 
PostPosted: October 14th, 2024, 5:51 pm 
Offline
User avatar

Joined: January 13th, 2016, 9:14 pm
Posts: 876
People have asked how does DSP crossovers compare to original and upgraded passive component crossovers.

I used popular upgrade passive parts so they can hear the differences.

Many people have not heard the differences between what passive and modern DSP crossovers would sound like.

The ABC Switch lets you hear all three with the same music material.

These will be level matched ABC comparisons.


Top
 Profile  
 
PostPosted: October 14th, 2024, 8:13 pm 
Offline

Joined: July 17th, 2016, 6:24 am
Posts: 1127
Sounds good.
Will you be demonstrating it in CAF?


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 18 posts ]  Go to page 1, 2  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 35 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group