Please critique my active system - diyAudio
Go Back   Home > Forums > Source & Line > PC Based

PC Based Computer music servers, crossovers, and equalization

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 29th June 2014, 11:17 AM   #1
diyAudio Member
 
Join Date: Sep 2008
Location: Bristol
Default Please critique my active system

I am trying to establish a reference system for building speakers, and trying to figure out where best to improve my active system.

MacBook - Optical out - DigiFP & MiniDSP 2x8 & Vol FP - Rotel RMB 1048

So currently all 8 channels are actively XO'd, which gives me great scope to do A-B switching, and testing out up to 4 way speakers.

I have a few distinct current approaches:

True full range (using Mark Audio)

F.A.S.T with full range assisted by a woofer

Front horns, up to 3 way.

Currently all speaker cables are Cat6, and phono's are a mix of low end QED and some real cheap freebies.



I figure the source is pretty good, (solid state, battery power, can use AdniNirvana to avoid OSX's meddling). But perhaps USB instead of mini-toslink?

All cables could be improved upon...

MiniDSP, I would love to compare to the Hypex DLCP

Amps, while 8 channels is nice, not entirely needed, curious if improving these (perhaps a single pair of nCores) would yield good results?

If you were me, where would you start?
  Reply With Quote
Old 1st July 2014, 03:44 PM   #2
diyAudio Member
 
Join Date: Nov 2004
Location: Germany
Let me get this straight: You're using network cable as speaker wire? Who came up with this nonsense? What about plain ol' reasonable-gauge twin lead? (0.75 mm to 4 mm, depending on length - whatever does not degrade amplifier damping factor significantly.) The leads in network cable are pretty thin, not much cross-section there. I bet even lamp cord would have a lot less resistance.

Given the galvanic isolation afforded by Toslink, it does not matter whether the computer is mains- or battery-powered.

I hope you have optimized your gain structure for low noise.
  Reply With Quote
Old 1st July 2014, 04:00 PM   #3
sippy is offline sippy  United Kingdom
diyAudio Member
 
Join Date: Jun 2008
Quote:
Originally Posted by sgrossklass View Post
Let me get this straight: You're using network cable as speaker wire? Who came up with this nonsense?
Lots of people do - my cables range from 4 strands out and back of Cat5e (some people use single strands out and back) up to 30amp cooker flex and everything in between.
  Reply With Quote
Old 1st July 2014, 08:19 PM   #4
diyAudio Member
 
Join Date: Sep 2008
Location: Bristol
Lots of people do, they are solid copper and have to be made to a high spec to carry information.

Mine are single cables, with 4 coloured wires for + and 4 whites for -

I haven't messed around with any gain settings, with my ear next to the compression driver, and everything turned up, there is almost no hum or hiss.
  Reply With Quote
Old 1st July 2014, 11:52 PM   #5
DUG is offline DUG  Canada
diyAudio Member
 
Join Date: Jan 2003
Location: mississauga ontario canada
Cat5e cable is also designed to be used for 100 ohm impedance.

So if you use 12 pairs (without interaction between pairs) you will come close to 8 ohm correctly terminated loading.

(not my preference, though)

__________________
Doug We are all learning...we can all help
"You can't stop the signal, Mal. Everything goes somewhere..."
  Reply With Quote
Old 2nd July 2014, 12:18 AM   #6
diyAudio Member
 
abraxalito's Avatar
 
Join Date: Sep 2007
Location: Hangzhou - Marco Polo's 'most beautiful city'. 700yrs is a long time though...
Blog Entries: 98
Send a message via MSN to abraxalito Send a message via Yahoo to abraxalito Send a message via Skype™ to abraxalito
Quote:
Originally Posted by Studio Au View Post
If you were me, where would you start?
Begin with the source (GIGO) - so much better (aka lower noise modulation) DACs than the ones on-board the miniDSP. +1 for the Cat5 cables, I'm a devoted user too.,
__________________
It doesn't have to take the form of a conspiracy, rather a consensus... James H Kunstler
  Reply With Quote
Old 2nd July 2014, 08:17 AM   #7
diyAudio Member
 
Join Date: Sep 2008
Location: Bristol
Source: Yes this has to be where to start, Unless I pick up an old very good CD player/transport, the MacBook offers the convenience of being able to play any file, spits out digital (perhaps using usb& spdif is preferable to the clocked toslink?) is small quite and has a screen.

I have some Hi-Res files, some ripped CD's in iTunes, and Spotify for listening to new music.

The DAC's on the miniDSP board, I believe are quite good, but the whole board is $300, so how good can they really be. Adding DACS afterwards would be great, but at 8 channels gets complicated and expensive quick!
  Reply With Quote
Old 2nd July 2014, 08:46 AM   #8
diyAudio Member
 
abraxalito's Avatar
 
Join Date: Sep 2007
Location: Hangzhou - Marco Polo's 'most beautiful city'. 700yrs is a long time though...
Blog Entries: 98
Send a message via MSN to abraxalito Send a message via Yahoo to abraxalito Send a message via Skype™ to abraxalito
If you have 4 streams of I2S then 4 * TDA1387 will hardly put a dent in your wallet at their current price (from $4 down to $0.10 each depending on where you buy). Admittedly the chip itself isn't a total solution you'd need to add I/V and perhaps filtering.
__________________
It doesn't have to take the form of a conspiracy, rather a consensus... James H Kunstler
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
4 way active system lduarte1973 Multi-Way 14 15th May 2012 03:10 PM
Active 3 way system Bernards Radio Solid State 2 14th June 2011 09:40 AM
My New Active 3-Way System wigginjs Multi-Way 15 26th October 2009 08:06 PM
Zobel for Active system BlairHatcher Chip Amps 9 30th October 2004 08:11 AM
possible active system bonsai171 Solid State 5 13th July 2004 03:41 AM


New To Site? Need Help?

All times are GMT. The time now is 11:59 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2