Latest Recommended Hardware Configurations (2/17/2019)
Starting at highest performance
- Wireworld Platinum USB cable -> SOtM tX-USBultra regenerator -> Wireworld Platinum USB cable -> Overdrive SX or Off-Ramp 6 using new XMOS USB interface (Best playback software is Amarra)
- AQVOX AQ-Switch SE -> 0.5m Wireworld Platinum Ethernet cable -> EMO EN-70e Isolator -> SOtM dCBL-CAT7 Ethernet cable -> Overdrive SX with Ethernet interface or Interchange Ethernet Renderer (Best Software is Linn Kinsky/Minimserver/BubbleUPnP as a proxy server)
- (Sonos, Squeezebox, Servers, Apple TV etc..) -> Empirical Audio Standard BNC cable -> Synchro-Mesh powered by Dynamo LPS -> Empirical Audio Reference 4-foot BNC-BNC S/PDIF coax cable -> Overdrive SX or the DAC of your choice, preferably without internal reclocking to achieve the full benefit.
Best Computer Source
The best USB source we have found is the late 2009 Mac Mini with SSD and at least 4GB DRAM. Use USB port next to the center one. Better than newer Minis, but the latest OS that you can load is El Capitan. The SSD can be purchased from Other World Computing. 120GB is recommended. This is a 30-minute task to replace the hard disk yourself:
http://eshop.macsales.com/shop/SSD/OWC/Mercury_Electra_6G/
You can get it with a USB-ATA adapter so the drive can be plugged into a USB port for formatting prior to swapping the hard drive and installing in the computer (recommended). They do not come formatted:
http://eshop.macsales.com/item/Other%20World%20Computing/Y3SSD6E120/
If you are using Ethernet, practically any computer and many portable devices can be used. The important part is the router or switch, not the computer.
Power Supplies
The Mac Mini and Synchro-Mesh can be further improved be replacing the wall-wart AC adapter with a Dynamo fast-reacting linear supply. All LPS are not the same. They need to be fast-reacting for digital and most are not. The SOtM regenerator for USB is better if powered from their upgrade LPS.
DAC enhancements
If your preamp or amp does not have balanced inputs, the Empirical Audio Final Drives can provide the transition from balanced to single-ended.
System Equalization
I know, EQ was a dirty word to audiophiles in the past, but trust me, no more. The parametric EQ that comes standard with Amarra is truly transparent and can take your speakers to the next level. If you have speakers that cost $15K and want them to sound like $100K, this will get you there.
The EQ in Amarra is easy to use. For each correction, you have these parameters to adjust: Amplitude, Frequency and Q. Q is the spread of the effect, so a high Q like 25 will be a very narrow correction. Q of 2 will be wide, covering a wide range of frequencies on both sides of the Frequency selected.
EQ is not something that you want to be adjusting by ear, because this is very tricky and error-prone. Instead, one needs a Spectrum Analyzer to show you the response from 20Hz to 20kHz in your specific room. You play a pink noise file in repeat mode from the computer to give you the flat signal and then a microphone and analyzer will show you where in the frequency range the suckouts and bumps are. You can then adjust the Frequency, Amplitude and Q in real-time to eliminate these suckouts and bumps. Typical EQ will have one or two corrections for the crossover in the speaker (they are never perfect) and one or two for room resonances. Amarra standard EQ has 3 corrections, but you can call-up the advanced version in the Amarra preferences to get 4 corrections if you need more than 3.