This article outlines what you can expect from SNR and Attenuation figures from ADSL modems. The tables below should be used to assist you in troubleshooting ADSL quality issues – even service drop-outs.
Attenuation is the loss of signal in a return trip between your ADSL modem and the exchange.
| Attenuation | Expectations |
| 10 | Extremely Good |
| 20 | Very Good |
| 30 | Good |
| 40 | Bad |
| 50 | Very Bad |
| 60 | Extremely Bad |
The Signal to Noise ratio is a measurement of how much noise there is on the ADSL line.
| SNR | Result |
| 6 | Very bad |
| 7 | Bad |
| 10 | OK |
| 20 | Good |
| 30 | Very Good |
