Know the two boxes
Most hook-up mistakes come from not knowing what each jack expects. Learn these facts first and the rest is routine.
Shure SM58
- Type
- Dynamic (moving coil). It makes its own signal and needs no battery and no phantom power.
- Pattern
- Cardioid. It hears what is in front of the grille and rejects what is behind the handle.
- Output
- 3-pin XLR, male, balanced, low impedance (150 Ω).
- Range
- 50 Hz to 15 kHz, shaped for voice.
- Switch
- The standard SM58 has none. The SM58S variant has an on/off switch on the handle.
Bose T4S
- Inputs 1–4
- XLR combo jacks. XLR for microphones, 1/4-inch for high-impedance instruments such as guitars.
- Aux in 5/6
- 1/4-inch, line level only. Not for a microphone.
- Phantom
- One switch sends +48 V to all four inputs. A red LED shows it is on.
- Main out
- Two ToneMatch ports (digital audio plus power) and a pair of 1/4-inch analog outputs. No XLR outputs; those are on the T8S.
- Power
- From a Bose L1 through the included ToneMatch cable. A ToneMatch power supply is sold separately.
Find your way around the T4S
Tap any control or jack to see what it does. The numbers match the callouts in the Bose owner’s guide. These are simplified drawings, so compare them with the real mixer in front of you.
The signal path on channel 1
- SM58XLR male
- Mic cablebalanced XLR
- Input 1combo jack
- Trim 1input sensitivity
- ToneMatchpreset, zEQ, effects
- Volume 1channel level
- Masteroverall level
- SpeakerL1 or powered PA
Every later chapter is one stop on this line. When there is no sound, walk the line from left to right.
Hook it up
The order matters because it keeps pops and thumps out of the speakers. This sequence follows the Bose owner’s guide.
- Mixer off, speaker off, Master turned to minimum.
- Connect the T4S to the speaker. For a Bose L1 with a ToneMatch port, run the ToneMatch cable from Power port / Digital Main Output R to the L1. For any other powered speaker, run a 1/4-inch TRS cable from Analog Output and power the mixer with a ToneMatch power supply.
- Turn on the mixer first, then the speaker.
- Before the mic goes in, check that the phantom power LED is dark and that Trim 1 and Volume 1 are at minimum.
- Push the female end of the XLR cable onto the SM58 until it clicks, then plug the male end into Input 1.
- Set the level: Trim, then Master, then channel volume. Chapter 3 covers this.
Phantom power stays off. The SM58 does not need it. The switch feeds all four inputs at once, so if another channel has a condenser mic that needs +48 V, the SM58 on a balanced XLR cable is not harmed by it.
The ToneMatch port is not a network port. It accepts an RJ-45 plug, and Bose warns never to connect it to a computer or phone network.
Drill: put the steps in order
Use the arrows to move each step, then check. A row turns green when it sits in the right position.
Set the gain
Three controls set how loud the mic is, and they are adjusted in a fixed order. Trim sets how hard the mic drives the input. Master and channel volume set how much of that reaches the speaker.
- Master, Trim 1 and Volume 1 all at minimum.
- Sing into the mic as loudly as you will during the performance.
- Turn Trim 1 clockwise slowly until the signal LED above it glows green.
- If the LED flashes red or stays red, the input is clipping. Turn Trim counterclockwise until it is green again.
- Set Master to 12 o’clock.
- Turn Volume 1 clockwise slowly until the voice is as loud as you want.
Reading the signal LED
For a closer look, turn the rotary selector to Prefs and open Input Level. It shows a meter with peak indicators for every input.
Bench: fix this channel
Someone left channel 1 in a bad state. Use the controls until all five checks pass. This is a simplified model for practice, and the positions on a real T4S will differ with your voice and distance from the mic.
Pick the tone
A ToneMatch preset is an equalisation curve written for a specific microphone or instrument. Each channel gets its own.
- Press CH Edit 1. The display shows the selected channel in its upper-left corner.
- Turn the rotary selector to ToneMatch.
- Rotate the Category control to Vocal Mics and press Select.
- Rotate the Preset control to your microphone and press Select. Pressing Cancel leaves the list with no change.
Which preset for the SM58? Look for a Shure SM58 entry under Vocal Mics. Bose’s earlier T1 preset list includes one, but the list on your mixer depends on the preset bank that is loaded, and Bose’s T4S documents do not list every entry. If it is not there, Handheld Mics is the general choice.
After the preset
- zEQ gives low, mid and high controls that are shifted into the range of the mic you chose. Press a control to bypass that band.
- Para EQ gives three bands you can place anywhere from 50 Hz to 16 kHz, each with ±15 dB.
- Comp/Gate holds the compressors, limiter, de-esser and noise gate. One per channel.
- Mod, Delay, Reverb are the effects. FX Mute silences these three only.
Things that are not saved
A scene stores the mixer’s settings so you can recall them at the next gig. It does not store Trim, channel volume, Master, headphone level or the phantom switch. Set those by hand every time.
If you want no ToneMatch curve at all, choose Flat in the Utility category.
When it goes wrong
These are the checks from the Bose troubleshooting table that apply to a single vocal mic, in the order of the signal path.
No sound
- Is the signal LED green when you sing? If it is dark, raise Trim, then try another XLR cable.
- Is the Mute button glowing white? Then the channel is muted and the display reads CH MUTE.
- Is Volume 1 up?
- Is Master up?
- Check Prefs for a signal on both the Input Level and Output Level meters.
- On an SM58S, check the switch on the handle.
- Still nothing: turn the mixer off, wait 30 seconds, turn it on again.
Bad sound
- Distorted, LED red: lower Trim until the LED is green.
- Feedback squeal: point the mic away from the speaker, move further from it, lower the high band of zEQ, or notch the ringing frequency with Para EQ.
- Thin or boomy: check that the ToneMatch preset fits the mic and that no stray zEQ or Para EQ is applied.
- No reverb or delay: check that FX Mute is off and that you pressed the right CH Edit button.
- Master does nothing: in Prefs, Master Out should read Post Master Volume.
Using the cardioid pattern. The SM58 rejects sound arriving at the back of the handle. Stand so the speaker or monitor is behind the mic, and hold it by the handle. Covering the grille with your hand changes the pickup pattern and makes feedback more likely.
Test yourself
Twelve questions drawn at random from all five chapters. No feedback until the end. Each run is a different mix.