Spider Jam Troubleshooting
Hiss, hum and all that jazz.
Hiss, hum and all that jazz.
All amplification devices produce a degree of hiss (white noise) but some more than others. Modern low-noise transistors and integrated circuits manage to keep hiss to imperceptible levels under normal operating conditions but if you have to turn the volume up because your mic or guitar has low output or is mismatched in some way, the 'signal to noise ratio' will be poorer.
In a Spider Jam (or JM4 Looper) the most likely cause of hiss is from the MIC pre-amp. This circuitry has to amplify the relatively weak signals coming from a microphone to an acceptable level - and microphones vary enormously in the amount of signal they put out.
The microphone LEVEL control on the inputs panel is there to compensate for variations in microphone signal strength. You should turn this up until the clipping light just starts to glow on strong vocals. This is similar to the DRIVE control for guitar inputs except that where distortion on guitar signals is acceptable, or even desirable, distortion on a microphone is not.
The equivalent of the CHANNEL VOLUME for the MIC input is hidden two levels down on the INPUTS/LEVEL button menus. It has a level meter and a reading in dB (decibels) which can be adjusted with the large Select knob on top.
If the dB setting is high (over 0dB) and the mic LEVEL is turned up high too, you will certainly hear a hiss as the master volume is turned up. This happens whether there is a mic plugged-in or not.
Reducing the MIC input to -10dB or less will reduce the hiss to acceptable levels.
Any other input, (AUX, CD) that is not being used should also be kept as low as possible to keep hiss to a minimum.
Hum is caused by AC from the mains getting through to the signal path.
Guitar and microphone cables are 'screened' to eliminate AC hum. The 'hot' central conductor is surrounded by a sheath of copper braid which is connected to ground and acts as a shield against induced AC signals.
It is not just cables that are screened, the entire signal path inside an amplifier is screened too. The metal chassis acts as the first line of defence but there are components inside an amp that carry alternating currents - the mains transformer/power supply, fuses, the power switch and some ON indicator lights are all sources of hum.
There is potential for hum inside the chassis and additional screening has to be provided through layout design considerations – high gain parts of the pre-amp should be as far as physically possible remote from hum-inducing components and grounded metal barriers should also be put between such components.
If you can hear humming from your amp, there can be a number of causes:-
If the hum is only audible when your guitar is plugged-in, the problem is with the guitar or guitar cable. Single coil pickups are especially susceptible to hum induced by lighting, computers or other nearby electrical equipment but poor quality or faulty cables can also cause problems.
If you can hear hum and there is nothing else plugged-in, it indicates a bad internal ground connection. This can be caused by a faulty component but is more likely a loose connection. See the FIXES section.
Hum can also be caused by connecting to other equipment such as PA systems or computers. This happens when a condition called a 'ground-loop' is set up.
A ground-loop happens when two (or more) pieces of electronic equipment are connected together and they are both connected to ground AND they are also interconnected by screened cables. This means that they are being grounded twice but because all electrical connectors have some degree of resistance, the two grounding sources are at slightly different voltages.
One way to fix this is to remove the ground from one of the devices but this is not always convenient (or safe). Another way that works sometimes is to disconnect the ground from ONE end of the interconnecting cable(s). This means that the cable is still screened but there is no physical ground interconnection.
The most reliable and safest way to eliminate ground-loops is by using a device called a DI (direct-injection) box with ground lift. This uses a transformer (passive) or active circuit that passes the signal through without a physical ground interconnection. DI boxes are generally inexpensive and if you suffer from hum, the best possible solution.
Crackles and pops are usually caused by bad electrical connections somewhere in the signal path. This can be due to dry soldered joints, dirt and dust in plugs and potentiometers, poorly seated connectors and cabling.
One major 'crackle' that took me by surprise was when I first turned on my Spider Jam. When the power is switched-on, there is a short delay, then a crackle and pop before the amplifier springs to life. This is quite normal and nothing to be concerned about. The Spider Jam is essentially a computer connected to an amplifier and all that is happening is that the computer is still in the process of booting and settling in when the amplifier has just warmed up.
This can be worrying but don't panic.
First thing is to check the fuses. There is a hidden fuse just below where the mains plug goes into the back of the amplifier (outlined in red). It is inside a little drawer that has to be prized out with a screwdriver or such. There may also be a fuse in the plug at the other end of the mains cable. With a glass fuse, you can usually see that it has blown as the fuse wire inside is melted and has blackened the inside of the glass envelope in the process. Sometimes, it is not all that obvious and you have to test for continuity with an meter or continuity tester. Be sure to replace any blown fuse with one of the same value. When fuses blow, there is always a root cause. The fuse is there for protection and putting in a fuse of higher value just passes the stress on to somewhere else that is more expensive to fix.
If all the LED lights have come on but there is no sound from some or all of the sound sources, try turning up the master volume. If you can hear nothing at all, no hiss or hum, it means that no power is going to the speakers. First check that the speaker wires have not come adrift. If they are obviously intact, it would suggest a problem with the power amplifier and the amp needs to go to a service centre.
If you can hear a hum or hiss when the master volume is turned up, it means that no signal is getting to the power amp. This could be your settings – some of the level controls are not all that obvious. First check that the internal drums/songs are working. Turn up the master volume to 10 o'clock and go into the INPUT/LEVELS menu and adjust the on-screen levels (one press) and sensitivities (two presses).
Now here is a real gotcha! There are two output routing options under SETTINGS/TONE (two presses) OUTPUT ROUTING. NORMAL sends all the songs/drums/guitar/mic signals to the output (speakers). If set to PERFORMANCE, only the GUITAR comes out of the speaker. All the other signals are sent to the RCA sockets on the back to be processed by an external amplifier or PA system. If your guitar is working but nothing else, this is the place to check!
If this doesn't bring your sounds back, you can try a factory reset. Turn off the amplifier, holding down the SETTINGS/TONE button and switch on again keeping the button held down for 5-8 seconds. Note that this will wipe any custom tones or settings you have made and you should also make sure that any songs or loops are backed up to SD card.
If you are using a LINE6 FBV Express pedal, and your volume goes, you might need to calibrate it. See below.
Rodent infestation! Try ACME Brand mouse traps.
Where you can save recording you have made as .JAM files on the Spider Jam, if you want to take those recording onto your computer to play, your need to use SAVE REC MIX AS WAV TO CARD under the SAVE menu. Some people complain that they can't do this. Hardware issues aside, the main suspect here is the filename.
The FAT 16 file system uses 'eight dot three' filenames so MYSONG01.WAV is a valid filename. It has eight characters (or less) to the left of the dot and the WAV extension after. You don't need to add the .WAV extension yourself. It won't show on the Spider Jam display but it will show on your computer. Don't use any characters other than A-Z, a-z, 0-9 and the underscore '_' or you might have problems.
Filenames can be editied using the LEFT and RIGHT arrows to move the cursor and turning the big silver SELECT wheel to choose the characters. Although there are more characters available than the 'A-Z, a-z, 0-9 _' set, just play safe and stick with those.
These are covered on another page.
The LINE6 FBV Express is designed to work with several LINE6 amps and needs to be properly calibrated for the Spider Jam before using it or you may experience unexpected results. Here is the procedure that worked for me...
Here is a link on another forum about calibrating the larger LINE6 FBV SHORTBOARD.