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Have you ever had problems of getting your Replifex to give you ping-pong delay? It's not easy to understand how to do it unless you understand how the delay-circuit of the Replifex works. Get hold of your user's manual, and turn to page 12, the block diagram (if you haven't got the manual you can get it from Rocktron's web site (look under "Support" for their manuals) but it's unfortunately a low quality scan).

The delay-circuit starts with a mixer between Source 1 & 2, where Source 1 always is Voice 1 from the modulation circuits (chorus/flanger) and Source 2 can be switched between Voice 2 from the mod circuits or the direct signal. This lets you control whether you either voice(s) from the mod circuits or just the direct signal. It then goes into the pre-mute switch which is controlled by the Mute Type parameter. This switch is actually the Delay I/O switch. If you set Mute Type to "pre" this is the switch that controls the delay effect on/off, so you can turn off the effect and let the delays trail off.

Next is another mixer, unity gain, which simply sums the input signal and the two regenerated signals and feeds it to the Delay EQ. Then we get to the actual Delay part, where the signal is split into delay 1 & 2 and fed to the post-mute switch. This switch is like the pre-mute switch, and controlled by the Mute Type parameter and the Delay I/O parameter. After the switch each signal is split. One path leads back through each regeneration pot, separate for each delay. The other path goes into separate panning pots for controlling of L/R pan.

I found the delay circuitry to be fairly complicated to understand, but once I had fiddled around with the parameters and listened to how things ended up sounding I figured it out. It might be easier to understand with an example setting, so lets set it up for a standard Pink Floyd "Another Brick In The Wall part 1" delay. It gives the delay I want for that particular song, and with a little tweaking you can use it on "Run Like Hell" too.

First, go to the delay section of the parameters (by turning the function select wheel). Make sure you have "Delay I/O" set to "ON", or you won't get any delay at all. From now on we'll step through the delay parameters, taking it one by one.

I have "Mute type" set to "PRE". Since I don't switch delay in and out during play, it doesn't really matter. If you control Delay I/O using a MIDI controller and want your delays to trail off naturally you'd want to use "PRE".

The "Time1" & "Time2" parameters are set to "OFF" since I don't want to have my delay messed up if I'm so unlucky that I suddenly step on my tap-tempo switch (I have an instant access switch assigned to tap-temp on my All Access). I haven't found a way to get the right delay settings unless I enter the values manually and so I set the tap-tempo parameters to "OFF".

"Delay Lvl" is on my rig set to "0" (zero), set it to whatever you think is the right level. Remember that this setting affects both the delay channels. I therefore use it to set the overall delay level.

"D-Mix S1/S2" is on my rig set so that I only get the S2 signal. I run most of my effects in parallell, and therefore I want to make S2 be the direct signal. Likewise the "Source 2" parameter is set to "Direct".

"Dly Hf Damp" is something I adjust depending on the sound that I want. If I want a mid/bass kind of delay I set it to a fairly high value. Usually I want a quite crisp delay, so I set it to zero. This is also a thing which is rig-dependent, so you can do whatever you like with it.

"Delay Out 1" is on this particular preset set to "0" (zero), since I want a fairly loud delay signal. This is something you should remember to adjust depending on whether you run stereo or mono delays. That is because if you run a stereo delay your signal will be louder since you have two delay signals instead of only one. Since I want a loud delay I set it to zero.

"Dly Pan1" is set so that the signal only comes out of the left channel (remember that I run a stereo rig and want a stereo ping-pong effect). If you have a mono rig you won't hear any difference between left or right but that does not mean that you can set it to the middle setting and get ping-pong delay. You will have to set it to either 100% left or right (I choose left) if you want the desired effect.

"Dly Time1" is for this specific preset set to "300 ms". I will further down, when I talk about the setting for the second delay, explain how to compute the settings. Therefore, if you want to change the setting, make sure to read that part before you try things out, or you might not get the effect you want. "Fine 1" is set to "0" (zero). This is just because I want a delay of 300ms, nothing else.

"Dly Rgn 1" is set to "-inf" (sorry, no infinity-symbol here). The key to understand this setting is to remember that the two delay signals get mixed together before they enter the eq-delay chain again. Therefore I want to have only one delay in the left channel, making sure I don't make an unevenly repeated signal. If you set it to something else, you'll soon notice the difference.

"Dly Out 2" is set to the same value as "Dly out 1" which was "0" (zero). That is to make sure that both delays have the same level. If you change one, you might want to change the other too. And, as I noted, the easiest way to adjust both levels evenly is with the "Delay Lvl"-setting.

"Dly Pan 2" is set so that the signal only comes out of the right channel. As I've already pointed out, you'll have to keep the signals to each other's channel, even though you run mono. If you don't, your effect won't be like it should.

"Dly Time2" is for this specific preset set to "450 ms". This gives you a triplet-feel delay. What you do is that you take the second setting, and make sure it fits with one beat of the song. Then you divide that setting into 3. 450/3 is 150, thus giving us 150ms between each delay. Since we are making a delay for "Another Brick In The Wall" we want an uneven triplet delay. That's why we set the first value to 300 ms (two triplet beats). Another way to look at it is to take the first value, divide it by 2, and then add the number you get to the other value. You can then easily compute settings for each 10ms step in the first delay. I'll write more about it when we're finished with the parameters.

"Fine 2" is set to "0" (zero), since I want exactly 450ms (300/2 + 300 as before noted). If you start with 310ms you would want the next to be 465, thus setting the time to 460 and the fine-value to 5.

"Dly Rgn 2" is set to "-9" (I think, I don't have my rig here now so I can't check). This regeneration value is the one adjusting how many repeats you want. So if you want many repeats, set this to a high value (like -3 or -6), fewer delays gives lower values (-15 & -18 for example). Notice that all regeneration happens in the second delay unit.

"D > Spillover" is a parameter I usually set to off, since I don't want my delay settings to be different when I change presets. I've had problems, since I sometimes set it to "on", change presets, and then store the preset. This will give you the delay settings of the first preset stored in the second. If you have for example a difficult setup like the one we have here, you don't want it ruined. That's why I now mostly set it to off.

Ok, that's all there is to it. If we now take our example, and feed a signal to it, here's what will happen: First, the original signal is heard (time = 0ms). Then the 300ms delay comes (time = 300ms or the 3rd triplet beat), but no regeneration occurs. Next is the 450ms delay (time = 450 ms or the 4th triplet beat). The signal at 450ms is fed back through the regeneration circuit and arrives at input, slightly lower in level. Nothing happens then until 750ms, which is that 450ms signal delayed by 300ms, and so the cycle continues.

It's not very complicated, and if you give it some math you can come up with pretty interesting delays. I've tried taking the first signal 300ms, and divide it by 3 instead of 2. You then get 300ms and 400ms, and a completely different effect. I've also tried dividing it by 4, taking 400ms and 500ms (400 + 400/4), again something different is the result. You can try things out, using even or unevenly distributed delays. For example, if you set the first delay to 150ms and the second to 300ms you get an even 150ms delay. Uneven delays are the result of setting the first to a time different from the 2nd beat of the song. You still might want to sync with the song, though.