Amps, leads, signal chains, where is it wrong

[Woodinblack]

Did two gigs at the weekend, wasn't happy with the sound at either of them. I think the first one was because my cabs were in front of me, rather than behind, and I accidently knocked my bass middle control flat out!

 

However, I am not totally convinced all is well with the ABM600.

 

So it is bass -> backbeat ->wireless -> Effects and Helix HX -> Ashdown -> 2x TC112 speakers. Also a DI from Ashdown to X18 mostly for monitoring, but also a little into the subs as I have just got one.

 

Last night, we did a sound check and set up and all seemed fine. in the second half I couldn't really hear the bass and going out the front, although it was there it seemed lifeless and quiet. The VU meter on the ashdown was hardly moving, but turning up the gain made little difference. However, the meter in the X-Air app for the mixer which was connected to the DI out was moving fine up to just before the red on heavy notes.

Sticking my head into the speakers I wasn't entirely sure something was coming out, couldn't see the speakers move. The Sub was next to the speakers, and bass coming out of that.

Turning the main volume up made little difference too. I quickly (this was mid set) swapped the direction of the speakon leads as I had trouble before with leads, no difference, swapped the way round (they went from amp to speaker to speaker).

Checked helix (I have a direct in from another pedal and that was really loud). 

Flipped the bass between passive and active, no real difference. 

Unfortunately hard to tell what was going on because although I am good at trouble shooting I was panicking a bit.

Something happened, not sure what but I put the distortion on on the helix and almost knocked the first row of tables over! Turned it down and all was good. 

 

So, has anyone had trouble with speakons before, or their ashdown.

 

I realise a few of things here. One, the ashdown has 2 speakons so it would make sense to use both to go individualy to speakers. 2, if the effect into the helix was loud, maybe the problem was before the amp, but that makes no sense with turning the amp up and nothing happening. 3, absolutely noone can really say what was happening as I didn't use much logic as I was flailing!

 

I think I will get a speakon - speakon with a bargraph led meter so I can see how much power is actually going into the speakers as it is just too hard to tell any other way!

[BassmanPaul]

I've never had any trouble with SpeakOns then again I only will use genuine Neutrik brand connectors. Knock off connectors made in China and other Far East countries have been shown to be unreliable.

 

As for troubleshooting it's best to keep your brain active and not panic - difficult though that may be.

[Sparky Mark]

Check that both of the speaker cables are wired the same. If one of them swaps the polarity then that cab will be out of phase with the other and cancel most of the bass response. I've experienced this and it sounds exactly as you have described. 

[Downunderwonder]

''All seemed fine" = no speakon polarity issue.

 

Surge in volume tells you no problem with speakers at least.

 

Mucking around with preamp kicking off the surge says probable dud cable there anywhere between bass and amp. It's either that or you futzed your Helix settings somewhere along the line.

[BassAdder60]

In this situation I would of gone guitar lead straight into ABM600 to check amp lead and bass we’re working as should 

Matter of quick elimination 

[Woodinblack]

8 hours ago, Sparky Mark said:

Check that both of the speaker cables are wired the same. 

 

they arent all the same as some of them only work one way round. Speak on cables are a pain to test!

 

6 hours ago, Downunderwonder said:

. It's either that or you futzed your Helix settings somewhere along the line.

 

I have suspicions about the helix as it keeps accidentally engaging footswitches.

 

3 hours ago, BassAdder27 said:

In this situation I would of gone guitar lead straight into ABM600 to check amp lead and bass we’re working as should 

Matter of quick elimination 

the irony is that at every gig I put a guitar cable on top of the amp in case something happens with the wireless. Was just panicking so much I didn't think of it!

[Sparky Mark]

The Speakon output sockets on the ABM600 will accept 1/4" jack connector speaker cables. It could be worth just checking the amp to speaker connections using one of those.

[Bunion]

 

On 29/08/2021 at 12:40, Woodinblack said:

in the second half I couldn't really hear the bass and going out the front, although it was there it seemed lifeless and quiet. The VU meter on the ashdown was hardly moving, but turning up the gain made little difference

Try plugging a preamp into the effects return and bypass the ash down preamp, if that works fine, could your tube have a problem, become unseated or getting tired? 

[agedhorse]

6 hours ago, Woodinblack said:

 

they arent all the same as some of them only work one way round. Speak on cables are a pain to test!

Standard SpeakOn (non-bridging) are in fact all wired the same... 1+ to 1+ and 1- to 1-  You need to be using a standard SpeakOn cable.  They are not a pain  to test if you have the proper equipment.

6 hours ago, Woodinblack said:

the irony is that at every gig I put a guitar cable on top of the amp in case something happens with the wireless. Was just panicking so much I didn't think of it!

Bypassing all the extraneous "stuff" is one of the most fundamental parts of structured troubleshooting. Panic is not part of the process. Before screwing with anything else, just plug straight into the amp and verify that the basic system is working properly. 

Edited August 30, 2021 by agedhorse

[Woodinblack]

36 minutes ago, agedhorse said:

Standard SpeakOn (non-bridging) are in fact all wired the same... 1+ to 1+ and 1- to 1-  You need to be using a standard SpeakOn cable.  They are not a pain  to test if you have the proper equipment.

 

They are a pain to test as I don't have the proper equipment! Or in this case, just a speakon socket, I thought I had a spare, can't find it.

But clearly there is some difference between my speakon connectors as a couple of them do different things. In future though, I will wire socket to socket, rather than chain them through the speakers, as there would be fewer single points of failure.

 

However, I dont' think this is the issue (although I want to test it) as it was fine at sound check. 

 

Anyway, don't have any gigs for a few weeks so i will take it out and test everything. All the leads that weren't speakons I tested the week before last, and threw everything that wasn't perfect in a pile to be reworked.

 

 

[Phil Starr]

8 hours ago, Woodinblack said:

 

they arent all the same as some of them only work one way round. Speak on cables are a pain to test!

 

 

I have suspicions about the helix as it keeps accidentally engaging footswitches.

 

the irony is that at every gig I put a guitar cable on top of the amp in case something happens with the wireless. Was just panicking so much I didn't think of it!

My heart goes out to you, it's horrible to have an equipment failure at a gig.

 

It's easy to say now but next time use the lead straight from bass to amp and cut out as much as you can, if bass amp and speakers are working you can get to the end of the gig. If they cant then you can then think about going straight to the PA.

 

No-one can be definitive because it sounds like you tried pretty much everything but panic stops you remembering exactly what. To me however if you continued through the PA sub then you had a signal as far as the Ashdowns DI out, and it may be the speakon lead. They generally have screw connectors which means they are easy to fix (no soldering) but fail fairly easily. The grub screw comes loose and you get an intermittent connection until the lead comes right out. 

 

I'm a bit worried about your Helix too, if it is playing up you need to address that too. It may be you have a couple or more faults to sort before the next gig. 

 

There's loads of stuff on YouTube to tell you how to wire a Speakon How to make-wire SpeakON cables for PA speakers #DIY37 - YouTube

 

Looks like you are just down the road from me, pm me if you get stuck

 

Edited August 30, 2021 by Phil Starr

[Chienmortbb]

Firstly let me say I love speakons. I have connected hundreds and as has been said check the screw connections. you need to use a good screwdriver to get a tight grip on the cable. I seem to remember that it is a 1 point posidrive (not philips)..Don't even think about using 4mm2 cable as is too bag for the plastic speakons and if a far heavier gauge than you need. 2.5 mm or even 1.5mm cab is fine.

 

Tighten the screws as hard as you canand then pull the cable as hard as you can to check that you have a good grip. It is never a good idea to daisy chain cabinets, use two separate cables as most good amps have two speakons.

 

As for speakon wiring, 1+ to 1+ and 1- to 1-1 on both 2 pin and 4 pin connectors. The 2+ and 2- are generally used for subs in a bi-amplified system. There are other proprietry wirings that rarely come up.

 

Going back to the system as a whole, in the situation you were in you should have just bypassed the Helix and gone straight into the amp.

[Woodinblack]

Agreed. The only real reason for suspecting the speakons was because the signal on the x18 that came from the ashdown di was showing as fine.

The only new part of this puzzle is the ABM600. The leads, speakers etc all have done the best part of 100 gigs with me without issues, even the helix has done a good 40 or so. The abm600 I got in lockdown as a refurb for half price in Pmt. I am not sure why it was refurb as it was close to immaculate, maybe there was an issue. 

Although it had done some practices, this was its 3rd gig, the first one was just a preamp out on a truck. The night before the bass wasn't in the PA and there were no real issues (I didnt Like the sound but I think that was unrelated). The first gig, the truck, I had to take it apart because the di socket was loose.

 

I think I might need to test it out at a few more practices and use the TC450 for gigs until I am sure

 

[agedhorse]

One of the biggest causes for intermittent failures of SpeakOn plugs is using non-Neutrik branded parts, or knock-offs or counterfeit plugs that are sold mail order as the real thing.

 

The second biggest cause, is the wires loosening up because the plugs were assembled incorrectly by tinning the wires. Never tin the wire of a pressure type connection, the solder will cold flow under pressure and loosen. This is actually addressed in Neutrik's OEM notes to manufacturers of cables. Of course, knock-off and off brand plugs probably won't have this information, in addition to being poor plugs.

[Chienmortbb]

1 minute ago, agedhorse said:

One of the biggest causes for intermittent failures of SpeakOn plugs is using non-Neutrik branded parts, or knock-offs or counterfeit plugs that are sold mail order as the real thing.

 

The second biggest cause, is the wires loosening up because the plugs were assembled incorrectly by tinning the wires. Never tin the wire of a pressure type connection, the solder will cold flow under pressure and loosen. This is actually addressed in Neutrik's OEM notes to manufacturers of cables. Of course, knock-off and off brand plugs probably won't have this information, in addition to being poor plugs.

100% and I cannot stress enough, tighten the screws as hard as you can.

[agedhorse]

No, do not over-tighten the screws, the maximum torque is clearly specified in the assembly instructions. Over-tightening of the screws distort the machined saddle assembly and can actually crack the material (or strip the threads if you don't twist  the had off the screw first). The screw can also cut the conductors in half if you d get it that tight.

 

https://www.neutrik.com/media/11062/download/bda-114---speakon-nl4fx--nl4frx.pdf?v=1

[Woodinblack]

I have two Neutrik speakon connectors (for why I got them, I can't remember), and about 4 speakon - speakon leads, and one Speakon to Jack lead (the ashdown CTM has jack socket outputs). 

Oddly enough, I have never made a speakon lead. Probably because before the TC cabs, all my cabs were jack. 

[Woodinblack]

Well, updated my beringer CT100 tester for a CT200, which now has speakons on it!

 

Seems like a couple of 4 way plugs with 2 wires.

[Bill Fitzmaurice]

Using only two poles of a four pole Speakon is common. You see it more in PA, but sometimes in amps. What's more common is two pole Speakon jacks on amps and speakers, used with four pole/four wire Speakon cables. You can use four pole cables with either two or four pole jacks, so if all the cables you carry are four pole you're not digging through the cable bin looking for a two pole cable.

[Woodinblack]

That is one of my 'directional' cables. 4 pole / 2 wire. They have a piece of tape at one end saying which end goes to the amp. They only work one way round.

I think I am just going to buy a load of 4 wire cable and rewire them as its one less thing to worry about.

[Bill Fitzmaurice]

Speakons should not have a direction. There are amps and cabs that aren't wired as they should be, forcing that arrangement. Odd how even some engineers don't know how to read applications charts. Frustrating to say the least, but c'est la vie.

[Downunderwonder]

5 hours ago, Bill Fitzmaurice said:

There are amps and cabs that aren't wired as they should be, forcing that arrangement.

I don't imagine a cab would come from factory with 1 and 2 shorted together but someone might have 'improved' it? It still wouldn't require a 1 to 2 speakon but would explain why the cable works only 1 way. Suspect doofus involved.

[Bill Fitzmaurice]

If it's a mono signal the +1-1 poles should be used on the amp output and speaker input. There are special circumstances where both the +1-1 and +2-2 poles might be employed, but you'd seldom see them utilized on a bass amp and speaker. It's fairly common with PA, using a dual channel amp and bi-amped speaker. The low frequency output of the amp and low frequency input of the speaker would go to the +1-1 poles, the highs to the +2-2 poles. Using a standard wired 4 pole 4 conductor cable it would be plugged into either amp channel output jack and into either input jack on the speaker, if it has two, and always be right.  Many's the HF horn that was blown using 1/4" plugging the LF output into the HF input.

 

[Woodinblack]

For reference, this was originally with a TC450 and 2xRH112 cabs, all brand new from the shop. I have now changed to an ashdown ABM600, the behaviour is the same. 

[Bill Fitzmaurice]

How they're wired should be in the owners manuals. If they're not wired +1-1 I can't say why. For that matter I'd expect they'd use 2 pole Speakons, so that would be the only option.