New Build - T30s and then Otops to follow

[88h88]

I'm not sure what sussed means

Sussed = figured out.

[escapemcp]

It will be interesting to compare the voltmeter readings with what the amp thinks it should be putting out (allowing for the 1.141 multiplier - from the 3dB crest factor right? )


I reckon i have about 90% of the theory stuff on here sussed... even if i do sometimes use the wrong terminology!!... of course the more you know, the more you realize you don't know, so that figure can only go down!!!

I'm not sure what sussed means, but you're off to a bad start if you use 1.141 instead of 1.414.

That's a route to failure!

[escapemcp]

And back to the build...

My blown up amp was checked by the online shop I bought it from yesterday and they confirmed that there was indeed a fault on it and I hadn't blown it up by anything I did. At first they were saying that if I attached the amp to speakers that are 'too powerful', I could blow the amp - dunno if he was trying to refer to the low 4Ω impedance of certain PA speakers but sounded like to me. I was theerfore worried they might try to wriggle out of it. The only problem now is because they are a B-stock shop, they don't have any more iNukes in stock at the moment and they have no idea when they will be getting any more in They have offered that I can get anything else from the shop up to the value of the iNuke (=£280), but this is effectively a credit note... in English law it appears that they are not allowed to do this (I say appears as I am not a lawyer!) From the Office of Fair Trading leaflet about refunds:

Customers do not have to accept a credit note instead of a full refund, repair or replacement if the item is faulty; see Your customers’ rights on faulty goods. Where a customer is entitled to a full refund, repair or replacement you should not mislead them into thinking that a credit note is their only option.

Although there are other bits that they make this a grey area, thanks to so many different laws on this! I'm going to be getting back onto them to try to get a cash refund as I am so skint this month after having to buy an extra amp and other unexpected expenses. Failing that, they do have the DEQ2496 listed, although this is also out of stock... whichever comes into stock first, then I'm bagging it! I've been on their website so many times previously thinking "I'll have that", but when I have credit with them, I can't find anything I really want

Also done recently
Soldering up my Neutrik plugs last night, ready for install in the flight case. The red cable is an old Cambridge Audio phono to 3.5mm jack lead, but it was so stiff,, the 3.5mm jack ended up with a loose connection. I must have thought of slinging it repeatedly, but never did. Am so glad I didn't as it's perfect for my external 'in' lead for the flight case (as the back of the mixer will not be very accessible once it is in the flight case).


Second... here's that goddam analogue multi meter (YES, I'm getting a new one )


And finally (and probably most relevant), here's some shots of my almost completed V-plate:

The v-plate has been cut out as per the plans (although the plans are missing a few useful measurements on the v-plate, unlike the rest of the plans which have every measurement you could need on them). I then created a 'clamp' bit of wood that will grip the speaker in the horn mouth (the angled cut you can see in pics 2&3 are for allow for panel 7 as it approaches the panel 8 join). The tee nuts to hold the clamp to the V-plate are actually inside the clamp (as my 28mm handwheels wouldn't go through the entire assembly). Makes for a neater final look. The clamp itself is made up of a couple of bits of 12mm left over, sandwiching a 3-ish mm bit of scrap wood. I then cut holes in the 3mm scrap wood so that my handwheels would reach the tee nuts and also so that my tee nuts were gripping 12mm ply, rather than the 3mm offcut, which was a pretty shoddy bit of wood. This provided the space for the handwheels to tighten the whole way and still not be touching the bottom bit of wood of the clamp. So to install, I just have to put the v-plate on and line up with the holes in the clamp and tighten the handwheels. I did it this way, as I didn't want holes in the side of my sub! When the V-plate is 'installed' onto the speakers the clamp and the actual V-plate are flush to each other. I am worried that it *may* not be tight enough - it seems very snug at the moment, but may not be with ~600W running through the subs. I have 2 options in this case which are to either use another layer of weatherseal or to build another clamp. At the moment the 2 clamps are separate, but if I had to make another I would create a single 'L' clamp that runs along the 2 short sides of the V-plate - this can be created out of the 'other side' of the bit of the wood that you cut the V-plate from, thus squaring up your sheet of ply. When I say 'other side' I mean draw a square and draw a line from one corner to the opposite corner. One half of this square is the vplate and you could create the 'L' clamp from the other half. Hope that makes sense!

[escapemcp]

Does anyone here have experience of wiring up a digital spdif from a mixer (or whatever) in to the aes/ebu xlr in of the DEQ. I have seen some places say that you require a 220ohm resistor between a couple of pins on the xlr, others have a much more complex resistor network, yet the deq seems to have an option on the digi in to select aes/ebu OR spdif - which to me suggests it would accept a connection using only a phono to xlr lead. You know what they say about assumption, so has anyone here tried a similar thing pls?
Many thx

[Grant Bunter]

If you look at the input specs in your manual, you will see the input impedance for S/PDIF or AES/EBU is "approx 110 ohms" (vs the differing input impedance for the analogue inputs).

My understanding is you need a different lead for the digital connection, one designed for digital use, not an "ordinary" lead. The addition of resistors etc, may be an attempt to jury rig ordinary leads.
Check it out

edit: the AES EBU pre made leads I find locally are 110 ohm leads...

[sine143]

i've always used a normal rca connector to run digital out from a cdj2000 to the digital in on the djm series mixers. works a charm, comes in about 3 db hotter than the analog signal too.

[escapemcp]

i've always used a normal rca connector to run digital out from a cdj2000 to the digital in on the djm series mixers. works a charm, comes in about 3 db hotter than the analog signal too.

Isn't SPDIF 75ohm tho as opposed to the 110 of AES. Are they 'close' enough not to have to worry? Oh, hang on, Grant mentioned that both AES and SPDIF is 110 on the DEQ (which surely then makes it 'not quite SPDIF'). Reading up i have found out that the actual music data is the same and it is only the subcode data that is different.. some AES interfaces are happy to ignore the subcode, whilst others have a strop. Am guessing it is going to be suck it and see, but i was wondering if someone has already sucked it and seen?
I keep dreading the 'making own cables' option until i remember that i can now solder thanks to some tweeters and a couple of crossovers!

[MissileCrisis]

Whatever you do don't try coaxial RCA to SPIDF XLR patching into a behringer product, it has issues. If you go digital go all the way and get an xlr-xlr aes direct.

[Radian]

Are they 'close' enough not to have to worry?

No.

With a DEQ, patch in either using TOSLINK or AES/EBU.

If all you have is co-axial S/PDIF available ahead of the DEQ, then get a DI box to transform over to AES/EBU.

This is not something you want to hack. Digital communication failure mode is either "All Good" or "All Bad". There is no fuzzy in between area.

See here: http://billfitzmaurice.info/forum/viewt ... 28&t=19865

[escapemcp]

Whatever you do don't try coaxial RCA to SPIDF XLR patching into a behringer product, it has issues. If you go digital go all the way and get an xlr-xlr aes direct.

RCA is all I have coming out the back of the Behringer mixer. AES or TOSlink is all I have going into the DEQ

[escapemcp]

Digital communication failure mode is either "All Good" or "All Bad". There is no fuzzy in between area.

Yeah, which makes it funny when you see these audiophiles insisting on 'medical grade glass fibre' for 1m toslink cables!

See here: http://billfitzmaurice.info/forum/viewt ... 28&t=19865

Aah, that's what I was after... tried the search, but it always brings up too many results!

[Bill Fitzmaurice]

RCA is all I have coming out the back of the Behringer mixer. AES or TOSlink is all I have going into the DEQ

There are convertors.

[escapemcp]

RCA is all I have coming out the back of the Behringer mixer. AES or TOSlink is all I have going into the DEQ

There are convertors.

Yeah, that's the (new) plan... a bit annoying as really i need to fit the convertor into my flightcase as I'd rather have any runs in AES rather than SPDIF, and it is starting to get a tight squeeze in there - I'll just have to ram it in!

[Bruce Weldy]

RCA is all I have coming out the back of the Behringer mixer. AES or TOSlink is all I have going into the DEQ

There are convertors.

As I've never used digital linking......for those of you that have - Is it really even noticeable in a live sound or DJ setting?

There are all kind of signal paths going on here besides the board to the processor - processor to amp, amp to speakers. These aren't digital.

No to mention all of the typical setup parameters that need to be done correctly in order for you to get "good" sound.

Can anyone truly say that in an AB test under live conditions - you could tell the difference?

Or is this like putting racing slicks on your Neon.....looks better, but doesn't run any different.

[Grant Bunter]

'medical grade glass fibre'

I've worked in the medical profession for over thirty years (including operating theatre and intensive care units) and never even heard of that!
People will do anything to charge more...