how are the 2 x 8R speakers wired? series or parallel? TBH unless the bridged amps will work into 2R loads there are some problems here anyway.

I’ve seen claims some will but never liked the idea of doing such, ( i have a feeling this is also why “norfolk stacks” tend to sound a bit ropey). but I am old and grew up in the days when it was definitely not a good idea.

I’d check the cabling on all this lot and the impedances. you may need some custom cabling/leads. When I first started rigs had 1/4″ speaker jacks and/or even binding posts, though I’ve heard EU safety rules have stopped this as you can get a shock and also foreigners were using 4mm plugs for the 230V mains and all sorts as they “did that in their country when the Soviets ran the place”. To be fair though things looked sketchy these chaps (girls too, now I remember there were always more female sound engineers in foreign crews) didn’t mix up the audio and 230V as much as folk feared, no one anywhere in the world wanted to blow their speakers or electrocute their mates, they only did this due to a shortage of proper mains plugs!

Unfortunately haven’t done any serious pro audio stuff for years and when I did it was usually with crews where everything was carefully matched and they had loads of kit to go round and as I didn’t own a motor vehicle and still do not, would concentrate on getting the power to the rigs. The last link up I did power for, I had to take 3 x 100A feed off a former sewer pump circuit of a TPN distro and each rig got a 230V phase each. The mains cable used was as big as the service cable to my house!)

the reason they do not want a continusly low impedance is the power supply, in the 90’s the n most amp companies started to make big ams like they make car stereo’s loads of powerhandling but no condensators(a condensator is a coil or a battery like where power are stored to give you the extra boost you need) to follow it up…that means you really need big amps to get the power you want, due to lack of storage for low impedance output. The impedance of subs change all the time and in the lower specter frequencies it might be as low as 0,5 ohm, then if you have no condensators to follow that up, the bass sound turns slimey or is no where to be found…so when people ask what to do in these cases like this I say do a time travel and ask the big PA companies if the have some big ass amps with low watt but big condensators that only collecting dust in the back of their storage and ask to buy them……one example of low watt is the rate 4,4 to 1 that means to get a steady 100watts you need 440 watts power consumption to get those 100 watts, but then again you have a amp that can handle those low ohms…and probably play the arse of a modern amp…another good thing about old amps is they are not that in need if a very fine sinus curve to handle the the power current they are fed …and that means you have a easier job to get them to work properly out in field where you have only gennie power with a bad sinus curve work on….

(my own experience is that I/we have two old meyer subs, they need 2k of new amps each, but with a old amp I have made them work properly with only a 1200 (2×600) labgruppen from -89, and with extra cooling I can play flat-out with no distortion at all, next time I have my hand on this set up I will try to get all the specs. to illustrate a better way what I am talking about…)

@!sinner69! 476737 wrote:

(my own experience is that I/we have two old meyer subs, they need 2k of new amps each, but with a old amp I have made them work properly with only a 1200 (2×600) labgruppen from -89, and with extra cooling I can play flat-out with no distortion at all, next time I have my hand on this set up I will try to get all the specs. to illustrate a better way what I am talking about…)

for those slightly younger bear in mind our generation grew up literally with the birth of independent music and more portable pro audio equipment, and musicians directly working with the electronics engineers. Before that, pro audio was made to specifications of our big national broadcasters, and the post office telecommunications (as often it was so big and bulky it was installed in one place, and the sound brought to it over telephone lines). in those days the post office had monopoly control over all our communications!

however by the late 80s to mid 90s was when it became affordable for our generation to have good quality sound both at home and at events we attended. Much of this equipment was designed in the UK and Europe. For those who have some electronics knowledge, look for articles and books by John Linsley Hood. many are for smaller amps because the inefficiencies of design like class A mean you would have a great big electricity bill or bigger transformers and capacitors which make the equipment heavier…