Grateful Dead Music Forum

A place to talk about the music of the Grateful Dead 

Chat about Equipment Info
 #57180  by gratefulnuge
 Wed Feb 25, 2009 3:55 pm
I've built myself a 3x12 cab with JBL E 120s....all 8 Ohm speakers...I have a Mac MC2105 Amp..105 W on each channel...more like 150 on each realistically. The tap options that I have are... 4, 8, 16 ohms...what is everyones opinion on the best Jerry sounding wiring schematic????...please let me know! thanks guys... - Nuge
 #57241  by philsaam
 Fri Feb 27, 2009 5:42 am
well try this--two spkrs in paralel --1 spkr alone --same cab ---with banana jacks on back ID the 1 spkr at 8ohms and the 2 spkrs at 4ohms ----run your mac in stereo select ohms for the 8/4 accordingly ---play with eq bassier for the 2-12 ch a higher middie---eq for ch b---then try this -----take the banana jack and piggyback it together on back of spkr box running all three spkrs in mono ---jack top banana to bottom ---run a mono signal from mac----set at 4ohms ---just watch your volume controls at all times ---dont blow your spkrs !!!-----look for a smaller mac a tube model Mc Intosh 60 --now there ya go ---You are so right about Mc Intosh power amps --I play bass through a Mac and its rated at 100 watts --I push a Gauss 15 -a Gauss 12--in seperate boxes 8ohms ea and a ampeg svt 8-10 classic the amp is on 4ohms out ---but with mac you get an autoformer to adjust for ohmage variances --as the pitch changes so does the ohms ---I have a tiny fan hooked up to blow cool air over the amp -an aux plugin whisper fan ------I hope I have been of some help to you my friend ---love our Mc Intosh amps --30+yrs plus service and no breakdowns here ---not bad!! you bet!! ta ta ---P
 #57298  by gratefulnuge
 Sat Feb 28, 2009 1:15 pm
Thanks a lot mac doesn't have an EQ setup on it...but I'll try the just wondering what you mean by watch my volume and do i know when im close to the blowing point? I don't play superrrrr loud gigs...just bars and stuff...lemme know...thanks a lot!!!
 #57438  by philsaam
 Wed Mar 04, 2009 1:35 pm
hello there my friend -----about volume --hummmm? every time you turn your amp on --both volumes off/ you will probably see your JBLs push out -this is an indicator of connection & phase ---both spearkers should move in the same direction -outward--youre in a paralell hookup so 2-8ohms are at 4ohms ---if you run your amp solely by your guitars output --measured in millivolts --maybe you have hot rodded your axe? it could be in volts -DC- listen to your speakers real good for signs of ------1] a wraspy burping distortion if your gain drives the cones to twist ---they extend outward [cones] until the suspension -tension from the spider ,the copper mesh you see attached to cone on the inside,---tension from spider limits the cones extension ---this is where with JBLs you must watch out for damage--JBLs have such beautiful fidelity their suspensions are a little soft and flexible -but you have extremely sensitive and -they are high quality ! -----------remember they move in and out----so if you have them in sealed boxes --good--make sure there is absolutely no dirt -or loose fibers -or dust from degraded insulation inside ---it could get sucked into the voice coil air gap --as it is your speakers will be working hard -----I prefer porting cabs {tuned ports] this helps in developing a stronger bass presence and helps keep speakers cool ----they get warm ---what doesnt turn into sound --turns into heat---speakers are held together with glue ----------I play bass and McIntosh amps are ----clean take it to the bank dependable--my old 2300 is in John Mc Vies possesion --Rick Turner brokered the sale --used on tour when Rumors was released---too much amp for me but --wow good power 1/2 ohm to 16 ohms 300rms ea ch ---with road case Tom Scully made for me {Alembic spkr cab maker back in the 70s] totalled out 150 lbs ------uh oh --hey I think you could push 2 Marshall 200 stacks --or Hi Watt---or Orange ---lots more speakers than the three you have to use set your amp carefully to the level you need --and if your not happy --get three more JBLs --or add 1 at a time to your array --there is heaven to be found in the choice you will make for that sound that will be unique to you --when you are happy --your fans will be too ----best of luck my good friend ----its all about the love ---go give it to em ! phil