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RS 4.5 Info Advice Needed

I also plan on getting a active crossover not sure which one yet

Might still recap the existing crossovers since separating the EMITs and the EMIMs seems to require cutting wires.
Click to expand...

Do you plan on using another amp to Tri Amp?
If you did this why would you need the speakers passive crossover at all?

Likewise the Watkins woofer. There is a crossover just on the bass to drive separately the 4 ohm and 2 ohm coils.
Click to expand...

I ran this circuitry thru CircutMaker and it is interesting to see what is happening here.
Basicly the 2 Ohms VC is used for the very low freqs and will draw massive current.
There is a Phase shift between the two coils also.
I am not a expert here just noting what I have seen.

I have some concerns here as the 4.5s have two of these 2 Ohm VCs
wired in paralel and this means the amp will see 1 Ohm

I was thinking about this If this gives me grief I can try a couple things

1) rewire the 2 Ohm VCs in series. downside this will cause a shift in the freq resp of the low end
as the LCR circuit is tuned to the 2 Ohm impedance of the Voice Coils in paralel 1 Ohm.
Would need to change coil and cap values.

2.) Use two amps for the lows basicly drive one woofer per amp
rewire the crossover to be like for example the RS 2.5 or one of the
Quantum series

3.) Just get an amp that can drive 1 Ohm.....

4.) Use the bass cut switch this adds .9 Ohms to the circuit
this will cause the circuit to shift up in freq response.
 
I considered the tri-amp option and using a Class A SS unit for the treble but that seemed like overkill and I doubt I would hear the difference. A good tube amp for the EMIT/EMIMs would be a better bet although more expensive.

I studied the bass crossovers and was a bit befuddled but thought the 2 ohm had a bandpass filter - inductor and cap (from memory.)

I knew the bass was very low impedance so picked out the Sony amp to match. According to TVK, it has 1 ohm ratings!

I think I'm done with the crossovers for now. The next tweak is to line the insides of the box with Dynamat and add more internal bracing. The RS 4.5 could really use that with dual woofers. One might even add a new MDF panel on the rear with a layer of Dynamat as a constrained absorber. I also found that the metal control panel on the top rattles - Dynamat there might fix that.

I've already added hardwood buttons on the bottom to mate with my concrete garage floor but I might upgrade to big spikes too.

BTW, looked at the Infinity active crossover box and was not impressed. The Rane or equals seem a better solution and much cheaper.
 
Well here is some pictures on the packing of the RS 4.5s looks pretty good

Here is the email I got with the images

Here is the speaker that got packed yesterday/this morning, still one more box
to add to this one but you can see from the different photos how I've built it
out using Sheet styrobaord, It is finally wrapped in 7 ply card board, heavy
corner boards are used and then the boxes, Will finish the second one which is
about 3/4s of the way done - as soon as my helper (15 year okld son) gets
here, the Grilles will be last , I got some excellent boxes for those as well. One
more trip to Home Depot for more sheet styroboard, you wont regret it!!

Stay tuned,
 
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Yup looks like he knows what he is doing. It looks like a small refrigerator being shipped when he's done :D
 
I am wondering if anyone knows how many RS4.5 RS 4.5 were made? I read somewhere 300 pair but that seems too low.
 
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Here I am with the 530 lb. crate containing the RS4.5. I want to open it, but they are safest intombed until my listening room is finished. Hard to wait!!

Second pic betrays my patience level. Just a peek. This packing job is on crack! I had to remove 3 sheets of 1" styrofoam just to get to the shrink wrap.
 

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Now THAT'S the way to ship speakers! Looks like a great packing job.

We're getting a pretty nice club of 4.5 owners here.

David
 
Update on the RS 4.5s after a lot time and effort by John in Ontario this is the result

Message: Jerry, Its been noted that your picking them up, ETA is Friday, They have your cell, Total weight of 400lbs!! Ouch!
-----------------------------------------------------------------------

Estimated delivery Jul 27, 2007
Service type FedEx Freight International

Tracking results as of Jul 25, 2007 6:47 AM CST

Date/Time Location/Activity
Jul 23, 2007 6:58 PM OTTAWA, ON/Picked up
6:58 PM OTTAWA, ON/Transfer

Well today is my Birthday I bought my self two nice presents a
Soundcraftsmen RA7502 from Tom (zenithradio) Man is this amp mint
and the RS 4.5s are in country and will be here on Friday
just in time to enjoy on the weekend
 
goat67 There is a rule that ALL Infinity 4.5,s stay Canada. They are never allowed in the States. :no:
 
Nice speakers!!!




phaedrus said:
I use the Infinity crossover, and run a pair of SAE X-25 (250 watts/8 Ohms) amps. If you want to vertically biamp, you'll need identical amps for the left and right. I'm not familiar with the Soundcraftsmen, but, assuming those are two different amps, I would expect you would need to run them horizontally biamped. You can do so either with or without a crossover; the Infinity manual has diagrams of all the various options for setting them up.

Just my $0.02 worth; I am sure Vito will be along shortly and can give you the authoritative answer.

David
Click to expand...

The Soundcraftsmen RA7503, RA7502, and RA7501 are all the same amplifiers. The only differences between them are that the 7503 has a spectrum analizer and power meters, the 7502 has only the power meters, and the 7501 has no meters at all.

You could vertical bi-amp them with no problems at all. An outboard electronic crossover would be a very nice upgrade if you could get ahold of one...
 
SleeperSupra said:
Nice speakers!!!






The Soundcraftsmen RA7503, RA7502, and RA7501 are all the same amplifiers. The only differences between them are that the 7503 has a spectrum analizer and power meters, the 7502 has only the power meters, and the 7501 has no meters at all.

You could vertical bi-amp them with no problems at all. An outboard electronic crossover would be a very nice upgrade if you could get ahold of one...
Click to expand...

On the amps yes I know what the differences are. I have two RA7502s and an RA7501 and a MA5002

I plan on trying out vert BiAmp I am Horiz Bi Amping my RSIIBs currently.
Yes I will get an external active crossover still deciding which one.
 
There here..................

Got the grills unpacked takin a pizza and beer break next is the speakers boxes came in one piece keep you all posted
 
Well one unpacked looks fine had to move the RSIIBs out. I will find them a home no worries. Got out the olive oil and gave it a good rub. Now time to move it into its home see ya..............
 
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