speakers
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Topic: speakers
Posted By: target
Subject: speakers
Date Posted: Dec/31/2013 at 9:44pm
| For an am 8track the 74 tsm says the speakers are 3.2 ohm. Will 4 ohm work? I have always heard that using the wrong impedence speakers could damage the deck. Any opinions or thoughts? |
Replies:
Posted By: ramblinrev
Date Posted: Dec/31/2013 at 9:48pm
|
4 will work.
------------- 74 Hornet Hatchback X twins (since 1977) 62 American Convertible (still worth the $50 I spent in 1973!) AMCRC #513, AMO #384 70 AMX 360 4-speed (since 1981) |
Posted By: dltowers
Date Posted: Dec/31/2013 at 10:16pm
|
I have a 1974 Javelin with Motorola Multiplex AM Radio w/8-Track. It has the 4 speaker system (2 in each door and 2 in rear package tray). I recently put all new speakers in the car. Door speakers are 4 ohms and rear speakers are 8 ohms.   ------------- Original Owner, 1974 Javelin: 360ci,2v,727TC. Motorola Multiplex with 8-Track. G4 Plum exterior with 421Q Black Uganda Interior. Purchased on July 16, 1974 from Hooker AMC, Sherman, TX for $4500.20 |
Posted By: target
Date Posted: Jan/01/2014 at 5:50am
| The tsm says all speakers are 3.2 ohm. When I was a youngster we didnt know or worry about such things and just bought speakers. Hooked em up and if something burnt up just bought a new deck. As expensive as these are to repair and a pain in the butt to get out would just hope to avoid any problems from miss matched equipment. |
Posted By: dltowers
Date Posted: Jan/01/2014 at 8:41am
|
The speakers in my 1974 Javelin were the original ones that came from the factory.
When I replaced the speakers, I matched them to the same ohm rating as was marked on the originals.
The door speakers were 4 ohms and rear were 8 ohms.
The speakers I put in my car are very inexpensive, but they are perfect for a 40 year old radio.
The front speakers I bought from Ebay and the rear speakers from Wal-Mart.
** The front speakers need to be no more than 5.25 inches in depth, otherwise they will interfer
with the window mechanism.
Here are photos of my original speakers, you can tell that they have some 40 years wear/tear:
  ------------- Original Owner, 1974 Javelin: 360ci,2v,727TC. Motorola Multiplex with 8-Track. G4 Plum exterior with 421Q Black Uganda Interior. Purchased on July 16, 1974 from Hooker AMC, Sherman, TX for $4500.20 |
Posted By: dltowers
Date Posted: Jan/01/2014 at 8:54am
|
Correction to my above post:
The speakers diameter are 5.25, but the depth needs to be less than 3 inches to not interfer
with the window mechanism. ------------- Original Owner, 1974 Javelin: 360ci,2v,727TC. Motorola Multiplex with 8-Track. G4 Plum exterior with 421Q Black Uganda Interior. Purchased on July 16, 1974 from Hooker AMC, Sherman, TX for $4500.20 |
Posted By: target
Date Posted: Jan/01/2014 at 9:58am
| How could you tell the ohms of those speakers? What did the rear speakers look like? |
Posted By: dltowers
Date Posted: Jan/01/2014 at 10:26am
|
Rear speakers were in very bad shape, and I took no photos of them, but the marking on them were readable. They are the same 5.25 diameter as the front speakers, but had the 8 ohms markings on them. Does your car have a Speaker Fader Selector Switch (it should if it had 4 speakers from the factory)? The one on my Javelin is located on the lower right side of dash besides the steering column.The fader switch operates at 2 ohms impendance. Like I said, you can invest in more expensive/better speakers than I selected, but the AM Radio and 8-Track sound great with the speakers I bought and I am very satisfied. The door speakers were about $20 for the pair and the rear speakers were around $18 a pair. ------------- Original Owner, 1974 Javelin: 360ci,2v,727TC. Motorola Multiplex with 8-Track. G4 Plum exterior with 421Q Black Uganda Interior. Purchased on July 16, 1974 from Hooker AMC, Sherman, TX for $4500.20 |
Posted By: george w
Date Posted: Jan/01/2014 at 11:10am
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The rated impedance of a speaker is a nominal rating as the actual, working impedance ( resistance ) of a speaker varies considerably in actual operation. Virtually all impednace ratings are either a averaged rating or a minimum rating. The slight discrepancy between a 3.2 ohm rated speaker and a 4 ohm rated speaker speaker is insignificant. Furthermore, going to a higher rated impedance speaker such as an 8 ohm speaker where a 4 ohm speaker had been specified will NOT cause any harm to the radio or an amplifier. Going to a LOWER rated impedance speaker could ( but not always )cause an issue as the potential current draw of the lower impedance speaker could cause overheating of the radio's amplifier section under higher volume conditions as the lower rated impedance speaker will draw more current at higher volume settings. On the other hand, newer speakers ( as compared to the truly cheap, OEM grade speakers originally used ) are typically of much better design with vastly improved cone materials, more powerful ( not neccessarily heavier ) magnets and better voice coils which make the modern speakers more efficient. This means you get more output from the speakers from a given amount of input power from the radio's ampliifer. The net result is that the amplifier is likely to have it easier with a modern speaker that it did with the OEM junk irrespective of the new speakers rated impedance. Using a 8 ohm speaker where a 3.2 ohm or a 4 ohm speaker was used originally will mean that the radio's ampliifer will deliver less maximum power into the 8 ohm speaker. But... if that 8 ohm speaker is only slightly more efficient that the original 3.2 or 4 ohm speaker then the actual net effect on the radios maximum output level ( without distortion )may be an increase in usable output and certainly fidelity. My experience with the Motorola built AMC radios of the late sixties and early 70's is that they are are of low usable output power, in the order of 5 to 8 watts or so, for the mono radios and roughly the same power for each channel on the stereo radios. The amplifier sections of these radios is passable from a fidelity standpoint, but nothing approaching the high fidelity amplifiers that we how have in virtually all aftermarket and OEM car audio systems of today. If you want the OEM look then the best you can do, short of hiding another sound system in the car, is to use the stock radio with modern speakers that will fit into the original AMC factory openings and locations. Noisy and intermittent volume and tone controls on these older factory radios typically will respond to modest application of a volume control cleaner spray to the inside of the control. This requires that the radio be removed from the car and the cover opened so that the nozzle tube of the cleaner spray can be inserted into an opening in the "can" portion of the control so that spray can reach the resistance element and wiping contacts inside the control. Just a little spritz and some quick rotations of the control shafts are all that's usually needed to get the controls operating consistently again. If you're not familiar with such things then just remove the radio and take it to any tv or electronic repair shop. They'll know what to do. ------------- Long time AMC fan. Ambassador 343, AMX 390, Hornet 360, Spirit 304 and Javelin 390. All but javelin bought new. |
Posted By: target
Date Posted: Jan/01/2014 at 11:41am
| Wow George. Thanks! |
Posted By: uncljohn
Date Posted: Jan/01/2014 at 12:39pm
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To make it easy on myself I have been purchasing speakers from this source for my cars. What ever I have been looking for has been found here. https://www.onlinecarstereo.com/account/myaccount.aspx" rel="nofollow - https://www.onlinecarstereo.com ------------- 70 390 5spd Donohue 74 Hornet In restoration 76 Hornet, 5.7L Mercury Marine Power 80 Fuel Injected I6 Spirit 74 232 I-6, 4bbl, 270HL Isky Cam |
Posted By: dltowers
Date Posted: Jan/01/2014 at 12:41pm
|
Thanks George for the detailed information regarding speakers.
I had heard that using late/modern type speakers with old type radio
would cause the radio to over heat and draw excess voltage. ------------- Original Owner, 1974 Javelin: 360ci,2v,727TC. Motorola Multiplex with 8-Track. G4 Plum exterior with 421Q Black Uganda Interior. Purchased on July 16, 1974 from Hooker AMC, Sherman, TX for $4500.20 |
Posted By: 71 Javelin AMX O.O.
Date Posted: Jan/01/2014 at 2:33pm
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Everyone: Since you are on the subject of original speakers, I still have the factory front and rear set from my 1971 Javelin AMX. Since getting it back on the road the last two years I have not been happy with the sound. I am the original owner, also, and can't remember them being that bad? But we are used to a lot better quality, today. Anyway, the car has only 15,000 original miles on it and was inside stored for 38 years. Can these, like new speakers, be rebuilt to today's standards? I would like to keep the originality and have todays sound quality. Thanks Steve Original owner 1971 Javelin AMX |
Posted By: uncljohn
Date Posted: Jan/01/2014 at 3:36pm
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Today's speakers for todays radio's have features in them that I believe are not compatible with yesterdays radio's and you have to watch what you are buying. ' Many of the speakers today take far more power to just run them normally than the older ones did. and todays radio's have more power to do that with. The bottom line is more or less going to wallmart and buying what is on sale is no longer a viable approach. The lack of knowledge surrounding what is available and what can be used will lead you down a path you do not want to go. However compatible speakers are still available but the odds are going to an on line catalog source might very well be a better approach The ohms on a speaker is more or less o.k., if the speaker you are buying is more or less the same value and size. 3.2 = more or less 4 ohms. 8 ohms does not but the odds are nothing is going to happen catastrophically to your radio if you mix them up. These are old cars and driven rarely and radio's are rarely pushed to their max. The problem is new speakers with new statistics work with built in cross overs and some of those take a fair amount of wattage to run correctly. The out put of the older radios are about 6 to 10 watts per channel. An older speaker's ohm rating (4) or (8) will match up fairly well with what is available with more or less the same thing now and work. But purchasing a speaker rated at a very high wattage pretty much says it takes that much to run it correctly and your old radio only puts out about 6 or 10 or so. And sound quality may fall way off. And new radio's designed to run them that is those in newer cars have that wattage requirement. As far as keeping it original, that is a personal choice I guess, but a speaker that sounds good hidden behind the grill is worth a whole lot more than one that looks original but does not work and you can't see it because it is behind a grill. Just saying. I installed an old technology radio in my 1980 Spirit in 1999. I put in new technology speakers using factory mounting brackets last year. The were more or less the right ohms and the right size and low wattage ones meaning they were compatible with old technology radio's. The sound coming from them is a noticeable improvement. They can be found if you look. But walmart is generally not the place to look any more. ------------- 70 390 5spd Donohue 74 Hornet In restoration 76 Hornet, 5.7L Mercury Marine Power 80 Fuel Injected I6 Spirit 74 232 I-6, 4bbl, 270HL Isky Cam |
Posted By: george w
Date Posted: Jan/01/2014 at 8:47pm
|
Wow, quite a bit of input on this topic! An additional two cents worth is that virtually all speakers that you can buy today are superior in materials and design technology over the very basic speakers that AMC bought to use in their passenger cars through the 70's and maybe even later. Due to the superior materials used in most speakers sold today, they will be able to tolerate, and are rated at higher wattage levels, than our feeble OEM radios can produce. The fact that a modern speaker is rated to be able to withstand a higher wattage does not neccessarily imply that it will REQUIRE more wattage in order to produce a given volume level. In most cases today's speakers are more efficient than the small, Alnico magnet, paper cone speakers that the factory used. This translates into more acoustic output at any given wattage input. Keep in mind too that the impedance rating has nothing to do with the efficiency of a speaker nor it's power handling capability. It's strictly an electrical measurement of the speakers voice coil resistance. Typically 4 ohm ( more or less ) speakers ahve been used in cars as low voltage car amplifiers operating on 12 volts can produce more useable power into a 4 ohm speaker than a 8 ohm speaker. It's simple Ohm's law. The lower the resistance, the more current will flow at any given voltage. The more current that flows, then the higher the "power" developed in the load. Amplifiers only develop voltage at their output terminals. Apply this voltage to a load, like a speaker, and current will begin to flow. Take the current flow, which is measured in "amps". multiply it by the speakers impedance ( resistance in ohms ) and you have a "power" figure. Since the audio signal is varying rapidly and constantly the actual "power" delivered to a speaker is also always varying. Typically over a 5 to 1 to 10 to one ratio. Today's speakers have far better cone materials, typically will use a separate tweeter for high frequencies and have far stronger, more powerful magnetic structures that increase the electrical to acoustic efficiency. Even the smaller sized speakers today, like the 5-1/4" speakers frequently used in the front doors and rear hatch areas in cars like the Spirit hatchbacks, use separate tweeters or at least a "whizzer" cone tweeter for improved clarity and high frequency ability compared to the OEM single, paper coned speakers. AMC started upgrading the sound systems in the 80's using better speakers. For example, the later Grand Wagoneer's were available with the well known Jensen speakers in their "premium" sound systems. Nowadays "brand name" OEM sound systems have become commonplace with Bose being probably the most well known. JBL, Infinity, Boston Acoustics and even such high prestige audio brands such as Bang and Olufsen and B&W are now appearing across the spectrum in today's new cars. ------------- Long time AMC fan. Ambassador 343, AMX 390, Hornet 360, Spirit 304 and Javelin 390. All but javelin bought new. |
Posted By: uncljohn
Date Posted: Jan/01/2014 at 9:44pm
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[QUOTE=george w]. Due to the superior materials used in most speakers sold today, they will be able to tolerate, and are rated at higher wattage levels, than our feeble OEM radios can produce. The fact that a modern speaker is rated to be able to withstand a higher wattage does not neccessarily imply that it will REQUIRE more wattage in order to produce a given volume level. Unquote] This statement is true up to a point. As long as the speaker one chooses does not have any specific added features such as built in cross over circuitry, this is circuitry that steers or directs certain frequencys to itself and other speakers the speaker will indeed pretty much work with old school radio's. But unless you know what it is that you are looking at, a higher wattage rated speaker at say a 4 ohm rating will give you less output because in general that speaker is going to be designed to work with a newer and more complex radio. While price is not a real good indicator the cheaper speakers run the odds of working with an old AMC AM/FM radio or 8 track and work well. (QUOTE.) Apply this voltage to a load, like a speaker, and current will begin to flow. Take the current flow, which is measured in "amps". multiply it by the speakers impedance ( resistance in ohms ) and you have a "power" figure. Since the audio signal is varying rapidly and constantly the actual "power" delivered to a speaker is also always varying. Typically over a 5 to 1 to 10 to one ratio. (UNQUOTE) Watts = Volts X Amps. thus watts supplied to a speaker is the working voltage of the car, Maximum 12 volts times the amps the speaker will draw at any particular voltage of the signal that takes place across a 4 ohm load. OR Watts = amps (squared) X R where R = the value of resistance of the speaker X the value of the current that can be supplied by the source squared. That is the limits the radio can deliver. Both are basic formula's used in electronics to calculate the same thing for different reasons. If you have a high wattage speaker in your car being driven by an old school radio the odds are that speaker needs more watts supplied to it in order to function correctly and your radio just does not have the guts to supply it. It is far too easy to purchase the wrong speaker for an old school radio. Look for something that is priced at a lower level and avoid high wattage advertisement if you don't know what it means if you do know what it means this posting has no value for you so forget it. {Quote} Today's speakers have far better cone materials, typically will use a separate tweeter for high frequencies and have far stronger, more powerful magnetic structures that increase the electrical to acoustic efficiency. {Unquote} Absolutely true, a new tech inexpensive (relatively) speaker sounds a ton better. Buy the wrong speaker and you won't be able to hear it. You can if you carefully select a new tech speaker you can eliminate tearing up door upholstery and just put the 2 speakers in the rear package tray or the rear location in hatch backs or wagons. ------------- 70 390 5spd Donohue 74 Hornet In restoration 76 Hornet, 5.7L Mercury Marine Power 80 Fuel Injected I6 Spirit 74 232 I-6, 4bbl, 270HL Isky Cam |
Posted By: dltowers
Date Posted: Jan/02/2014 at 1:08am
|
Target,
You had asked earlier if I had a photo of the original rear speakers from my Javelin.
I did not think I did, but as I have kept all of the broken/replaced parts from the car's restoration,
I found one of my original speakers that was mounted under the rear package tray.
Below is a photo for your reference.
It is completely disintegrated, but you can still make out the part number
and the 8 ohm markings.
 ------------- Original Owner, 1974 Javelin: 360ci,2v,727TC. Motorola Multiplex with 8-Track. G4 Plum exterior with 421Q Black Uganda Interior. Purchased on July 16, 1974 from Hooker AMC, Sherman, TX for $4500.20 |
Posted By: 71 Javelin AMX O.O.
Date Posted: Jan/02/2014 at 7:51am
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George & Uncle John:
Your expertise in the speaker area is impressive. However you did not answer my basic question....can an OEM, orignal AMC speaker, be re-built to today's standards to get better sound quality? I understand the radio may not have the power to drive the newer speakers, but is there something that can be done to the orignal speakers to get them to sound better? Maybe I'm just deaming here and you may not know if this is possible? I appreciate all the discussion on this subject.
Steve
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Posted By: Mr. Ed
Date Posted: Jan/02/2014 at 8:10am
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George's info should be impeccable. That's what he does for a living. Has been for a very long time. Later! Mr. Ed ------------- 2014 Jeep Grand Cherokee Laredo "Gwendolyn." 1978 Concord Sport coupe "Mr. Black". 1982 Concord wagon. The Admiral. FOR SALE! 1976 Sportabout X, 304, auto, air. The Bronze Goddess |
Posted By: bigbad69
Date Posted: Jan/02/2014 at 8:31am
A speaker is nothing more than a moving coil which pushes air. The amplifier supplies the current to operate the coil. The speaker impedance must be matched to the design of the amplifier, otherwise, the amp cannot supply enough current which will give poor sound reproduction, or the amplifier could be overdriven, resulting in damage to the output stage. ------------- 69 Javelin SST BBO 390 T10 |
uncljohn wrote:Posted By: MattyCoupe
Date Posted: Jan/02/2014 at 11:28am
Yes, you can have your speakers rebuilt. They're a few places that do it. Orange County Speaker, Speakerlab, and Neil speaker repair are a few. Contact all three before you decide which to use. Make sure you go over your wants/needs with the reps, so they're no surprises on either side. OCS did my JBL concert cabinets and my original set of Kenwoods that my parents bought new before I was born. LOL. They did me good on both.
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Posted By: 71 Javelin AMX O.O.
Date Posted: Jan/02/2014 at 11:40am
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Matty:
Thanks for the recommendation. Were the results better than what you started with? Do you feel for the cost it was worth it?
Steve
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Posted By: MattyCoupe
Date Posted: Jan/02/2014 at 2:49pm
Steve, With the JBLs, Yes. They sound perfect, nice and crisp. With the Kenwoods, I didn't have anything to compare them to,the surrounds were rotted when I got them. but they sound amazing now! With the JBL, well worth the cost(1/3 the price of new set), with the Kenwoods, it was a sentimental thing.
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Posted By: 71 Javelin AMX O.O.
Date Posted: Jan/02/2014 at 2:53pm
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Matty:
One more question. Were the speakers for a vehicle or in home use? The names you stated sound like home speakers. I researched a radio restorers web site, Auto Electric and they state that you can't really re-build car speakers. When they tried the results were not up to the cost or quality expected. Seems like my idea of keeping my mint orignal speakers and getting better sound out of them, is not possible.
Steve
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Posted By: uncljohn
Date Posted: Jan/02/2014 at 2:59pm
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Yes old speakers can be rebuilt and or repaired, it is not rocket
science. But in general for an old car that in and of itself does not
have any increased value due to OEM style speakers being in it, why
bother and incur the expense when you can buy functional replacements. But it can be done here for one example and I am sure many others. http://www.heavysoundco.com/oldcarradiospeakers.html ------------- 70 390 5spd Donohue 74 Hornet In restoration 76 Hornet, 5.7L Mercury Marine Power 80 Fuel Injected I6 Spirit 74 232 I-6, 4bbl, 270HL Isky Cam |
Posted By: 71 Javelin AMX O.O.
Date Posted: Jan/02/2014 at 3:19pm
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Thanks Uncljohn, I'll give him a call and see what he says. His web site looks like he workes with old car speakers. The other companies were not that specific. Maybe I can get the oriognal sound back. He did state that tempuature can affect speakers and with -20 to +100 deg range here, they have experianced that!
Steve
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Posted By: george w
Date Posted: Jan/03/2014 at 7:03am
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There are places that can "rebuild" regular car and older radio speakers. Typically this is a "recone" job where the speaker's paper cone and voice coil are replaced with new. Parts are available for most of the popular sized, american made speakers of that era. In most cases the recone will restore the speaker to a close approximation of it's performance ( or lack thereof ) when new. A rebuild of this nature would not really be considered an upgrade however. There may be rare cases where the recone materials may be better than the OEM materials used, but not usually that much better. More modern "hi-Fi" speakers like the JBL/s and Kenwoods mentioned earlier typically are repaired by "re-foam" kits. This is where the speaker is otherwise OK but the rolled foam rubber outer cone suspension, called the "surround" had deteriorated and is replaced. The remaining critical parts like the speaker's original cone, voice coil and spider are left intact. This is a very common repair procedure for this type of high quality speaker. The smaller sized car speakers, like the 5-1/4" pincushion round speakers that AMC used, can usually be reconed but it's typically not done because it's not cost effective. These speakers used simple, pressed paper cones and were of low quality even by sixties standards. These speakers were nothing more than cheap, table radio grade speakers adapted for automotive use. Keep in mind that up through the mid 70's there still was a domestic table radio and home tv/stereo console manufacturing business that sourced their speakers from a handful of OEM domestic speaker maufactuer's that also supplied product to the auto industry. Jensen was probably the best known as they also succesfully manufactured and marketed upgraded aftermarket speakers in the popular 5-1/4 and 6 x 9 sizes. Everyone knew and wanted to upgrade to Jensen "Coaxials" at the time. Other well known domestic OEM speaker suppliers of the era were Rola, the OEM division of Jensen, CTS of Paduca Ky and Becker. I beleive that most of AMC's 5 1/4" speaker product came from Rola/Jensen. There's typically a 3 digit number stamped on the back of the speaker frames or magnet structures that designated the OEM manufacturer. Currently available aftermarket replacements typically will cost no more and are usually far better in materials and sound performance and are very reasonably priced. ------------- Long time AMC fan. Ambassador 343, AMX 390, Hornet 360, Spirit 304 and Javelin 390. All but javelin bought new. |
Posted By: 71 Javelin AMX O.O.
Date Posted: Jan/03/2014 at 8:41am
|
George:
I can see what your thought process is. Why spend money to restore when aftermarket replacements will not cost more and give better sound performance. I have to decide what I perfer. Originality and a little better sound, or go with a new speaker that has far better sound performance? I'll have to see what the rebuilder says. I know they want business, but you hope that he's honist.
Steve
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Posted By: amxdreamer
Date Posted: Jan/03/2014 at 12:16pm
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Steve, I purchased and aftermarket 4x10 for my AMX and covered it with grill cloth like the originals were done. You can't tell the difference from above yet the sound is "decent". This is from someone that competed in IASCA (car audio competitions) at a fairly high level (world finals twice - 7th and 9th). There are a few members here that work in the audio field or own shops, hopefully they can also provide some feedback. The speaker I installed was a 4ohm model so the factory AM/FM will actually be working a little less to power it. Plenty of volume but I barely turn the stereo on, I prefer to hear the music the car makes :) As you can see in this picture, I used the original wiring harness and installed foam etc. as per the factory and every bracket, screw etc was restored. http://s182.photobucket.com/user/amxdreamer2/media/amx%20car%20parts/SDC10545_zps3ac3e6d6.jpg.html" rel="nofollow">  ------------- Tony Vancouver, BC 1970 AMX 1972 Badassador AMO#10333 |
Posted By: george w
Date Posted: Jan/04/2014 at 6:20pm
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Nice job with the new speaker. One note though, if your original speaker was 3.2 ohms then the radio may be working a little less due to the slightly higher rated 4 ohm impedance of the new speaker. On the other hand if the OEM speaker was rated at 8 ohms then your radio could be working a tad harder as the 4 ohm speaker can draw more current from the radio's amp ( though I suspect you know this already with IASCA experience ). Your new speaker is likely to be more efficient than the original as well. Another advantage for the new. Somewhere in the late 70's to early 80's the speaker/audio industry "rounded up" the impedance ratings so the 3.2 ohm rating kind of went away and 4 ohm became the standard spec. Since the actual working impedance of a speaker varies rather widely one can assume that there's no functional difference between a 3.2 ohm and a 4 ohm speakers. It's kind of like when the auto industry went from gross hp ratings to the net ratings. The 3.2 rating was probably at or near the minimum rating for the speaker and the 4 ohm is likely the nominal rating. DC resistance will always measure a lower figure than the impedance rating. ------------- Long time AMC fan. Ambassador 343, AMX 390, Hornet 360, Spirit 304 and Javelin 390. All but javelin bought new. |
Posted By: amxdreamer
Date Posted: Jan/05/2014 at 3:04pm
Thanks, the speaker turned out well, the attention to details was big in competition back then and I guess it stayed with me. My post above stated the same info about the head unit not working as hard and potentially not providing quite as much output. "Back in the day" it was the big calculations to figure out how many subs of 4,6,8 ohm (single and dual voicecoil) you can install (stereo and mono) before the amplifier was maxed out. I was always amazed at the IASCA Nationals when looking at the factory demo cars and counting how many 1000W amps and 15" subs they had! ------------- Tony Vancouver, BC 1970 AMX 1972 Badassador AMO#10333 |
Posted By: sandmountainjeep
Date Posted: Jan/16/2014 at 10:31pm
| Great post George! Lots of good info on speakers and how they relate to old radios. |
Posted By: scguy390
Date Posted: Jan/17/2014 at 8:16am
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I've been looking for a replacement speaker for my '71 Hornet and found one at S&M Electro-Tech. You may want to Google it. ------------- 69 SC/Rambler 71 SC360 72 Gremlin < |
Posted By: DoughertyAMX
Date Posted: Nov/24/2020 at 5:34pm
Where can you get the grill cloth like you used, and is that just adhesive backed foam you used on top of the speaker mount to go between it and the dash?
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Posted By: tomj
Date Posted: Nov/24/2020 at 11:20pm
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Though decidedly non-stock, when I installed a 1976 radio into my 1968 American (the P.O. had botched up the hole with pliers and a hacksaw; I made an 18 ga black 'trim plate' to cover the atrocity) the radio wanted 8 ohms, and with that old 2N176 transistor driving it, I did not want to harm it. 8-ohm 6x8's or 5x7's or whatever it was being expensive, and because Rambler Mentality, I made a little carrier that attached to the speaker mounts that accepted two surplus Boston Accoustics 2.5" midrange drivers ($2.00 each from AllElectronics; I have a dozen of them) wired in series. HYUGE magnets, 8 ohms, radio happy. And of course invisible so only Grandpa Nash up in Heaven knows that I cheated. ------------- 1960 Rambler Super two-door wagon, OHV auto 1961 Roadster American, 195.6 OHV, T5 http://www.ramblerLore.com |
Posted By: amxdreamer
Date Posted: Nov/25/2020 at 12:10am
Any custom stereo shop should have cloth, yes that's just adhesive foam to replicate the original setup. ------------- Tony Vancouver, BC 1970 AMX 1972 Badassador AMO#10333 |
Posted By: S Curry
Date Posted: Nov/25/2020 at 8:52am
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Tony, I used the dual voice coil speaker like you. I just have an AM radio and series the coils together to the speaker output from the radio. I can't remember, but I thought it was 16 ohms per coil, series together would get you 8 ohms. I believe that is what the AM radio amp was looking for was an 8 ohm load. I used a grille cloth also. Keeps the junk from falling into the speaker cone and making it buzz. Make it short. Sounds great..... ------------- SC |
Posted By: george w
Date Posted: Nov/25/2020 at 10:21am
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If you connected the dual voice coils in series then the resistance (impedance) would be additive. If connected in parallel then the rating would be halved. Most likely the voice coils of the dual voice coil speaker are rated 8 ohms. If so, then a series connection would yield a 16 ohm load to the radio which would result is the speaker receiving less power from the radio though this would cause no harm to the radio itself. ( The higher the resistance of the speaker the LESS of a load it presents to the radio's amplifier ). You may not have enough volume however. On the other hand if each voice coil of the dual voice coil speaker is rated at 4 ohms then connecting them in parallel would yield an effective load of 2 ohms and this could very well be a problem for the radio In this case you'd want to series connect the coils together. Connect one conductor of the speaker feed wire pair to the negative terminal of the first voice coil. Then jump the positive terminal of that coil over to the negative terminal of the second voice coil. Connect the positive terminal of the second coil to the remaining conductor of the radio's speaker feed wire. Assuming the car radio is a mono, single speaker feed, radio, then it doesn't matter which wire goes to the negative terminal and which goes to the positive terminal when you're series connecting the dual voice coils of a single speaker together. It is important however that the positive terminal of the first coil is connected to the negative terminal of the second coil. In a parallel connection negative terminals of both coils are jumped together and positive terminals are jumped together. When doing a stereo, or multi speaker system, then the polarity and connections must remain the uniform between all the speakers in the system. ------------- Long time AMC fan. Ambassador 343, AMX 390, Hornet 360, Spirit 304 and Javelin 390. All but javelin bought new. |
Posted By: S Curry
Date Posted: Nov/26/2020 at 7:58am
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Like I say. I have the speaker spec's buried somewhere. Dual coil. If I remember correctly the '70 AM radio was looking for an 8 ohm load. Yes, parallel and series multiple coils will give you different impedance. All my notes are buried in storage and my memory is.....I know that the radio prolly sounds better then when it left Kenosha in Feb of 70. ------------- SC |
Posted By: dsm6678
Date Posted: Feb/12/2022 at 3:42pm
| Just getting ready to put new speakers in my 73 javelin. I have the parts manual and it is showing different part number for the speakers between 1973 and 1974. I also have the 1973 manual for the amc radio system for multiplex radios and they are saying 4 ohm speakers for front and rear but like I said 1974 parts book is showing a different part number for the speakers. |
Posted By: dsm6678
Date Posted: Feb/12/2022 at 3:51pm
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Hi dl towers. just got the oem type speakers for my 73 javelin, can you tell me what are the original screws used to install the speakers onto the rear shelf . Self tapping with the clips i am thinking something like this shown below, or do you just use self tapping screws directly into the original holes? Also which way are the connectors on the speakers supposed to face when installed? I mean do they face towards the front of the car or rear or inwards or outwards if you can remember? I ask because you can install the speaker with those facing different ways. My guess is towards the front so they are protected? thank you Darren
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Posted By: dsm6678
Date Posted: Feb/12/2022 at 3:54pm
dl towers pic ture did not come up here is the screw set i was asking about
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