AR-3 & AR-3a Where's the Bass?

[Guest leopoldstotch]

Hi all. I need a little help getting to the bottom of something. I have a pair of AR-3's & AR-3a's. Both pairs of speakers are putting out what sounds to me like mid-bass from the woofers and not a low growling bass like I have read other describe on this site. In all actuality the bass is anemic. What could be the cause of this? I have tried the speakers in two different setups to no avail. The surrounds on the woofers are in excellent shape. Any suggestions? Thanks!

[dynaco_dan]

Hi Bruce;

You want growling bass?

Most recorded music does not have any real deep bass, below 50 hz..

Your sound source must have the low bass tone.

A few brief samples are, Casper, The Friendly Ghost soundtrack, Also Sprach Zarathustra, and Patriot Games soundtrack.

I have filed away a list of cd's that I posted here a few years ago.

Massive Attack has a few room shakers.

I'll be getting to my cd collection in the next month or so to comment more intimately.

Other members will definitely add to this short list.

Also Sprach Zarathustra has a 32 hertz growl at the very begining of that cut.

This is assuming that you have a very decent amplifier, perhaps 100 watts RMS or much greater for this particular cut.

The impedance rises in the deep bass of the AR 12" woofer, upwards of 35 ohms.

An amplifier with 200 watts RMS at 2 ohms and 30 watts RMS at 8 ohms may not have even 10 watts at 35 ohms.

You may have read where I comment on having an AR amp and Crown DC-300A/IC-150 and test driving a pair of my AR-3A's.

With the same, can't remember the music title, it was not a special bass test anyways, song being played at only moderate levels.

With the AR amp I was pleased that my system was pretty good sounding.

Connecting up the Crown amp setup gave a more solid bass that I also felt, stomach massage and all, in another part of the house.

I still recollect this momentous experience, 30 plus years later, it had that much of an effect on me.

My budget did not allow me to even consider the $1,200.00 CDN outlay at that time.

I can't comment on the attack and decay or the combination but it was very much improved.

That Crown set went back to the store a few days later, poor WAF, a mated set was re-created 20 years later.

This improvement was noticeable within the first minute or less of use.

I must have been really pouting when I had to return these fine pieces of equipment.

At a friends home who had Quads and a single AR-3, using the woofer only, Also Sprach was making me feel sick to the stomach, until the tone stopped, then I felt a relief.

The room was about 15 x 30 feet in size or larger.

This was using a Dynaco Stereo 70 amplifier to drive the AR-3, probably in combined mono output.

As Frank has correctly pointed out next, and I had assumed, correct room placement, good cables and fuses are another good investment.

[frankmarsi]

>Hi all. I need a little help getting to the bottom of

>something. I have a pair of AR-3's & AR-3a's. Both pairs

>of speakers are putting out what sounds to me like mid-bass

>from the woofers and not a low growling bass like I have read

>other describe on this site. In all actuality the bass is

>anemic. What could be the cause of this? I have tried the

>speakers in two different setups to no avail. The surrounds on

>the woofers are in excellent shape. Any suggestions? Thanks!

Look at your room placement, and certainly your amps power, and quality of the program material.

FM

[onplane]

It's possible, but not likely, that the mid driver is over powering your woofers.

Why don't you just remove the strap and power just the woofers by themselves.

You should be able to tell if the woofers are growling without the interference of the other drivers. Further, if the bass is still weak, try a different amp.

Regards,

Jerry

[dynaco_dan]

Hi again Bruce;

What amplifier are you using?

Check that your present speaker wires are wired in phase.

[Guest leopoldstotch]

The amp I'm using now is a Sansui 8080DB rated at 85 watts per channel. I have also used an NAD 912 amp rated at 30 Watts per channel along with an NAD 712 receiver rated at 25 watts per channel. I have also done what Onplane has suggested and tested both pairs of speakers in woofer only mode and the bass(or lack thereof)is just missing. there is just no bass at all coming from the woofers and I just can't figure out why.

[Guest matty g]

Hi -

First off, ditch the NAD units - they don't have enough power to truly drive those speaker systems without clipping out early. This WILL damage the speakers sooner or later. Second; absolutley double and triple check the speaker wire phasing. If both the AR3 and 3a systems sound funky,this is the most likely suspect. An 8080 receiver is more than capable of producing amazing sound through those speakers. Is it possible that the accoustic seal has been disturbed on them? Are they all the original woofers? Terminal 2 should be tied to the red or + of the amp and terminal 1 to the black or - of the amp.

Hope this helps - that's one complaint I must say I've never heard about those fantastic loudspeaker systems!

Matt

[Guest leopoldstotch]

>Hi -

>

>First off, ditch the NAD units - they don't have enough power

>to truly drive those speaker systems without clipping out

>early. This WILL damage the speakers sooner or later. Second;

>absolutley double and triple check the speaker wire phasing.

>If both the AR3 and 3a systems sound funky,this is the most

>likely suspect. An 8080 receiver is more than capable of

>producing amazing sound through those speakers. Is it possible

>that the accoustic seal has been disturbed on them? Are they

>all the original woofers? Terminal 2 should be tied to the red

>or + of the amp and terminal 1 to the black or - of the amp.

>Hope this helps - that's one complaint I must say I've never

>heard about those fantastic loudspeaker systems!

>Matt

Matt,

The speaker wires are phased correctly and they are sealed perfectly. The woofers are the original ones. I don't understand it either Matt. It makes no sense that these speakers are experiencing a lack of bass.

[soundminded]

Frankly, there aren't many possibilities. Here are my candidates in order of likeliness.

Forget the NAD receivers, they are too puny. The Sansui receiver should do the trick.

1. There is an air leak one way or another in the speakers. With power off, when the cones are depressed gently, they should spring back slowly. If they do not spring back, there is a leak.

2. The speakers are out of phase. Either externally or internally. When the speaker surrounds were replaced, the drivers were incorrectly wired when they were re-installed or the wires between the speakers and amplfier are not the same between the two channels, try reversing connections at the speaker to one channel only.

3. The Sansui receiver is malfunctioning. Possibly power supply problems. The filter cap may need replacement although this problem is usually accompanied by a hum.

4. The source is defective or not putting out truely deep bass. There is a peculiar mismatch between the source and the preamplifier (very unlikely.) Is the sorce a phongraph cartridge? Is it connected to a microphone or other incorrectly equalized input such as a tape head input? Try a CD player, even a cheap one puts out tremendous bass.

5. The speakers are located in a bad acoustic location. If you put these on stands in the middle of a room away from a wall the way many speakers are installed today, their bass will be considerably attenutated. Try placing one on the floor in the corner of a room and switch the receiver to the mono mode with the balance control at its extreme setting. Switch on the loudness or contour control and advance the bass control. Be certain the tone controls are in the circuit. If this doesn't work to substantially increase the bass in any of them, in all likelihood all four woofers are somehow damaged. Good luck.

[dynaco_dan]

Hi again;

Is your grille cloth off?

Do not remove them at this time, you can see through the grille cloth with a flashlight for now.

This is the same complaint with the AR-3 and AR-3A?

This is too much to be 4 blown woofers, but not unheard of.

The 85 watts is at what impedance?

It should be adequate for this meager test.

All of them should be ok for this minor trouble shooting adventure.

For on-going use the larger amp will be likely enough power if you can find us the specs.

Can you, testing just the woofers only, see back and forth movement of the cones with some bass, not boosted bass either.

Do not boost the bass or use the loudness control, this is an invitation to do further damage.

Let us know further, please.

[Guest leopoldstotch]

>Frankly, there aren't many possibilities. Here are my

>candidates in order of likeliness.

>

>Forget the NAD receivers, they are too puny. The Sansui

>receiver should do the trick.

>

>1. There is an air leak one way or another in the speakers.

>With power off, when the cones are depressed gently, they

>should spring back slowly. If they do not spring back, there

>is a leak.

>

>2. The speakers are out of phase. Either externally or

>internally. When the speaker surrounds were replaced, the

>drivers were incorrectly wired when they were re-installed or

>the wires between the speakers and amplfier are not the same

>between the two channels, try reversing connections at the

>speaker to one channel only.

>

>3. The Sansui receiver is malfunctioning. Possibly power

>supply problems. The filter cap may need replacement although

>this problem is usually accompanied by a hum.

>

>4. The source is defective or not putting out truely deep

>bass. There is a peculiar mismatch between the source and the

>preamplifier (very unlikely.) Is the sorce a phongraph

>cartridge? Is it connected to a microphone or other

>incorrectly equalized input such as a tape head input? Try a

>CD player, even a cheap one puts out tremendous bass.

>

>5. The speakers are located in a bad acoustic location. If

>you put these on stands in the middle of a room away from a

>wall the way many speakers are installed today, their bass

>will be considerably attenutated. Try placing one on the

>floor in the corner of a room and switch the receiver to the

>mono mode with the balance control at its extreme setting.

>Switch on the loudness or contour control and advance the bass

>control. Be certain the tone controls are in the circuit. If

>this doesn't work to substantially increase the bass in any of

>them, in all likelihood all four woofers are somehow damaged.

>Good luck.

Maybe this will help us trouble shoot this further the woofer sounds just like it's a full range speaker i.e. I 'm hearing vocals and guitars coming out of them albiet it's a bit muddy. Is it possible that the crossovers are shot?

[soundminded]

STOP THE MUSIC!!!!!!!!

The speakers have been rewired internally....incorrectly.

WARNING WARNING WILL ROBINSON. DANGER DANGER DANGER DANGER!

Incorrect wiring of the speaker system risks severe damage and destruction to the midrange and tweeter. Do not operate until this problem has been fully investigated and resolved. Cross your fingers that this has not happened already. Read my posting on the impedence of AR9 to understand the crucial role of the crossover network and why miswiring a speaker system can destroy the drivers.

[Guest matty g]

Hi again -

Well, the only other suggestion that I can come up with that hasn't been mentioned here is that all four speakers have been damaged by underpowering them with the smaller NAD amps, but you would have heard quite a bit of distortion for a while before cooking the woofers. The internal phasing can be checked by touching a flashlight battery (aa or aaa) for an instant to the terminals on the back of the cabinet while looking through the grill cloth. If the cone of the woofer moves out when the battery is touched to the terminal (assuming 2 is to the + of the batt. and 1 is to the - of the batt.)then the internal wiring is phased correctly. Just touch the battery for a half a second at a time to avoid damage to the drivers.

Hope this helps and good luck!

Matt

[soundminded]

The woofers are extremely robust and cannot be damaged by underpowering them. They are only vulnerable to damage when they are not in sealed enclosures and are driven to the point where their voice coils bottom out. It's analagous to revving an engine at high RPM in neutral, the engine has nothing to work against. In their enclosures they are rated to handle 100 to 200 watts RMS continuously and laboratory tests show they can handle impulse bursts of over one kilowatt without damage. Miswring the crossover network where the midrange and woofer connections are inadvertently reversed risks destroying the midrange drivers and the woofers will put out no bass frequencies at all. If someone has gotten inside of them already such as disassembling them to replace rotted woofer surrounds, anything is possible. The AR3 woofers are most likely cloth surrounds. Some of that XL-49 sealant from Orange county speaker company may be useful if the cloth surrounds have become porous. The surround material was changed during the AR3a production runs as I recall. Perhaps someone like Tom can clarify this. I do not know if the AR cloth surrounds rotted the way the foam surrounds did. In KLH they didn't but they could become porous creating an air leak and reducing bass output. However, the fact that midrange sound is coming from the woofers of AR3a is very troubling. The crossover point was either 525 or 575 hz in that speaker, an octave lower than AR3. It is possible that someone somewhere along the line rewired them incorrectly after they left the factory. Anyone can walk into Home Depot and buy a screwdriver and into Radio Shack and buy a soldering iron. No license or test is required.

[Guest leopoldstotch]

>STOP THE MUSIC!!!!!!!!

>

>The speakers have been rewired internally....incorrectly.

>

>WARNING WARNING WILL ROBINSON. DANGER DANGER DANGER DANGER!

>

>Incorrect wiring of the speaker system risks severe damage and

>destruction to the midrange and tweeter. Do not operate until

>this problem has been fully investigated and resolved. Cross

>your fingers that this has not happened already. Read my

>posting on the impedence of AR9 to understand the crucial role

>of the crossover network and why miswiring a speaker system

>can destroy the drivers.

Well I've had a look inside the cabs and the wiring is correct. I verified this with the schematics. The AR-3 Caps have an April 25, 1965 dated stamped on them and my AR-3a woofers have a date of Sept 1973. Seeing that both pairs are wired correctly I'm really scrathching my head here.

[soundminded]

Well, I've run out of ideas. Maybe someone else can come up with a better one which will help. Short of taking it to someone experienced in repairing this type of speaker, I've got no other suggestions.

[ar_pro]

You have plenty of power with which to evaluate your speakers - the Sansui is fine.

If the crossover is wired properly, and the coil is OK, low bass ouput could be a cooked woofer.

Phasing is irrelevant, if you test one speaker at a time.

Do you have access to an audio generator, or a CD with test tones?

Start at 200 Hz, and work down (go easy on the volume). The AR-3 woofer should give plenty of output below 50Hz.

[Guest leopoldstotch]

>You have plenty of power with which to evaluate your speakers

>- the Sansui is fine.

>

>If the crossover is wired properly, and the coil is OK, low

>bass ouput could be a cooked woofer.

>

>Phasing is irrelevant, if you test one speaker at a time.

>

>Do you have access to an audio generator, or a CD with test

>tones?

>

>Start at 200 Hz, and work down (go easy on the volume). The

>AR-3 woofer should give plenty of output below 50Hz.

>

>

>

>

>

>

Yes I do have access to a CD with test tones. I'm going to go to Radio Shack and buy an SPL Meter and test the woofers. I haven't checked the woofer coils but what should I do to test them? Thanks!

Well I have jsut done an inital test without an SPL Meter and I have plenty of Bass output from 200 Hz all the way down to 30-39 Hz and boy can those woofers sound really good. The question remains as to why they sound like a full range speaker then.

The best I can tell you about the Sansui 8080DB is that the output is 85 Watts per channel RMS into 8 ohms. I know on the back of the receiver it says the speakers should be 8 ohms.The Sansui says nothing about using 4 ohm speakers so could this be the issue?

[dynaco_dan]

>The woofers are extremely robust and cannot be damaged by

>underpowering them.

Hi there;

These are very, very robust woofers, in a pefectly acoustic sealed enclosure, but the voice coil CAN be burnt by underpowered amps, I know and have seen this toasted damage first hand, too many times, sadly.

I am not trying to start a debate here just stating a fact, that I witnessed many times.

I saw this with AR and particularly Dynaco woofers, all too often.

The Dynaco SCA-80 integrated S/S amp seemed to be that most used amp here at the time I saw the damage.

This was the two larger speaker companies, that had their warantee repairs done at a local repair shop that I was happy to work at for a few years.

They are only vulnerable to damage when

>they are not in sealed enclosures and are driven to the point

>where their voice coils bottom out.

Bottoming out of the woofer, can easily be accomplished by turning the volume up full and dragging a finger across the stylus, or dropping the arm, for just two examples.

This is one definite no-no in hifi and guarantees damage, to say the very least.

I cannot comment whether a 1,000 watt RMS per channel or greater amplifier will, if kept below clipping, burn the voice coil or not, with normal music.

I believe it is at the Crown site, that I read, temperatures measured at the dust dome of around 150+ degrees celcius.

I suspect your Sansui may have a low tolerance of lower loads than 8 ohms and not much steam at the higher impedance of about 35 ohms as well.

As far as the woofer goes much, much more amp power is needed.

The rated speaker impedance is usually taken at 1khz, the woofer and mid are neck and neck with the AR-3 and primarily the mid with the AR-3A.

This will still not stop a reasonble sound level.

In fact if you do not expect too much overall, unless they are defective, should provide not the best sound, but adequate sound, use any of your amps.

With the lower amps output, you will not be able to enjoy all the output capabilities that these very fine AR speakers can reproduce.

If you need to turn the volume control past 12 o'clock you are either too loud or asking too much from them.

AR recommended a minimum of 25 watts RMS for the typical room.

They were not nitpicking but it can be interpreted now that this was not at their rated 4 ohms but from 4 ohms to 35 ohms to be realistic.

They also said that for a larger room, maybe double that rating.

This will shed a different light on amplifiers output that were available during the introduction of their AR-3 speaker system.

Most, if not all amplifiers, were of the tube type.

Low power, low damping factor.

I believe that I've read in old AR literature, there would be no improvement to a 12" woofers performance, if an amplifiers damping factor was around 5 and raised in any great amount.

Based on the equipment and experiences that Edgar Vilchur had at that time, was not a mistake, he just did not know what was coming down the road.

I believe I've expressed my opinion many times of my Crown DC-300A versus AR amplifier in one only home comparison many years ago.

A friend found that he was well rewarded with a Phase Linear 700B amplifier with AR-LST's.

Frank has expressed his opinion already and he uses Phase Linear 400's with his AR-LST's.

The AR amp put out 60 watts RMS per channel 20 - 20,000 hz but was tested commonly at 100 plus watts in reviews, very conservative rating by AR.

The amp put out about 35 watts per channel at 16 ohms 20 - 20,000 hz but one can only guess, at the 35 ohms bass impedance, what the amp may have been able to put out.

[Guest leopoldstotch]

>>The woofers are extremely robust and cannot be damaged

>by

>>underpowering them.

>

>Hi there;

>

>These are very, very robust woofers, in a pefectly acoustic

>sealed enclosure, but the voice coil CAN be burnt by

>underpowered amps, I know and have seen this toasted damage

>first hand, too many times, sadly.

>

>I am not trying to start a debate here just stating a fact,

>that I witnessed many times.

>

>I saw this with AR and particularly Dynaco woofers, all too

>often.

>

>The Dynaco SCA-80 integrated S/S amp seemed to be that most

>used amp here at the time I saw the damage.

>

>This was the two larger speaker companies, that had their

>warantee repairs done at a local repair shop that I was happy

>to work at for a few years.

>

>They are only vulnerable to damage when

>>they are not in sealed enclosures and are driven to the

>point

>>where their voice coils bottom out.

>

>Bottoming out of the woofer, can easily be accomplished by

>turning the volume up full and dragging a finger across the

>stylus, or dropping the arm, for just two examples.

>

>This is one definite no-no in hifi and guarantees damage, to

>say the very least.

>

>I cannot comment whether a 1,000 watt RMS per channel or

>greater amplifier will, if kept below clipping, burn the voice

>coil or not, with normal music.

>

>I believe it is at the Crown site, that I read, temperatures

>measured at the dust dome of around 150+ degrees celcius.

>

>I suspect your Sansui may have a low tolerance of lower loads

>than 8 ohms and not much steam at the higher impedance of

>about 35 ohms as well.

>

>As far as the woofer goes much, much more amp power is

>needed.

>

>The rated speaker impedance is usually taken at 1khz, the

>woofer and mid are neck and neck with the AR-3 and primarily

>the mid with the AR-3A.

>

>This will still not stop a reasonble sound level.

>

>In fact if you do not expect too much overall, unless they are

>defective, should provide not the best sound, but adequate

>sound, use any of your amps.

>

>With the lower amps output, you will not be able to enjoy all

>the output capabilities that these very fine AR speakers can

>reproduce.

>

>If you need to turn the volume control past 12 o'clock you are

>either too loud or asking too much from them.

>

>AR recommended a minimum of 25 watts RMS for the typical

>room.

>

>They were not nitpicking but it can be interpreted now that

>this was not at their rated 4 ohms but from 4 ohms to 35 ohms

>to be realistic.

>

>They also said that for a larger room, maybe double that

>rating.

>

>This will shed a different light on amplifiers output that

>were available during the introduction of their AR-3 speaker

>system.

>

>Most, if not all amplifiers, were of the tube type.

>

>Low power, low damping factor.

>

>I believe that I've read in old AR literature, there would be

>no improvement to a 12" woofers performance, if an

>amplifiers damping factor was around 5 and raised in any great

>amount.

>

>Based on the equipment and experiences that Edgar Vilchur had

>at that time, was not a mistake, he just did not know what was

>coming down the road.

>

>I believe I've expressed my opinion many times of my Crown

>DC-300A versus AR amplifier in one only home comparison many

>years ago.

>

>A friend found that he was well rewarded with a Phase Linear

>700B amplifier with AR-LST's.

>

>Frank has expressed his opinion already and he uses Phase

>Linear 400's with his AR-LST's.

>

>The AR amp put out 60 watts RMS per channel 20 - 20,000 hz but

>was tested commonly at 100 plus watts in reviews, very

>conservative rating by AR.

>

>The amp put out about 35 watts per channel at 16 ohms 20 -

>20,000 hz but one can only guess, at the 35 ohms bass

>impedance, what the amp may have been able to put out.

>

>

Well I know for sure that I now have plenty of power for my speakers as I have traded in my Sansui for an Adcom GFA 545 rated at 100 watts rms @ 8 ohms and 150 watts rms @ 4 ohms. Now to get to the bottom of this mysterious lack of low end.

[Guest matty g]

Hi -

Did you say where the speakers were placed? Placement is one of the most important factors when it comes to bass response. Usually on the floor near a corner is the best place, though I prefer to lay them horizontaly on a shelf just above ear level.

Just as in real estate, it's Location Location Location!

Matt

[Guest leopoldstotch]

>Hi -

>

>Did you say where the speakers were placed? Placement is one

>of the most important factors when it comes to bass response.

>Usually on the floor near a corner is the best place, though I

>prefer to lay them horizontaly on a shelf just above ear

>level.

>Just as in real estate, it's Location Location Location!

>

>Matt

Hi Matt,

I have the speakers placed about two feet off the floor and about a foot away from a wall. I've tried placing them in a corner with no luck in regards to the bass. I'm going to change the caps but I'm in doubt that that will solve my problem. I may have to take these babies to someone who can take a look at them and hear what's going on. It's strange in that in the same setup my AR-2ax's sound so much lower than the AR-3's & AR-3a's and I know this shouldn't be the case.

[johnieo]

> I have the speakers placed about two feet off the floor

>and about a foot away from a wall. I've tried placing them in

>a corner with no luck in regards to the bass.

Tom Tyson may give you more complete details, but these speakers were designed as "bookcase" speakers, meaning that they best perform when radiating into a half space. I do not have that access so put them either on the floor or no more than 4 inches above the floor and about five feet apart on a long wall. One possibility is that you are loosing bass because of location. I lost bass when they were mounted 10 inches above the floor. As many have said, location and the room have a profound effects on the bass output. Also a carpet will absorb more sound than a tile floor. Many issues to consider before you decide to change components. Try them on the floor first, if you have carpet, and see if there is a significant difference between that location and your current two ft elevation.

Cheers,

[onplane]

My experience with my AR-3a's is very similar to John's and Matt's. That is, the deep bass re-enforcement comes when the 3a's are directly on the floor and very close to a wall.

My only other idea is the cap directly across the woofer. If it's value has drifted way high (and that sometimes happens with old caps), it would prevent the woofer from getting adequate current.

You could try eliminating that cap (that turns the xover into a 1st as opposed the the superior 2nd order filter), but it would be a quick test as to whether the deep bass has improved.

Hope this helps ...

Regards,

Jerry