Neo driver issues.

[alexclaber]

You might also be getting a very small amount of thermal flux loss,
Neos are not as thermally flux stable as some other magnet types.

Loss of flux is irreversible. To lose magnet strength you would have to take your drivers well beyond thermal failure. Or wait for many many decades to pass.

Alex

 

[BassmanPaul]

That's what it is then! Neos go into a time warp between sets and come back having aged twenty or so years each time!

Paul

 

[Bassmec]

That's what it is then! Neos go into a time warp between sets and come back having aged twenty or so years each time!

Paul

Flux capacitors apart:
Temperature Characteristics
If the Neodymium and Samarium Cobalt materials are required to operate at temperatures other than ambient, consideration must be given to the effect on the magnet's performance. Normally operating below 200C causes no adverse effects, and in fact performance increases with decreasing temperatures. The Neodymium materials do exhibit a temporary, or reversible loss of flux with increasing temperatures. The severity of these losses and the possiblity of permanent, or irreversible losses must be considered when the design is being developed. The grade of material, temperature extremes, magnet geometry, and circuit configuration will all influence the ability of a given device to withstand adverse thermal conditions without experiencing unexpected losses. Please consult the individual product data sheets for specific temperature data, or consult our application engineering department for additional information.

 

[Petebass]

Normally operating below 200C causes no adverse effects,

Your Honour, the defence rests! If you could generate that sort of heat through a speaker during a gig, which BTW you can't, the glue would let go loooong before the neo demagnetises.

Poor Neo's, they get blamed for everything.

 

[Gab124]

Like I said before,we don't play loud,definitely not enough to wear plugs,and we defintely don't turn up as the night goes on.The singer sometimes goes into the audience and finds some poor guy to sing to,and if one of us is too loud,she'll tell us the first chance she gets! So,we keep the stage volume in check.That's why I "think" I'm not pushing the amp too hard.Might be.I am going to try a different setup next gig and see what happens.Got an Ashly BP-41 I've been wanting to try out anyway,so good time to do it. I don't doubt your statements, it's that this is the first time I've run into this,so I'm try to put together the possible reasons. I do appreciate everyones input! I got as lot more response than I expected.

If you are running volume a 12 in a band context then you are loud enough to cause both ear fatigue and eventual damage IMO. This could get worse with time. IME I also have a TFB550 and sometimes notice this (i do and have to wear plugs all the time now though) and I have found that if i turn down the bass eq some it does not push the amp so hard and I do not get that effect. I also started running two 8 ohm cabs and never notice it anymore. Oh yes, I also have neo's
.02cents

 

[alexclaber]

Like I said before,we don't play loud,definitely not enough to wear plugs...

If you have a drummer then you are loud enough to need earplugs.

Alex

 

[Petebass]

If you have a drummer then you are loud enough to need earplugs.

Alex

+ 1000. And I've taken measurements with SPL meters to prove it. I won't go into it now for threat of derailing the thread, but it's worth mentioning for the purposes of pointing out that there's enough "loudness" present to make ear fatigue etc a factor in this case.

 

[73jbass]

If you are running volume a 12 in a band context then you are loud enough to cause both ear fatigue and eventual damage IMO. This could get worse with time. IME I also have a TFB550 and sometimes notice this (i do and have to wear plugs all the time now though) and I have found that if i turn down the bass eq some it does not push the amp so hard and I do not get that effect. I also started running two 8 ohm cabs and never notice it anymore. Oh yes, I also have neo's
.02cents

My typical settings for my amp are: gain 3 to 4 ( about 10 oclock),all 4 bands of eq flat,timbre 10 to 11 oclock,enhance 12 oclock,and master at 5 (12 oclock). So I'm not using any extreme settings.I used this setup with two 8 ohm cabs recently,and got the same results.And,like I said before,we keep our stage volume down.We let the PA do the work.I don't have to compete with a loud drummer or guitar player.The guitarist playes a 15 watt tube head. Hardly deafening.I'm going to try a different rig and see what that does.

 

[warnergt]

I'm not a speaker expert but I am an electrical engineer and I've
witnessed what you describe in high power car stereo equipment.
I suspect it is the speaker voice coils warming up and increasing
in resistance. It's a well known fact that the speaker coil resistance
goes up with temperature -- and the higher resistances cause even
more heat so the problem compounds itself.

By the way, I'm not trying to start any conspiracy theories or anything
but I suspect this phenomenon may also be directly related to the perception
that some high-end, expensive speaker cables perform better than
their less expensive counterparts. The listener evaluates a system
with the cheap cables (and hot speakers). As the listener changes
to the expensive cables, the speakers are cooling down. So, when
he resumes using the speakers with the expensive cables, the
sound is now different and often better.

Since neo magnets are always smaller than their ferrite counterparts,
it may be that these neo magnets structures have more difficulty
dissipating the heat. This could make neo speakers more susceptible
to heat problems. I don't know; I can only speculate.

 

[Petebass]

Since neo magnets are always smaller than their ferrite counterparts,
it may be that these neo magnets structures have more difficulty
dissipating the heat. This could make neo speakers more susceptible
to heat problems. I don't know; I can only speculate.

Nah, modern speakers, neo and ferrite, have cooling mechanisms built into them. They use the movement of the speaker cone to funnel moving air through the parts of the speaker than need cooling. Most vent that air out through a hole in the back of the speaker. The vent hole is clearly visible if you pull the speaker out and have a look at the back. Other speakers vent through the dust cap, meaning of course the dust cab material has to allow for this, but this is less common in pro audio drivers.

 

[KJung]

Your Honour, the defence rests! If you could generate that sort of heat through a speaker during a gig, which BTW you can't, the glue would let go loooong before the neo demagnetises.

Poor Neo's, they get blamed for everything.

+1 I think Bassmec stopped reading about this stuff in 1970

 

[chadds]

My typical settings for my amp are: gain 3 to 4 ( about 10 oclock),all 4 bands of eq flat,timbre 10 to 11 oclock,enhance 12 oclock,and master at 5 (12 oclock). So I'm not using any extreme settings.I used this setup with two 8 ohm cabs recently,and got the same results.And,like I said before,we keep our stage volume down.We let the PA do the work.I don't have to compete with a loud drummer or guitar player.The guitarist playes a 15 watt tube head. Hardly deafening.I'm going to try a different rig and see what that does.

Not disagreeing here but my guitarists use 15w Brunos, Hayseeds, and Fuchs and they can drown out a whole band. Some distortion, flapping, limiting, honkiness etc. can occur at really reasonable levels if your gain is wrong, your pickups are hot or too close to the strings, you don't have enough watts to take the transients smoothly, or your girlfriend's mother is in the audience.

 

[Rick Auricchio]

The human ear is hundreds of times more sensitive in the upper mids. That's why the guitar was invented centuries ago, because it could be heard acoustically!

 

[B-string]

Gee maybe that's why a double bass is so much larger than a guitar? But size of anything connected with bass means nothing right?

 

[Rick Auricchio]

Gee maybe that's why a double bass is so much larger than a guitar?)

It has to be that large to resonate acoustically. Just as saxophones have different sizes, so each resonates at its appropriate frequencies.

 

[Sten]

If you typically use only one cab, I would highly recommend getting a reasonably high SPL 4ohm cab like the /---/, the Epi310UL, /---/

Sorry for digging up an oldish thread, but I was reading this and wanted to point out that Epi 310 UL is 5.3 Ohm and there is a more recent thread where a user also finds that this may be a reason why it does not sound loud enough with his amp (LM2 IIRC).

 

[KJung]

Sorry for digging up an oldish thread, but I was reading this and wanted to point out that Epi 310 UL is 5.3 Ohm and there is a more recent thread where a user also finds that this may be a reason why it does not sound loud enough with his amp (LM2 IIRC).

+1 that it is 5.3ohms. The user in that other thread, IMO, is mistaken for attributing his volume issue to the slightly higher than 4ohm impedance IMO and IME.

 

[billfitzmaurice]

+1 that it is 5.3ohms. The user in that other thread, IMO, is mistaken for attributing his volume issue to the slightly higher than 4ohm impedance IMO and IME.

+1. The difference in output between a 4 ohm and a 5.3 ohm cab would be barely measurable, and totally inaudible.