Sensitivity of Ampeg SVT210av

[Old Ozzie Guy]

Hi all, I can't seem to get any specs regarding Sensitivity of said Ampeg 2x10. I'm hoping the other side of plannet may have more info.. (IV tried the Ampeg site but can only find " sales propaganda", I'm guessing lack of No.s pointing to V inefficient.

Thanks all 

[itu]

That is something companies do not advertise frequently. Exact specs are not so popular among marketing people - my guess is that you are not able to find it anywhere. Wattage on the other hand...

[yorks5stringer]

I've heard they have quite thick skin....

[Lozz196]

2 hours ago, yorks5stringer said:

I've heard they have quite thick skin....

Yep, you can criticise their curtains and they don’t even blink an eyelid 

[Bill Fitzmaurice]

Since it's loaded with Eminence OEM probably built on the Alpha 10 chassis 95dB is a reasonable expectation. So is a high Fs and short xmax.

[Sparky Mark]

It's shown in this table from the Ampeg quick start document. It doesn't mean it will be as good at producing bass as a 610 cab of similar sensitivity. Don't fixate on sensitivity; it's only part of a cabinet's performance. 

[msb]

I’ve been using one at home , fairly quiet practice levels , and occasional rehearsal (louder). It’s not a bother to lug around.

Good cab , but not a great one.

[itu]

On 12/03/2023 at 15:45, Sparky Mark said:

It's shown in this table from the Ampeg quick start document.

With this data it is easy to calculate theoretical max dBs.

[Bill Fitzmaurice]

Without xmax you can't calculate maximum SPL.

[Downunderwonder]

1 hour ago, Bill Fitzmaurice said:

Without xmax you can't calculate maximum SPL.

Believing the claimed power handling from the table you get the "theoretical" max SPL very easily, is what Itu was getting at.

[Bill Fitzmaurice]

Probably, but thermal power capacity has no relationship with maximum SPL. A 100w driver with 5mm xmax will go 3dB louder than a 200w driver with 3.5mm xmax.

[Downunderwonder]

I guess we are really talking about whether or not Ampeg is telling us useless information in their table. It is not unreasonable to use their RMS number and sensitivity to derive SPL but it could be we are being lead to telling ourselves a lie.

 

It used to be said that Ampeg were better than most with their RMS power handling numbers well related to actual bass guitar signals.

[Bill Fitzmaurice]

No doubt Ampeg is one of the more honest manufacturers. Their power ratings are conservative. But the fact remains that without xmax or Vd one simply cannot calculate max SPL. Try it yourself, using any of the common loudspeaker design programs, leaving xmax/Vd out of the parameters. You can calculate response, impedance, phase, group delay, port velocity, but when you go to the max SPL chart it's left blank for the lack of the required specs.

 

This isn't picking on Ampeg by any means. AFAIK Barefaced is the only manufacturer that provides that critical bit of information.

[Downunderwonder]

If we accept that Ampeg are selling us a bass cab and not a mid cab then I don't think it's wrong to infer SPL from sensitivity and power handling by assuming the xmax is available.

 

When the assumption fails we get the accusation of spec fudging.

[xgsjx]

5 hours ago, Bill Fitzmaurice said:

This isn't picking on Ampeg by any means. AFAIK Barefaced is the only manufacturer that provides that critical bit of information.

10 or so years ago MarkBass used to give the xmax, but don’t anymore. 

[Bill Fitzmaurice]

8 hours ago, Downunderwonder said:

If we accept that Ampeg are selling us a bass cab and not a mid cab then I don't think it's wrong to infer SPL from sensitivity and power handling by assuming the xmax is available.

In most cases the xmax isn't available. The mechanical power limit of drivers averages around half the thermal limit. Some are higher, some are less. Some even have a mechanical capacity equal to or greater than the thermal. But those are high cost premium drivers that are seldom seen in electric bass cabs. Here again don't take my word for it, verify it yourself with speaker modeling software. As a for instance, the Eminence Deltalite II 2510 is the most popular neo ten inch platform. The thermal rating is 250w. The mechanical limit in the critical 80-100Hz region is 100w. And the 2510 is better than most. The most popular ceramic ten platform is the Eminence Beta 10. The thermal limit is 250w. The mechanical limit is 60w. 

[stevie]

Bill's post highlights the dangers of choosing a cab based on the manufacturer's specs. Sensitivity and maximum SPL are certainly  not as simple as some people think. I note that nobody has mentioned power compression. Even if you have xmax and you understand the different ways of quoting it, without a figure for power compression, you can't calculate maximum SPL.

 

 

[Old Ozzie Guy]

And also the type/tonal specifics of sound source or guitar thru a 50 watt Marshall hd 1 X 25 watt "greenback"

Extreme example!!

[Bill Fitzmaurice]

A good example. Xmax of the Greenback, and for that matter most guitar drivers, is very short. The result is high distortion at moderate power levels. This relates to us in the form of the original 1969 SVT. It was loaded with short xmax musical instrument drivers, as there were no long xmax tens in 1969. Even eight of them couldn't run clean with the 300w SVT head. The cabs were rated at 240w thermal, while the mechanical capacity was at best 120w. That's why those who could afford them used the Ampeg recommended two cabs.