Everyone thinks the Crate BX 100 bass amp,
with a 15" inch speaker, is 100 watts.
Well, this photo shows they are 300 watts.
So why aren't they called the Crate BX300?
Thanks for your answers,
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Crate BX100
- Thread starter king koeller
- Start date
Everyone thinks the Crate BX 100 bass amp,
with a 15" inch speaker, is 100 watts.
Well, this photo shows they are 300 watts.
So why aren't they called the Crate BX300?
Thanks for your answers,
I got the photo from a facebook marketplace ad, i went to the some on line reviews, everyone said its 100 watts, but this clearly states it's 300 watts... any one out there who has one? thanks I look forward to hearing from you.
CRATE BX-100 OWNER'S MANUAL Pdf Download | ManualsLib
Page 2 - front/rear panels
Page 3 - settings and block diagram
Page 4 - specifications
The manual states that the output power (sound) is 100 watts RMS @ 1% THD 4 ohms. Crate doesn't state what load the internal speaker is, but a Youtube video of a guy who retolexed one shows it is 4 ohms, so it's providing full power as is.
The manual says the external speaker connection is in series with the internal speaker, also shown to be in series in their block diagram. This is problematic as all amps I know of connect the external speaker in parallel. Since the internal speaker is 4 ohms, then adding an external 4 ohms speaker would be a 8 ohms load, so each speaker would get 50 watts.
They provide the working voltage (120 VAC from your wall outlet) and power consumption (300 watts) so that the user can ballpark the fuse size (I = P/V). 2.5A = 300 watts/120VAC. We add 25% for derating, so 2.5 + 25% = 3.125 A, or a 3 ampere fuse. If you bought a model for markets outside the USA you would need to do the same calculations using the voltage specific to your country, with the power consumption remaining a constant.
Page 2 - front/rear panels
Page 3 - settings and block diagram
Page 4 - specifications
The manual states that the output power (sound) is 100 watts RMS @ 1% THD 4 ohms. Crate doesn't state what load the internal speaker is, but a Youtube video of a guy who retolexed one shows it is 4 ohms, so it's providing full power as is.
The manual says the external speaker connection is in series with the internal speaker, also shown to be in series in their block diagram. This is problematic as all amps I know of connect the external speaker in parallel. Since the internal speaker is 4 ohms, then adding an external 4 ohms speaker would be a 8 ohms load, so each speaker would get 50 watts.
They provide the working voltage (120 VAC from your wall outlet) and power consumption (300 watts) so that the user can ballpark the fuse size (I = P/V). 2.5A = 300 watts/120VAC. We add 25% for derating, so 2.5 + 25% = 3.125 A, or a 3 ampere fuse. If you bought a model for markets outside the USA you would need to do the same calculations using the voltage specific to your country, with the power consumption remaining a constant.
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Yep that is maximum power consumption for the whole amplifier.
Actual RMS wattage to the speaker is 100 watts.
Normal everyday Class A/B amplifiers have efficiency in the 55 to 65 percent range.
So a typical 100 watt amp ( 65/80 watts 8 ohms) ( 90/110 watts 4 ohms)
most likely use a 250 to 280 Volt Amp or VA transformer. Hence 250 to 280 watts.
You can pull more power from a transformer but voltage sags, heat goes up.
Safety regulations typically only allow a transformer to max 120% operation.
300 watt max rating makes sense to me.
Actual RMS wattage to the speaker is 100 watts.
Normal everyday Class A/B amplifiers have efficiency in the 55 to 65 percent range.
So a typical 100 watt amp ( 65/80 watts 8 ohms) ( 90/110 watts 4 ohms)
most likely use a 250 to 280 Volt Amp or VA transformer. Hence 250 to 280 watts.
You can pull more power from a transformer but voltage sags, heat goes up.
Safety regulations typically only allow a transformer to max 120% operation.
300 watt max rating makes sense to me.
Maybe a side question here: i want to convert my BX100 to a cabinet to use with my switchable 4/8/16 ohm amp head. There are two wires going from the amp compartment to the speaker compartment and it will be easy to add jacks, but that’s assuming those wires go straight to the speaker with a 4 ohm load. But the diagram in the manual shows the external speaker jack wired “in series” to the speaker... so I’m not 100% confident about what else is wired inside the speaker compartment that I should be thinking about...
The external output jack is on the front of the amp section, so the serial connection from the speaker to the jack is internal. If you remove the head, you are left with one 4 ohms speaker and two wires. Add one jack if you don't plan to add another cabinet, otherwise get two jacks and wire them in parallel. Do not try to use the combo as a standalone speaker without disconnecting the combo's amp.
But in my opinion you're better off selling the combo and buying a bass cabinet with whatever speaker load you want. I recommend an 8 ohms cabinet so that you can add another speaker later.
But in my opinion you're better off selling the combo and buying a bass cabinet with whatever speaker load you want. I recommend an 8 ohms cabinet so that you can add another speaker later.
Thanks. Right, I was planning to just snip the wires between the amp section and speaker, they’re conveniently exposed, putting a female jack on the speaker end to connect to my tube amp head and a male plug on the end that goes to the amp so in can still sell it as a modded combo someday...
I’ve got a 2x10 8 ohm cab already, and just want to see how my tube amp sounds with this 15”... From my limited knowledge I don’t think I can use both my 8 ohm 2x10 and the 4 ohm 15” at the same time, right? My power amp is switchable 4/8/16 ohms.
What’s inside the speaker compartment? A 4 ohm speaker and a voice coil of unknown impedance that is wired to somehow equal 4 ohms total?
I’ve got a 2x10 8 ohm cab already, and just want to see how my tube amp sounds with this 15”... From my limited knowledge I don’t think I can use both my 8 ohm 2x10 and the 4 ohm 15” at the same time, right? My power amp is switchable 4/8/16 ohms.
What’s inside the speaker compartment? A 4 ohm speaker and a voice coil of unknown impedance that is wired to somehow equal 4 ohms total?
A speaker is a voice coil with a specific impedance (4 ohms in your case) attached to a speaker cone and suspended in a metal basket. The voice coil sits in a magnetic field created by a fixed magnet. That's pretty much it, no other components.
