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Which speaker with a 1/4W tube amp?

Rotus623

Member
2010-09-20 4:34 am
I picked up a Blackheart Killer Ant a few days back and plugged it into my 4x12 celestion cab. This thing kicks man!! Although it defeats my purpose, plugging it into a half stack. It is a .25W all tube amplifier that has that natural overdrive at a bedroom volume. The cab that "goes" with it is a Blackheart BH110, and has an Eminence 1016B speaker in it. I can't find any info on this speaker. Does anyone have any ideas on which 12" speaker would give me the best open cab classic overdriven rock tone? I have a 1x12" open back cab I want to use. Keep in mind that the wattage must be reletivaly low, probably around 35W or less. Any ideas??
 

45

Member
2008-12-18 2:29 am
UK
I picked up a Blackheart Killer Ant a few days back and plugged it into my 4x12 celestion cab. This thing kicks man!! Although it defeats my purpose, plugging it into a half stack. It is a .25W all tube amplifier that has that natural overdrive at a bedroom volume. The cab that "goes" with it is a Blackheart BH110, and has an Eminence 1016B speaker in it. I can't find any info on this speaker. Does anyone have any ideas on which 12" speaker would give me the best open cab classic overdriven rock tone? I have a 1x12" open back cab I want to use. Keep in mind that the wattage must be reletivaly low, probably around 35W or less. Any ideas??

The wattage of the driver is just a misleading electrical rating. Nothing to do with the sound, the amplifier etc.
The moving mass could make a big difference. If this is too heavy maybe your amp will sound dull. It's a bit like the lag of the oldfashioned turbo-charged engines.....
I would try the Eminence GB128 which is also very efficient at 101+ dB/1W.
The tone you get also depends very much on the Zout of your amp. If this is too low you could have a darker sound. A 10" cone has a bit more trebles by default, usually.
In my experience the Eminence Legend 1058 (or 10516 if you want 16 ohms) is a better choice for most low power single ended amps.

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Rotus623

Member
2010-09-20 4:34 am
Thanks! Those celestions are rather expensive. I actually just ordered a 10516 Eminence Legend (that 45 suggested). They are only $50 and the description seems to match exactly what I am looking for. I'll let you guys know how it turns out when I get it installed. Thanks again.
 

kevinkr

Administrator
Paid Member
Thanks! Those celestions are rather expensive. I actually just ordered a 10516 Eminence Legend (that 45 suggested). They are only $50 and the description seems to match exactly what I am looking for. I'll let you guys know how it turns out when I get it installed. Thanks again.

Yeah, they are very expensive - I'd probably not choose one myself for such a project, but I have heard the classic and it sounded pretty nice with a 1/2W PP amplifier.

Hopefully the Eminence will fit the bill nicely.
 

Rotus623

Member
2010-09-20 4:34 am
Update: I installed the speaker (Eminence Legend 10516) in an open back cabinet. This speaker creates the EXACT sound that I was looking for. It has a great bluesy/classic rock sound. With the volume/gain turned all the way up it sounds like Jimi Hendrix purple haze, mid-way up it sounds like Lynard Skynard gimme three steps. Great advice 45, thanks a lot. For $50.00 this speaker is pure genius!!
 

45

Member
2008-12-18 2:29 am
UK
Update: I installed the speaker (Eminence Legend 10516) in an open back cabinet. This speaker creates the EXACT sound that I was looking for. It has a great bluesy/classic rock sound. With the volume/gain turned all the way up it sounds like Jimi Hendrix purple haze, mid-way up it sounds like Lynard Skynard gimme three steps. Great advice 45, thanks a lot. For $50.00 this speaker is pure genius!!

I am pleased you found it.

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Rotus623

Member
2010-09-20 4:34 am
Yeah, as soon as I can get my vidoes on here I am going to do a demo of the Killer Ant with open back speaker cab with 12ax7's and then with a 12at7 in the power amp. This thing really is KILLER. Crushing tube overdrive at bedrooms levels. It's nice to be able to get down without having tinnitus for a few hours afterwards......
 

scetoaux

Member
2010-10-30 8:11 pm
I have a 1/2 watt tube guitar amp that I built. I have a Weber 25 watt Greenback clone that sounds great! The best thing about Weber, they will break in the speaker before they ship it to you. This really does make a difference. If you have to break in a 25 watt speaker with a sub 1 watt amp, it will take a long time.

Also, if you want a bit of extra low end punch, they will make the speaker with a heavier magnet if you ask them to. Also, their prices are great.
 

45

Member
2008-12-18 2:29 am
UK
Well, I guess the differences in the plate resistance of the 12at7 and 12ax7 have proven a problem. The at7 blew today. Guess Im goin to try a 5751 there instead. : )

The plate resistance may affect the sound but has nothing to do with reliability.
Possibly the 'AT7 is just more delicate when overdriven.
You could also try with a 12BZ7 which has got the same gain factor of a 12AX7 but has half of plate resistance and double mutual conductance.
You can only find NOS 12BZ7's but they are rather cheap....

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45

Member
2008-12-18 2:29 am
UK
Cool, thanks. I think I want to lower the gain a lil'. I'll let you know how the 5751's sound.

Fine.
Just in case, the 12BZ7 will need 2X heater current in comparison to a 12AX7.
Check out the power transformer to see if it runs too hot or the filament voltage is too much lower than 6.3V (or 12.6V depending on how filaments are wired up).
5.7V should still be fine.

45