40+60w 16Ω speakers in a 212 cab= sounds bad

[deci belle]

I've been using a single d130 in a 115 tone-ring cab. It sounds ok if you like the JBLs.

I just had a blonde bassman style sealed + separated 212 cab made and loaded it with a 60w 16Ω speaker (from a Crate V15) and a 40w 16Ω tonetubby. I figured the two different wattages would kind of even out and work ok together. They are wired in parallel.

I'm using the 212 cab with a tweed deluxe and also a head powered by 5e8a power and output transformers. The tweed deluxe sounds fine with the cab. The 5e8a powered 6g6b and 5f6a channels sound fine at lower frequencies, but the speakers in the 212 cab crap out (warbly oscillating tones) when I play higher single notes.

The d130 handles the same head/guitar signal (playing Brian Setzer stuff) without this problem.

I tightened all the screws in the cab. It is very robust (RA Woods cab).

Is it possible that the speakers are being overpowered somehow? The head is about 35w (two 5u4gb + two Russian 6L6str) and the speakers are a 60w and 40w in parallel.

[J M Fahey]

Probably nothing bad, but you can't compare standard generic Guitar speakers with a JBL; even less to an old one.

[pdf64]

'(warbly oscillating tones)'
That's often a symptom of an underfiltered powered supply - ripple on the B+ modules the signal.
Maybe the sealed 2x12 cab is putting out frequencies that your other cabs are rolling off?
Pete

[deci belle]

Yes, Pete. I'm not sure what all is happening, yet. I have the standard filter arrangement on the amp ('66 Showman), new-ish 80µFs in series for the main and 30µF on the screens. It's only sounding rough and warbly on the smallest strings.

I still think it's the speaker(s), but I'll try a different guitar today.

I planned to get a pair of V30s for this 212 anyway, but don't like the idea of throwing money at a problem without knowing why first.

The cab is definitely putting out frequencies the others aren't!! The low-end sounds gorgeous~ maybe burlier speakers are in order…

[pdf64]

Only 40uF of reservoir cap, on a 4 x 6L6GC amp?
I suspect that your speakers are fine, they are just reproducing the low end better than your other cabs; rather the warble issue is very probably due to ripple on the B+.
I'd look to upgrade the reservoir caps to 220uF; the rectifier diodes should be able to cope but as they've been in service for 47 years, it may be prudent to replace them.
Pete

[deci belle]

Ya, only 40µF, Pete. Showmans only came with 35µF. It has two 6L6s now and the two NOS Sylvania 5u4gb tubes have only been in the amp since I put the 35w Tweed Twin iron and caps in less than two years ago.

It's not making that sound today. Maybe the 40w speaker got too hot after playing hard for hours? I thought the speakers would kind of average-out their ratings, but maybe not?

I wish someone would chime in about that.

Thank you for the suggestions about the possible cause(s) of this problem, Pete!

[potatofarmer]

It's my understanding that they'll share the current equally but your power handling will only be roughly double the lower-rated speaker. So, you know, if you were to pump 100W into the cab, the 60W would be fine (for a moment) but the 40W would probably go poof, followed by the 60W. I haven't blown up a speaker yet (knock on, er, MDF) but I can only assume glitter flies out, like a magic trick.

Have you tried each speaker separately to see if you can isolate it?

[Enzo]

The speakers are the same impedance, so they share power equally. Power RATING is irrelevant to that, they still SHARE equally.

That means if you apply 80 watts, they each see 40 watts and are both OK. If you apply 120 watts, they each will see 60 watts. The 60 watt speaker will be happy with it, and the 40 watt speaker will not. They don;t "average out" in any way. Your cabinet is good for 80 watts, period. The fact that one speaker is able to withstand more doesn't change what the lesser power one can do.

[deci belle]

Yow! I'm glad that didn't happen yet, Paul! Enzo, that's great information— just what I needed to hear! I never turned the volume up past "6", so I know I wasn't cranking the full power of the amp into the speakers.

I couldn't make it sound bad yesterday, even though I played it just as hard and long, but since I lowered the pickups away from the strings yesterday, maybe the pickups being too close to the treble strings was causing or contributing to either one or both speakers not liking being subject to that much of a strident signal from the p'ups at the higher frequencies.

I hope that was the problem!

[J M Fahey]

I never turned the volume up past "6", so I know I wasn't cranking the full power of the amp into the speakers.

Don't be so sure

Most Guitar amps have some extra gain on tap to cope with weak pickups/strings/players, so on a classic Fender amp, "6" is already the onset of clipping which by definition is max. power; and on Marshalls, notably Plexies and such, 1.5 or 2 is already distortion, again max power.

Never trust the volume knob "number".

[Jazz P Bass]

And some Fender amps are maxed out on '3'.

[deci belle]

haha!! Well I did know I was maxxed out just enough for the Setzer tone!!

I'll report if it happens again.

[deci belle]

Figured it out …212 cab aimed a big ass fan oh the humanity

[Leo_Gnardo]

Figured it out …212 cab aimed a big ass fan oh the humanity

Join the club - I've done that! Hm why does this sound better with the fan off? Unwanted "Leslie" sort of effect, sorta makes every mid-hi pitch note gargle.

[J M Fahey]

Join the club - I've done that! Hm why does this sound better with the fan off? Unwanted "Leslie" sort of effect, sorta makes every mid-hi pitch note gargle.

True, cool effect .... unless you don't want it, of course.

My kids had fits of laughter speaking and screaming into a fan blade, 10 inches away from it.

Found it *incredibly* funny.

Dad agreed, of course

FWIW Leslie effect might have been discovered that way