Celestion speaker replacement question.

[honeyiscool]

Really a guitar amp question, but... I figure guitar forum people are useless at caring at this level anyway. So in my recent love for all things Class D, I've converted to Class D on guitar as well, and bought a Quilter MicroPro 12 HD, which is basically a 100W amp connected to a closed back 12" with a Celestion BN12-300S bass driver in it. I really liked it.

Then I bought a MicroPro 10" to kind of complement it, which normally has a guitar speaker. Didn't like the sound. So I bought a Celestion TN1020 pressed steel neodymium bass/midrange driver on a whim and stuck it in that combo. I think I struck gold or something because this sounds really good! In fact, it is sounding better than the 12" speaker for me.

So what do I do now? Going back and forth, it seems like the TN1020 sounds bigger, more balanced, less boxy, than the BN12-300S loaded box, which, until I tried the TN1020, sounded completely fine but now sounds strident and boxy. Both cabinets are exactly the same size (yeah, I know, but it's a guitar amp), and I've measured the internal dimensions: 15 7/8" wide, 12 3/4" tall, 5 1/8" deep. It's a completely sealed cabinet.

Celestion TN1020: TN1020

Celestion BN12-300S: [Invalid or Expired Link Removed]

I think it's too cramped in there for a baffle converter (front loaded cabinet) so my only options are to ditch the 12" combo, have it modified, or find another 12" speaker (preferably neodymium). Is it possible for me to try to get what I'm getting from one 10" speaker in a 12" speaker without trying a million drivers out?

ORRRR... do I just live with the 12"? I mean, it was perfectly usable before, gigged with it plenty. It didn't just become crap overnight.

(Lastly, do you think it's safe to play keyboards or the occasional bass through this amp when loaded with these speakers?)

Thanks.

 

[BadExample]

Celestion BN12-300S: [Invalid or Expired Link Removed]

IMO This one does not look like a good candidate for a sealed box, but not sure if that matters for geetar. Maybe try it open back?

 

[honeyiscool]

IMO This one does not look like a good candidate for a sealed box, but not sure if that matters for geetar. Maybe try it open back?

It's a combo, so unfortunately I'm stuck with what I have.

What are the implications of using a speaker that's not ideal for a sealed box in a sealed box?

What are the implications of using a speaker in a sealed box that is smaller than the ideal sealed volume? The cabinet comes out to exactly 0.6 ft^3 (or 17 liters) and I can't imagine that's a recommended size for any midrange or bass driver.

 

[BadExample]

I might be wrong on the first question, but I think both questions get the same answer: Not as deep of bass, but tighter bass.

Ideal sealed cab size is in the eye of the beholder.

 

[honeyiscool]

I might be wrong on the first question, but I think both questions get the same answer: Not as deep of bass, but tighter bass.

Ideal sealed cab size is in the eye of the beholder.

Thanks! I mean, for guitar, both go deep enough, certainly as deep sounding as a standard Marshall 4x12" loaded with G12M drivers when I A/B'd against the combo.

Do you think they would safely handle some light playing of bass or keyboard without speaker damage? There's a second channel for line/mic signals which sounds very clean and loud.

 

[BassmanPaul]

IMO This one does not look like a good candidate for a sealed box, but not sure if that matters for geetar. Maybe try it open back Jack?

FIFY

 

[Bassbeater]

If you record guitar a lot, it might be good to keep both options and keep experimenting. You can buy a broken combo amp for guitar and mount a new speaker with an input.
You can get away with murder on guitar cab designs, so you might as well keep it interesting IMO. You can also get away with good sound trying some really cheap spec'd and mis-used speakers in guitar cabs. If it sounds good it is good. As you well know, you need to be cautious with volume levels on hooligan cabs, esp with bass.
As for speaker damage, my experience when it happens is that in a sealed cab you typically fry the coil with too much wattage, in an open back you typically rip the material with too much bass.

 

[honeyiscool]

If you record guitar a lot, it might be good to keep both options and keep experimenting. You can buy a broken combo amp for guitar and mount a new speaker with an input.
You can get away with murder on guitar cab designs, so you might as well keep it interesting IMO. You can also get away with good sound trying some really cheap spec'd and mis-used speakers in guitar cabs. If it sounds good it is good. As you well know, you need to be cautious with volume levels on hooligan cabs, esp with bass.
As for speaker damage, my experience when it happens is that in a sealed cab you typically fry the coil with too much wattage, in an open back you typically rip the material with too much bass.

I do record guitar a lot, but this is more of a gigging amp. I tend to record with low wattage tube amps and over the last year, I've had a lot of luck using a Suhr Reactive Load box for silent recording and using speaker emulations.

For gigging, since these amps have so much wattage (100W per channel), I'm finding that a basic clean and neutral response from the built-in speaker will handle just about anything. I'm not relying on the speaker for breakup or tonal character the way I would with a tube amp. Plus, these Quilters have XLR output, so I can more or less use them the same way I would use a bass amp, just to cover my area and to let the PA do the rest of the work.

I will probably get an open back cabinet speaker cabinet so I have some place to try out some other speakers with more dimension and character, since a small closed back isn't the most 3D sound in the world.

 

[BadExample]

FIFY

Yer mer'erin' the king's Engrish!

 

[Bassbeater]

Although I sometimes record clean guitar sounds through a sealed cabinet and an open cab with mics and mix with DI, I much prefer the open back cabs for distortion and higher volume with a band. Basically everything that makes a bass cab terrible makes a guitar cab amazing. FWIW I find it hard to emulate breakup well, I get better results pushing a smaller guitar cab and amp in the near upper limits. Lots of ways to get there though.

 

[honeyiscool]

Although I sometimes record clean guitar sounds through a sealed cabinet and an open cab with mics and mix with DI, I much prefer the open back cabs for distortion and higher volume with a band. Basically everything that makes a bass cab terrible makes a guitar cab amazing. FWIW I find it hard to emulate breakup well, I get better results pushing a smaller guitar cab and amp in the near upper limits. Lots of ways to get there though.

"Lots of ways to get there though."

I'm finding that last sentence to be so true. For many years, I thought, I liked open cabs and so forth, they sound really great for everything, and then at gig volume, I'd find myself lost for clarity and just be throwing a bunch of sounds into the air and I just took it for granted that I would lose out in volume wars because I wasn't willing to go above certain numbers.

With a small, sealed cabinet, I find that I get a very dry sound with a very forceful lower midrange. It's almost jarring how clear it sounds when you're in the room on your own. Then you add drums, bass, another guitar, horns, organ, etc. Last thing I need at that point is ambience. In a stage mix, that dry sound is the reason I can still hear all the nuances of my tone without turning up. And with a speaker that doesn't introduce its own distortion or character, no surprises happen at a higher volume.

It's certainly true that early guitar amp designs are poor choices for bass. I mean, bass amps and guitar amps started out basically the same. But bass amps got better, and guitar amps basically stuck to the 1960s because they were already kind of good enough. Lately, though, having walked the path of the last few decades of guitar amp development in a matter of a couple of years, I'm finding that you can embrace newer technologies even for guitar and still get familiar sounding results. I mean, that shouldn't surprise bassists because bass amps have improved in so many ways since the 1960s, yet you can still get a vintage tone through the latest gear. I'm just finding out, I guess, that guitar isn't so special, either.

 

[BassmanPaul]

Do you really think that a 100W amp is powerful? I wonder what you’d think of my 2KW capable power amp!

 

[BadExample]

With a small, sealed cabinet, I find that I get a very dry sound with a very forceful lower midrange.

That would be the tightening up and the joy of a sealed cab. Clear and tight lows.

On the sealed one that sounds boxy, Have you tried stuffing some poly-fill in it? Get a bag at the sewing shop for about $10, try half full and full full. It will sound better... or worse. It won't sound the same.

 

[BadExample]

Do you really think that a 100W amp is powerful? I wonder what you’d think of my 2KW capable power amp!

I know you have at least 3500 Watts total in MI amps. I'm trying to catch up lately.

For bass:
1600 + 900 + 600 = 3100
For geetar:
300 + 100 + 65 + 35 = 500

3600 Watts total. No stereo amps allowed except power amps used as bass amps!

Have I caught up yet

I have a feeling you have a few more amps I don't know about

 

[honeyiscool]

Do you really think that a 100W amp is powerful? I wonder what you’d think of my 2KW capable power amp!

For guitar, 100W offers a pretty stupid amount of power.

That would be the tightening up and the joy of a sealed cab. Clear and tight lows.

On the sealed one that sounds boxy, Have you tried stuffing some poly-fill in it? Get a bag at the sewing shop for about $10, try half full and full full. It will sound better... or worse. It won't sound the same.

Do you just line the cab a little bit with it? How does one get it to stick to the walls?

 

[BogeyBass]

.6 is little small for 12"

Id assume it has big bass peak or blooms at certain frequencies
Maybe blurry mids.

If box isnt stuffed just buy sheet of poly stuffing for quilt blankets and shoove it in there. Box is so small friction of material could hold it in. Or little spray glue. Staples can be used but make sure they sink well. Cause if they fall out they get attracted. into the speaker magnet/ spider. So use very very minimal staples.

Likewise there is some drivers more friendly to smaller spaces. Usually drivers designed for small floor monitors. Might be eminence driver. Ill take a look. Think there is a neo for floor monitors With alot of highend

Even low watt open back guitar speakers that are ok for sealed are really really boomy in small box.

.9 is somewhat ok for 10" and few could work ok in .6 but its really pushing it.

1.3 is about as small as id go for a 12" sealed and that would be rather boomy for most 12".

Point is eminence designed the neo
Deltalite II 2512 to go in a sealed box as small as .9 which is pretty dang small for a 12" its somewhat of a likely canidate for .6

Using software models would confirm the ripple response of the current driver and be used as a comparison to any new likely canidates. Modeling would show how bloomy or boomy it would be. Realistic highend response is more found with manufacture data sheets

 

[honeyiscool]

.6 is little small for 12"

Id assume it has big bass peak or blooms at certain frequencies
Maybe blurry mids.

If box isnt stuffed just buy sheet of poly stuffing for quilt blankets and shoove it in there. Box is so small friction of material could hold it in. Or little spray glue. Staples can be used but make sure they sink well. Cause if they fall out they get attracted. into the speaker magnet/ spider. So use very very minimal staples.

Likewise there is some drivers more friendly to smaller spaces. Usually drivers designed for small floor monitors. Might be eminence driver. Ill take a look. Think there is a neo for floor monitors With alot of highend

Even low watt open back guitar speakers that are ok for sealed are really really boomy in small box.

.9 is somewhat ok for 10" and few could work ok in .6 but its really pushing it.

1.3 is about as small as id go for a 12" sealed and that would be rather boomy for most 12".

Point is eminence designed the neo
Deltalite II 2512 to go in a sealed box as small as .9 which is pretty dang small for a 12" its somewhat of a likely canidate for .6

Using software models would confirm the ripple response of the current driver and be used as a comparison to any new likely canidates. Modeling would show how bloomy or boomy it would be. Realistic highend response is more found with manufacture data sheets

Am I missing something? I'm plugging in parameters for the Celestion BN12-300S into the DIY Audio & Video Speaker Box Enclosure Designer/Calculator with published specifications and clicking "Compute Sealed Box" and for dimensions, I'm getting this:

This is what I get for the TN1020, the 10" that I like so much:

This is what I get for the TN1225, the 12" from the same range that I have somewhat considered:

What's with these tiny Vb numbers? Are Celestion bass and midrange drivers THAT different from industry standard?

 

[BadExample]

Am I missing something? I'm plugging in parameters for the BN12-300S into the DIY Audio & Video Speaker Box Enclosure Designer/Calculator with published specifications and clicking "Compute Sealed Box" and for dimensions, I'm getting this:

View attachment 2968065

For free software for MI speakers try winISD pro for Windows or @fdeck 's on-line program for any OS.

 

[BogeyBass]

The program is calculating to a default .707 Qtc

.707 is considered to be the flatest response

And as you can tell the speaker you like so much does well in a small enclosure

And likewise you can increase the ripple response a little higher and shoot for .8 Qtc to get a smaller box.

Win isd will plot the response so you can visually see how the enclosure will effect the response and likewise calculate .707 Qtc and you can raise Qtc or basically make box smaller.

In this case were not trying to build a enclosure.
We are trying to see how driver behaves in the preset volume of .6 cubic feet

For most part drivers you are curious about if they show relatively small .707 Qtc volume they most likely wont be so boomy and blurry in your enclosure.

 

[BogeyBass]

What's with these tiny Vb numbers? Are Celestion bass and midrange drivers THAT different from industry standard?

That specific 10" driver you choose and like the most is a more midrange type driver. The resonant frequency is little high at 80 hz
Its designed to be more upper midrange driver so its ideal ripple response is gonna be in a smaller enclosure. .6 to .8 cubic feet is fairly typical. Which of course works well with your enclosure.

Most 10" for deeper bass would have resonant frequency around 55 to 65 hz and probably have pretty large enclosure to get a .707 Qtc. Be more like 1.3 cubic feet to even 1.9 for some.

the 12" you modeled
They have lower resonant frequencies maybe around 46 to 52hz
As well and designed for lower bandwith or more bass specific.
So likely to be looking for larger airspace like they did.

12" your thinking of seems to want a even larger space than the factory driver. So probably be more boomy.

Im not familar with celestion line.
Im sure they might have a 12" more suited for small enclosures. Maybe not so bass specific more like a moniter speaker or pa midbass.
Maybe have slightly higher Fs or resonant frequency. Like 58 to 70hz