stevie

You can certainly use the Monza with your Elf, @Stub Mandrel, but you're not going to get the most out of it unless you have a more powerful amp.

This doesn't mean that it's low sensitivity, but it will handle lots of power without complaining and go as loud as most players on this forum will ever need - on its own.

I'm currently prototyping a cab that Stub has more or less written the specification for in his post. It makes the most of the tiny heads like the Elf that are popular at the moment. It's still a couple of months away yet but, if anyone's curious, I can provide the spec and pricing via pm.

Thanks, @RichardH - let's do that.

You'll find the drawings you need on page 6, @Stub Mandrel. It's worth skimming through the thread and in particular following the link to @Phil Starr's cabinet assembly video.

22 hours ago, Bill Fitzmaurice said:

Thermal power ratings are worthless, as are driver sizes. The only way to know how cabs compare on paper is with SPL charts and driver excursion specs, which are written with invisible ink, stored away in the deep recesses of Churchill's bunker, guarded by Agents of Shield. 🤥

Since the K212 is local go try it, along side the 210. Then you'll know for sure.

No SPL charts, but Eminence's TS parameters for these drivers are listed in a thread about this particular cabinet at the 'other place'. 

Re 14.62 Ohms

fs 58.7 Hz
Le 1.06 mH

Mms 21.5 grams
QM 2.76

Mmd 17.7 grams
QE 0.81

Cms 0.341 mm/N
QT 0.62

Rms 2.877 N*sec/m
Xmax 3.30 mm

Vas 61.2 liters
Pmax 75 Watts

SD 355.4 cm^2
Bl 12.01 Tm

VD 117.4 cm^3
Coil Diameter 1.50 Inches

EBP 72.9
Gap Height 0.24 Inches

Magnet Weight 20 ounces
Efficiency 1.49 %

Winding Width 0.500 inches
SPL 93.7 dB 1W-1m

So does the mod consist of adding a resistor to the board - and a switch if you want it switchable? Does it boost the mids or just bring the frequency response back to flat?

I wouldn't miss this for the world. It's a brilliant day out. I'll be bringing some LFSys cabs for people to try out - probably also some new ones that I'm currently working on.

My current gigging gear is a Squier Classic Vibe Precision and a Veyron head. So they'll probably be coming as well.

Following with interest.

The horns have a nominal 90 x 60 degree dispersion. The idea of using them vertically is to send more of the high frequency information to the player's ears.  I've AB'd the two options and you can definitely hear the difference, as the low crossover frequency means that quite a lot of the sound of the bass comes through the horn. The orientation of the horn doesn't affect the sound in the far field (i.e., the audience).

The idea behind all of this is to allow players to easily hear what they're playing. Even when you stack two cabs the way @GlamBass74 has done, a vertically aligned horn makes a difference to audibility - so if it were my rig, I'd rotate the top horn and leave the bottom one - best of both worlds. 😊

Nice job, Jon.

You're both right. 😄 I posted the graph for a highpassed cab. Here's the one I meant to post, which Eminence have modelled with 400 watts. It's comfortable with that power from 45Hz up. Tune the box a bit lower and it will just about make 600 watts at 40Hz (but would certainly benefit from highpassing at that frequency). It's also worth bearing in mind that bass guitar isn't the same at test tones.

Bill's right to point out that many (most) bass cabs cannot make use of their thermal power rating because they exceed xmax well before that point. However, I think he's being a bit pessimistic about the xmax limits of premium drivers.  Eminence publish info on the displacement capability of the KL3010LF, which shows that xmax remains below the driver's rated power of 450 watts from 40Hz up. If it could handle the power, it could take 600W before reaching the xmax limit.

Not the whole story, of course.

(By the way, the displacement graph is a bit odd because the curve should continue to rise below 40Hz.)

After a brief visit back home to be checked out, the Monaco demo cab is out and about again. It's currently on its way to Manchester. So if any players in the north west fancy a blast, please get in touch and I'll arrange it.

Here is a pair of cabs in the back of a Honda Jazz (on top of a pile of shopping bags).

Here are a couple of quick pics. The more glamorous ones will take a bit longer.

Phil plugged the BC110T in and we had a quick listen during our auditions. In view of the cost of the self-build cab, It held up surprisingly well. It was clear and well balanced but you could easily hear the effect of the higher quality components used in the Monza, which took everything to the next level. Considering the 110T took me an hour to design, and the Monza several months, I'd jolly well hope so, too.☺️

I'm on it.....

I'm not sure what Bill's problem was with Celestion but they've provided TS parameters for their bass and PA drivers for as long as I can remember. They don't usually publish a full set of parameters for their guitar drivers, however, as there's not much point. But they are available.

Marshall used this speaker in a 2x15" reflex bass cab, the 1551, but I don't expect it went very loud.

I think ChatGTP mined Talkbass for that info.

It's a mixture of factual information and complete tosh (well written tosh, mind you). You'll only know the difference if you have some knowledge of the subject. But then why would you ask ChatGTP?

You're welcome, @fretmeister☺️

1 hour ago, Bill Fitzmaurice said:

Frequency gaps aren't the issue. Uniformity of off-axis response is. The higher you go with the woofer the narrower the dispersion angle, eventually resulting in full out beaming. Most bass cabs cross over to the tweeter in the 3.5kHz to 4kHz range, which is where even a ten will beam. Crossing over at 2kHz to 2.5kHz is much better. Doing so without worry of blowing the tweeter requires a high order crossover, preferably with a 24dB/octave high pass. No manufacturer I'm aware of does so. Barefaced might, but their literature doesn't say.

Another Plus 1.

Ahermmm..... https://www.lfsys.co.uk/bassguitarproducts

"Driver compliment is a cast-chassis Faital Pro 12" driver crossed over at 2kHz to a Celestion compression driver on a vertically aligned, cast aluminium CD horn. This arrangment generates a dispersion pattern that enables players to hear every detail of their sound even when standing right next to the cabinet."

Off-axis response is critical in sound reinforcement, which is why high-end PA speaker manufacturers pay a lot of attention to it.

This video explains it really well, albeit from a hi-fi perspective. It does get a bit techical though:

It must have been good if you're thinking about next year already.☺️

This is my second trade with Mike - this time I sold him an amp. Mike is very easy to deal with and I can recommend him to anyone wishing to buy or sell. Thanks again, MIke.

Thanks for the interest, @tubbybloke68. @Phil Starr's right - I'm fitting out the first couple of production models as we speak. The design is a more compact version of the Monaco, using the same CD horn/neo compression driver combo and the 10" equivalent of the bass driver. Genuine 600W AES (max. 1200W) thermal power handling. Like the Monaco, the low end has been tailored to go deep while preventing boom even at high SPLs. Full two-way crossover at 2kHz with HF protection. Weighs just under 11kg and kicks like a mule.

I'll announce availability on here as soon as I have sorted the photography. Any questions, please ask.

There's some debate on the forums as to whether the later versions are actually 400W drivers. However, they have a 2.5" coil and even with today's technology a 2.5" coil is normally limited to 300W.

What's the volume? You can test the cab's tuning frequency using the rice-on-the-cone method and a downloadable frequency generator. I did post a link but the forum didn't like it. Do a Google search for loudspeaker rice grain test. Here's an online tone generator: https://www.szynalski.com/tone-generator/