stevie

What make is the cab?

Angling and raising a cab does work if you want to hear yourself better, but it doesn't actually do what's needed, which is improving your cab's dispersion at mid and high frequencies so that you - and your audience - can hear those vital midrange frequencies clearly. When you point your cab at your ears, you only hear those midrange frequencies when you're standing right in front of the cab, because the cab's still beaming above 1kHz or so. As soon as you step to the side, you go back the muffled sound that everyone else - the rest of your band and your audience - is hearing. The only solution is to have a cab with a decent power response. The only cabs I know of that deal with this issue properly are the Fearless 3-way designs - apart from the BCMkIII DIY design that @Chienmortbb referred to. Good quality PA cabs usually have a decent power response because their main job is reproducing midrange frequencies, although they have their own issues for bass guitar reproduction.

The crossover brings the level of the HF unit down to match the bass/mid driver and applies a high pass filter that matches the natural, upper rolloff of the bass driver. This is what virtually every bass cab manufacturer does. It's simple, it's easy and it's cheap. Both the compression driver and horn are usable down to 2.5kHz, and that's where the system could be improved. However, to get the two components to cross over at 2.5kHz, you'd need to filter the upper response of the bass driver, which means additional components. The circuit for the HF unit would also be more complex than it currently is. Chances are, you'd end up with three times as many components in the crossover, which was not the aim of the project.

The Design Diary progressed from a Beyma SM212 on its own to a Beyma SM212 with a Celestion CDX1-1445 and P.Audio PH-170 horn - all ceramic magnets. The crossover for that system disappeared from Basschat when a particular image hosting company closed down. Fortunately, chienmortbb has recently located the circuit in his files. So if anyone would like a copy - particularly @nekomatic - just ask. We then went all-neo with a Faital Pro 12 and the Celestion CDX1-1425 - again using the PH-170 horn. Using any other components would mean a complete crossover redesign. The Celestion 1415 could in theory be substituted for the 1425, as they are quite similar. However, their sensitivity is different and you'd need to account for that in the crossover. As far as inductors are concerned, there's an Ebay.uk seller who winds inductors to custom values in small quantities. The biggest European manufacturer of coils is a German company called Intertechnik, although I don't think they do custom values.

I don't doubt you in the slightest.

Man cannot live by in ears alone, grasshopper. 😁

If I were looking for a cab for slapping, I'd look very closely at the tweeter being used. Some makers - not very many - fit good quality tweeters to their cabs but most fit a generic cheapo Foster of P.Audio phenolic diagram bullet tweeter, which is awful and one of the reasons so many bass players turn them off. Sad to say, no bass cab manufacturer fits a genuinely high quality HF unit. If you want one of those, you need to be looking at a PA cab.

When I lived in the north west, Salford was the place to avoid like the plague. Unless things have changed since the arrival of the BBC, that area probably accounts for the city's number one position.

You mean if he'd made a racist comment it would have been a racist comment. Too true. You seem to have missed the 'joke' bit. 😄

It will certainly be easier to hear yourself with the GR than what you currently have. So you may have found your solution. It'll be interesting to hear what you think anyway.

With a 10" Jensen and a bullet tweeter in the box, it's unlikely to be uncoloured either. A little puzzling indeed.

I can almost predict the way this thread will go. I've been on Basschat too long. 😀

I have samples of both the Pulse 10 and the B10N-300X drivers. The Pulse has a bigger bottom end than the BN10 in this box but isn't quite as loud. Top end extension is about the same. Although there's a difference of 100W in the thermal power handling, the excursion capability (xmax) is fairly similar. So they should start to complain at about the same time.

With these kinds of comparisons, it really is necessary to compare like with like. It's not clear whether both amps were set flat but they should be. Was a DI being used or the matching cab? This can complicate matters because you are then comparing two different components at the same time. Interesting though.

Interesting. I'll give it a go after a quick listen. The Tonehammer has no lows and no highs. It's all mids and they're not very pleasant. The GR has more lows and a smoother sound, but the top end is lacking. I'd personally be much happier with the GR. The drums sound great but are too loud for this exercise. Nice one @johnpaulbass! We could do with more of these.

With 2 Faital Pro 10s and a Faital Pro 15 in the box, it's perfectly possible that the thermal power handling is 900W (rms). That's already quite impressive - so why bump it up to 1,100W or 2,200W? And the 300W peak power handling tweeter is just nonsense. Thermal power handling is irrelevant here anyway, as system output will be limited by driver excursion or port air velocity - more likely the latter - well before the thermal rating is reached. You can't compare power handling figures unless you know how they've been calculated. Most manufacturers very sensibly base their specs on the power ratings supplied by the driver manufacturers, in which case you'd hope to see RMS or AES standard next to them. If this information is missing, you could well be looking at a figure that is up to twice the actual one.

Interesting to know that which cab is better was actually irrelevant to your choice, Al. What mattered was which cab is lighter. We could have solved that one for you three years ago.

Tilting a cab (or raising it up) doesn't improve a cab's dispersion; it just allows the mid and high frequencies to be beamed in the direction of your ears. It's a fudge because, if you step to the side, those high frequencies disappear. When a cab has good dispersion, the sound remains the same no matter where you're listening from. For the audience too. A good PA cab can do it, but bass cabs usually fail. Which is why they're often tilted or raised.

Although there doesn't seem much point in fitting a tweeter and then switching it off (unless I'm missing something). Bear in mind that, despite its relatively low cost, this is a good quality HF unit and a class above what you find in most bass cabs. As far as I can tell, most players who switch tweeters off do so because they sound bad. This compression driver/horn combination sounds really nice

Very nice work, John. Don't discount the possibility of adding a tweeter later. It's definitely worth it even if your repertoire doesn't include slap. 😊

Sounds like a plan. What size of ports will fit on the baffle?

I reckon you have about 30 litres net. The tuning appears to be in the region of 80Hz, which is OK for a vocal cab or a guitar cab, but not good for bass. To make matters worse, as Downunderwonder correctly points out, the rear entrance to the ports is constrained. It looks like the designer didn't know what he was doing. If you block one of the ports and open up the rear of the remaining port, you'll have a fighting chance. That will probably tune the cab to around 60Hz. It's difficult to be accurate here because the proximity of the ports to the rear baffle affects the tuning. You might like to get hold of a Celestion 12BN-300S, which is claimed by many to be close to the EV you sold. No guarantees though.