Beyma 10G40

[cdrbass]

Hi Talkbassists,

I'm looking at purchasing the Beyma 10g40 400RMS bass speaker for my set-up. I'm looking to use it as the speaker in a 1x10 cabinet, with a 300w RMS head. It's hard to find opinions from musicians on this speaker. The frequency response is supposed to be 45hz - 4.0Khz, so I'm wondering, is 4.0Khz high enough for the overtones on my upright bass to speak well?

All opinions welcome. Thanks!

[Mike Arnopol]

It's my favorite stand-alone 10 incher for electric and upright. The 12" is great also.

[Mike Arnopol]

I prefer slightly boosting the high end for electric with a speaker like this. I find myself turning down the little horn tweeters on most 2 way cabs. I hate horn tweeters. (at least the pro-sound variety) Now if they used a dome tweeter---that's another story. I've designed and built a lot of cabs for myself and others. I've used most of the high-end US and European drivers and find this specific Beyma series my favorite.

[cdrbass]

Thanks, Mike. I am intending to drop into an existing Ampeg 1x10 cabinet that I have. The Ampeg speaker (Aura Sound) really seems average to me. Wish me luck!

[fdeck]

My advice is that driver replacement is basically a speaker design project, except that the box has already been chosen for you. But you can use the speaker design tools such as WinISD to decide whether a particular driver in a particular box makes sense, or to compare a whole bunch of off the shelf drivers.

[Mike Arnopol]

Is the box you're using ported or a sealed box? As Francis stated, the speaker/cabinet issue is really important. One issue that I'm not in agreement with a lot of the speaker design software is that the design parameters are based on flat response. While this is critical to stereo speakers, for our needs the ability to eq really changes things. I've used various design software in the past and found that my favorite designs were at odds with the software reccomendations. I've designed for impact, response and tone as opposed to optimum flat response. I start wih the theoretical, but ultimately let my ear be the guide.
The reason I mention whether the cabinet is sealed or ported is that a speaker (like the Beyma) which is designed for a ported enclosure will not sound good in a sealed boxIt is possible to add a port though, at which point the design software would be helpful. I build my cabs with an adjustable port, which is a feature I really dig.

[cdrbass]

Wow guys, thanks for the constructive input. I don't know if I'm getting over my head at this point or not. Here's another question. Can a port in a cabinet be one hole? I'm curious whether or not I can remove my tweeter (which I find useless) and have the hole act as a port for a new speaker.

I'm sure I'm way beyond my comprehension at this point.

Thanks again,

[Eric Hochberg]

Originally Posted by Mike Arnopol

I build my cabs with an adjustable port, which is a feature I really dig.

So Mike, as long as we're on the subject, what 15" driver would you recommend for my old box? The EV I've always used is bugging me, I think it only goes up to 3kHZ and is super old school sounding.

Sorry for the hijack...

[cdrbass]

Mike, I forgot to mention that it is a sealed cabinet. Although you may have figured that much out by now.

[Mike Arnopol]

You can remove the tweeter and use that hole, b ut you will need a PVC or cardboard tube of say, 1 1/2 or 2" diameter. What I have done on my cabs is mount it in a slightly larger piece of plywood ( say 3" by 3") I then use a gasket and T-nuts to mount it over the hole that is big enough for the tube to pass through. This way you can experiment with different port lengths to find the best sound and response. If you just use the hole without he tube the enclosure would be tuned to too high of a frequency. With tuned-port cabs, anything below the tuning of the cab (determined by port length and diameter) would leave the speaker unloaded, meaning that the speaker sees any frequency under the tuning as free air. Which means that if he tuning of the cab is say, 60 hz, that the speaker would be behaving as if in free air on any frequencies under 60 hz. ( which means flopping around as if not in a cabinet) You'd be surprised how many bass cabs are tuned too high. (SWR, for instance) I typically tune my cabs low, so that a speaker would still be loaded for a B string. And before guys like Francis or amp manufacturers have come out with subsonic filters the subsonics from piezo pickups would play havoc with speakers. So with my cabs, the bass would have to be boosted a bit more, but because of the tuning the speaker would always be loaded. (which is why I would strongly reccomend one of Francis' high pass filters) It's all personal taste, soundwise as far as cab design. My point is that in the real world with access to eq there are many more practical aspects of cabinet and tuning design than frequency response and impedance curves.
Eric--I would recommend ANYTHING over an EV. My least favorite speaker. I would recommend a Beyma 15G40 or try to find a JBL K140. The K series is my favorite JBL by a long shot. Any of these 15's are going to have limited high frequency response. The Beyma is listed as 1500 hz, but I think that the high end of any 15 is going to be similar to the EV. Give me a call. I have a basement of blown 15's that you could have reconed. I have a few Gauss, an RCF which is very nice---but I just realized that I have a blown Altec 421a which is an awesome bass guitar speaker. A little lower power handling, but really nice bloom and timbre.

[fdeck]

Originally Posted by ehochberg

So Mike, as long as we're on the subject, what 15" driver would you recommend for my old box? The EV I've always used is bugging me, I think it only goes up to 3kHZ and is super old school sounding.

Sorry for the hijack...

I wonder how the "non-LF" Eminence 3015 would behave there. Another option might be to modify the front baffle to accept a 12 and a 6" mid. Since many 15's are reportedly built too small, the box might be just right for a 12. And the port tuning is uncorrelated to the driver diameter. The "Fearful" design discussed over on the BG side includes a 12/6 version.

Originally Posted by Mike Arnopol

Is the box you're using ported or a sealed box? As Francis stated, the speaker/cabinet issue is really important. One issue that I'm not in agreement with a lot of the speaker design software is that the design parameters are based on flat response. While this is critical to stereo speakers, for our needs the ability to eq really changes things. I've used various design software in the past and found that my favorite designs were at odds with the software reccomendations. I've designed for impact, response and tone as opposed to optimum flat response.

That's been my experience too. In fact I don't even bother with the step of letting the software recommend anything. My "program" doesn't offer that feature. To help me get the ball rolling, I started with a combination of educated guesses about successful commercial bass cabs, and the measured response of my GK Micro Bass combo.

[Mike Arnopol]

Hey Francis
It's funny, but I've experimented with many cabinet sizes and configurations. I've found that I prefer cabinets that are technically "undersized". Yes, the larger cabinets go lower without eq and may be more efficient, but the bigger cabinets were not as "focused" for my taste. I have a nice woodshop and have tried many, many cabinet ideas.
One thing for sound "production" (what we're trying to do) as opposed to reproduction (stereos) is that any passive coil that the low end driver goes through SERIOUSLY degrades the sound. I don't like passive crossovers. Damping factor is really compromised. Biamping is another thing. If I had my way in a perfect world, I would always biamp. I used to do it all the time. I also had a stupidly big and complicated rig. For me, geting your low frequency cab on the floor crossed over at say 120 hz and having your upper bass little cab elevated. Now you can get into 8" and 6 1/2" midrange drivers that go to 6 or 8 khz---perfect setup for me. The Audax prosound 6 1/2 drivers are awesome. But only biamped. I talked to the EA people about building a biamped amp and they kind of laughed at me. They were right of course in that I'd probably be the only guy on the planet using it. No cabinet is perfect, but the reason I use EA is that they are the most intelligent compromise. Some of my cabs sound better, but weigh as much as a Fender Twin. The EA cabs are really well engineered. Are they perfect? No way---but for me the best compromise. Their CXL12 goes louder than any 12 I've ever used. Ea cabs are all tipped up in the midrange with the CXL and Wizzy 10's being the worst culprits. But, use the eq and voila!. With SWR or Eden or Hartke cabs or Aguilar I can EQ until I'm blue in the face and still not get a functional sound. because the basic note production and envelope are wrong for me. Even with small rigs I'd biamp. You have a Wizzy 10 on the floor and a 4" or 6" driver on a chair crossed over at 160 hz and its the perfect combination of focused, deep bass and pristine mids and highs. I have to open up my M-Line and see how they folded their transmission line because for it's size it has to be a compromise. I've built very elaborite transmission lines for hi fi and it's always been my favorite sounding bass. Much better than sealed box or reflex.

[Eric Hochberg]

Originally Posted by fdeck

I wonder how the "non-LF" Eminence 3015 would behave there. Another option might be to modify the front baffle to accept a 12 and a 6" mid. Since many 15's are reportedly built too small, the box might be just right for a 12. And the port tuning is uncorrelated to the driver diameter. The "Fearful" design discussed over on the BG side includes a 12/6 version.

Thanks, the reason I asked Mike is that he built the cab I'm talking about for me 25 years ago. It's still going strong but probably don't want to do any major mods at this point.

Mike - Thanks, I'll give you a call.

[fdeck]

Originally Posted by ehochberg

Thanks, the reason I asked Mike is that he built the cab I'm talking about for me 25 years ago. It's still going strong but probably don't want to do any major mods at this point.

Mike - Thanks, I'll give you a call.

Aha, a conspiracy.

[fdeck]

Originally Posted by Mike Arnopol

Hey Francis
It's funny, but I've experimented with many cabinet sizes and configurations. I've found that I prefer cabinets that are technically "undersized". Yes, the larger cabinets go lower without eq and may be more efficient, but the bigger cabinets were not as "focused" for my taste. I have a nice woodshop and have tried many, many cabinet ideas.

That's been my experience too. At my little web page, I have an article that attempts to shed some light on the design of "undersized" boxes, written mainly to provide an alternative to widespread "optimal" design methods.

I remember way back when, as a teenager, I discovered a book on speaker design in the library, and ordered an EVM-15B from Musicians Friend. The book did not even give an alternative to an "optimal" design, and I didn't understand the physics well enough to know any better, so I ended up with a huge box that sounded horrible. In desperation, I took that driver and stuffed it into a smaller sealed box made from the scrap from the first project, and gave away the first box to a friend. From this, and various urban folklore, I fell into the "sealed speakers are better" mentality for many years until I finally learned how to work my way through the equations and my eyes were opened.

At least, my sealed box and a Peavey head got me through college. A big amp is OK when it is on wheels and never leaves the music building. Then while in grad school, I caught the downsize bug spontaneously one night while hauling my big speaker and head through a gravel parking lot in the rain, in ankle-deep "wintery mix" in South Bend.

[Mike Arnopol]

I think that reflex cabs are the worst of the available designs. The only positive point with reflex is increased efficiency. In my opinion what comes out of a port is essentially synthesized bass which increases the quantity of bass, but it's bad quality bass. Sealed boxes and transmission lines are wayyy better in terms of quality of bass in the lowest 2 octaves. Problem is that the prosound drivers that have high power handling are engineered for reflex cabs. They have too much overall damping (QTS) The EV speakers have very high damping (low QTS) High damping means more control but less "bloom". Too little damping (high QTS) means less control. The Beyma is about .30 which is perfect for a reflex cab for my taste. To sound good in a sealed box I prefer a QTS of .40 to .50. Since the sealed box has its own damping (the sealed box air cavity provides control) to have enough bloom and impact. If you wonder how those little GK 12" amps sound reasonably good look at the speakers. The foam surround offers very little damping. That's how thay can use such a small box. Transmission lines are unique. To me, they offer the best bass. The rear radiation from the speaker goes through a long labyrinth and is slowed down and absorbed by the time it passes through its "port" To me, the bass has the perfect amount of control.

[Mike Arnopol]

Also, by tuning the cabinets low (say 25 hz) the port doesn't even function in the musical range, really. Efficiency is lower and the bass has to be boosted a bit, but the high power low QTS speaker is essentially seeing a sealed box within the musical range. This has evolved as my preferred design. Most "speaker" designers would disagree, but I'm a bass player first, and I know that the functionality on a gig is a parameter that apparently eludes most designers.

[cdrbass]

How can I know whether or not a speaker is for a sealed or ported cabinet?

[Mike Arnopol]

by he QTS. It's a spec you can find. For ported, QTS of .30 or below. (keeping in mind what I mentioned earlier that a very low QTS of say, .21 may be TOO tight sounding) For sealed box, .40 or above, keeping in mind that a very high QTS of say .60 might have too small of a magnet with too little control. I've used speakers with a QTS of .35 in a sealed box with good results, too.