Would two 8 ohm 2x10's have the same frequency range as one 4 ohm 4x10?

[rcarraher]

Lets say two 8 ohm 2x10's each have a frequency range of 40Hz-40KHz. Lets say one 4 ohm 4x10 has a frequency range of 30Hz-40KHz. If I paired the two 2x10's together, would they cover the same frequency ground as the single 4x10?

In other words would two 8 ohm 2x10's paired together gain low end frequency response and sound more like a 4x10?

I play a 5 string bass so I prefer to have nice low end definition and I'm not sure if two 2x10's would give me enough low end. I like the portability of the 2x10's but if my sound would suffer, I'd rather have one 4x10.

I made up those frequency ranges, but I think they are close to the cabinets I am looking at.

Thanks for the help.

As a rule of thumb (not always true because there are things you can do, electronically to compensate) when talking freq response, less resistance means higher freq response. This is why single coil pickups "usually" have better highs where humbuckers emphasize the mids and lows.

Now this isn't writ in stone, like I said and is only really true in RC LC Filter circuits and even then can be compensated for with EQ circuitry etc...but as an engineer, first thing I think when we lower the resistances. Better highs. But read the spec on the cab in question.

 

[Ric5]

I play through 2 2x10 cabs both 8 ohms. It is just like playing through a 4 ohm 4x10 cabinet. except it is easier to move.

 

[grifff]

I play through 2 2x10 cabs both 8 ohms. It is just like playing through a 4 ohm 4x10 cabinet. except it is easier to move.

Have you tried playing a 5 string through it?

Thanks for the excellent responses everyone, I've learned things that I never thought I would. Keep em coming.

 

[billfitzmaurice]

As a rule of thumb (not always true because there are things you can do, electronically to compensate) when talking freq response, less resistance means higher freq response. This is why single coil pickups "usually" have better highs where humbuckers emphasize the mids and lows.

Now this isn't writ in stone, like I said and is only really true in RC LC Filter circuits and even then can be compensated for with EQ circuitry etc...but as an engineer, first thing I think when we lower the resistances. Better highs. But read the spec on the cab in question.

Where highs are concerned resistance has no bearing. Impedance does, but only peripherally. What does matter is the inductance of the voice coil, and lower is better for highs. But if the drivers used are identical so will be the inductance of each driver, so it's a non-issue where the OP is concerned.

BTW, buckers have poor highs due to phase cancellation caused by the distance between the two out of phase coils vis a vis the string length. Stacked buckers eliminate that problem, that's why they have better highs than side by side coil buckers.

 

[David Jayne]

..., less resistance means higher freq response. This is why single coil pickups "usually" have better highs where humbuckers emphasize the mids and lows.

No, that's not why.

BTW, buckers have poor highs due to phase cancellation caused by the distance between the two out of phase coils vis a vis the string length.

THAT'S why.

 

[Mat_F]

I disagree.

Porting pushes the box size/efficiency/bass extension tradeoff into more favorable territory than you can get with a sealed box.

It's quite possible to design a vented box to mimic the frequency response of a sealed box; I've done it many times.

A ported box gives the designer (and sometimes the end user) useful options for optimizing the system for a given application.

Finally, woofers whose parameters are conducive to good midrange performance usually work better in a vented box than in a sealed box. These tend to be expensive woofers, not cheap ones.

Which type of box is best depends on the specific application, in my opinion.

But mimicking is hardly ever a good thing. The only benefit of a ported design is that it cuts the manufacturing costs, but this is far out-weighed by the negative aspects that come with it. Actually achieving the desired frequency response without cheating or cutting corners will always give better results. Obviously this comes at a price, but (like everything) you get what you pay for.

 

[bhubb3rd]

Interesting topic and appropriately timed! I just acquired a second Berg AE210 and used both of them for the first time last night. I have been using a Berg AE410, but the weight got the better of me. I stacked them vertically and had some interesting observations. First, I sure did hear a lot of string noise! I think that's primarily because the speakers were finally at the level (stacked vertically) that I could actually hear the highs. I also noticed the low end was boomy and would even feedback at times. The sound was much more uneven than I thought it was, quite a bit of variation between strings. Again, probably because I could actually hear it at ear level! Maybe it's time to test a compressor. The AE210 is rear ported, the AE410 is front, don't know if that made a difference. The cabs were about 6 to 8' away from the back wall. The acoustics kinda suck at this venue, they stick us in a cubby hole like room. I was also using my new MoMark 800 and for some reason, just couldn't dial in a sound I was happy with. Grabbed my MB LM Tube 800, problem solved! So, I guess I need to work with all this new stuff to get a sound I like, but would say the 410 may have a slight advantage to the (2) 210's, but not enough to make me haul the 410 around anymore. I am going to subscribe!

 

[Mat_F]

For sure on that. Better do a search on the guy you're trying to lecture about speakers. What's next, giving golf tips to Tiger Woods?

I already looked at his website and I’m not trying to lecture anyone at all. I am simply stating facts that have been demonstrated to me by 2 major speaker manufacturers that are very well known worldwide. I certainly wouldn’t be disagreeing with the owner of a speaker manufacturing company unless I knew for sure that the information I had was correct and proven.

Everyone has the right to make their own decision on this and I’m not trying to force my opinions on anyone. My only intention was to put across the point that increasing the drive unit size by 2” will give a much bigger increase in frequency depth than doubling or even tripling the cabinet volume. Most people generally don’t get the chance to realise this, as larger drive units normally come in bigger cabinets anyway. But anyone who is able to compare the differences properly and without any biased views or motives, will appreciate that the results are clear and undeniable.

 

[rcarraher]

Where highs are concerned resistance has no bearing. Impedance does, but only peripherally. What does matter is the inductance of the voice coil, and lower is better for highs. But if the drivers used are identical so will be the inductance of each driver, so it's a non-issue where the OP is concerned.

BTW, buckers have poor highs due to phase cancellation caused by the distance between the two out of phase coils vis a vis the string length. Stacked buckers eliminate that problem, that's why they have better highs than side by side coil buckers.

Impedance is only resistance in an AC circuit. Both measured in ohms. Parts of the reason, and a good part, that buckers have poor highs is the total length of the wire in the windings. Longer wire, more resistance. Also, more windings, the higher the back current when power is applied. This back current is what sets up the "resistance". The bucker does phase cancel, thus giving a hum canceling effect. Thats what they are designed for, but you still loose high freq response. Stacked buckers do have the effect of giving you back some of the highs, but not to the extent of "breaking them pickup into two seperate single coils.

 

[billfitzmaurice]

The cabs were about 6 to 8' away from the back wall.

The worst possible placement. Depending on the exact distance from the cone to the wall and back again you'll get up to a 24dB deep suckout in the bass in the vicinity of 40-50 Hz, which kills the deep bass and makes booming more noticeable. OTOH placement half to a third that distance from the wall would raise the suckout frequency and help control that boom.

The bucker does phase cancel, thus giving a hum canceling effect. Thats what they are designed for, but you still loose high freq response. Stacked buckers do have the effect of giving you back some of the highs, but not to the extent of "breaking them pickup into two seperate single coils.

Humbuckers work by having the two coils wired reverse polarity, so that noise received by both coils cancels out. That would also cancel out the signal from the strings except the magnets in the two coils are also reverse polarity with respect to each other. The magnetically sourced signal from the strings is therefore out of phase magnetically in the two coils, but as they're electrically out of phase as well the final result is in phase. But the frequencies near where the distance between the two lines of magnets are 1/2 wavelength apart suffer phase cancellation. If that distance is 1 inch, for instance, the frequencies cancelled are centered around 2260 Hz. With stacked buckers the lower coil is too far away from the strings for this effect to occur.

I am simply stating facts that have been demonstrated to me by 2 major speaker manufacturers that are very well known worldwide. I certainly wouldn’t be disagreeing with the owner of a speaker manufacturing company unless I knew for sure that the information I had was correct and proven.

Facts aren't facts unless they're backed up with documentation. IMO your statements indicate that you don't understand how speakers actually work. That's not intended to be an insult, not every bassplayer is an acoustical engineer to say the least, nor should they be expected to be.

 

[Mat_F]

Facts aren't facts unless they're backed up with documentation. IMO your statements indicate that you don't understand how speakers actually work. That's not intended to be an insult, not every bassplayer is an acoustical engineer to say the least, nor should they be expected to be.

You are entitled to your opinion, but I don't see you or anyone else producing any documentation. Besides which, I would never believe the contents of a document produced by someone I don’t know and would never expect anyone else to either. The only way to know something for sure is to prove it for yourself or for it to be proven to you by someone you know and trust. You don't need to be an acoustical engineer to test and compare the equipment I mentioned previously. You only need to understand how to test and compare them accurately.

I only wanted to share the knowledge I have gained through personal experience on this subject. Everything I have learned has been tried, tested and cross-referenced in order to come to an accurate conclusion. With that being backed up by 2 major speaker manufacturers (that have both been making speakers since the 1960’s) as well as comparisons made to equipment produced by a further 8 speaker manufacturers, I will not blindly believe the claims of someone I don’t know, especially when this contradicts everything I know to be fact.

I have no reason to make false claims or waste other people’s time by misleading them, I have far better things to do with my life. As I have said just about all there is to say, I will leave it for everyone to make their own mind up.

 

[grifff]

...Grabbed my MB LM Tube 800, problem solved! So, I guess I need to work with all this new stuff to get a sound I like, but would say the 410 may have a slight advantage to the (2) 210's, but not enough to make me haul the 410 around anymore. I am going to subscribe!

Not to go too far off topic but how do you like your Markbass LMTube800? I'm about to place an order for one.

 

[hbarcat]

The information I stated is correct. The only thing I didn't mention is that I was talking about sealed box designs. Ported designs would make more of a difference, but ports are just a way to try and cover up the limitations of cheap drive units that aren't capable of producing the desired frequencies at adequate volumes. Closed box designs (when done well) are far superior and I personally would never use anything else.

I wasn't going to comment on this but your last post stating that your opinion in this regard is a fact while the very well researched facts that contradict your post are opinions is something I want to correct.

There are other people reading this thread who are being presented with the spurious claim that "ports are just a way to try and cover up the limitations of cheap drive units that aren't capable of producing the desired frequencies at adequate volumes. Closed box designs (when done well) are far superior . . . " and they should be aware that this is just not the case.

There are a great many situations where the frequency response of a ported cabinet design is inherently superior to a sealed cabinet design in every way that matters to the user of the cabinet. Of course, there are also situations where a sealed design may be more desirable to the user and that's what is so involved in the field of acoustic science and in the craft of speaker cabinet design - knowing what design is the most appropriate for what situation and knowing how to tweak the details to get the most out of that design.

For my own gigging equipment and the use I put it to, a sealed cabinet design is inherently inferior to the ported cabs that I currently have. I've come to that conclusion through quite a few years of research, trial and error and asking a lot of questions of a lot of very knowledgeable people who have been giving me answers because they want to help me, not because they want to sell me something. My speakers in my cabs give me exactly the sound I want and they do that in a practical package. I just plain can't get what I want from a sealed cab.

 

[bhubb3rd]

As far as my LMT800, I love it! Hard to see how you could go wrong and since the only place you can get one is the Musicians Friend group, buy it and try it for 45 days. You can always send it back!

 

[bhubb3rd]

Question for Bill - In situations where I have to use my rear ported 210's on a stage or venue where I can't get within a foot or so from the back wall of the stage, what options do I have to counteract the booming you described earlier. I never considered this when I purchased the 210's, perhaps I should have, since I play in crazy venues and many times don't have anything behind me. Guess I should just go ahead and build my BFM Jacks! Thanks, Bill for your insight here.

 

[DukeLeJeune]

But mimicking is hardly ever a good thing.

A well-designed vented cab can outperform a good sealed cab in a number of areas that are important for a bass player.

The only benefit of a ported design is that it cuts the manufacturing costs, but this is far out-weighed by the negative aspects that come with it.

While both of these statements are incorrect, it's quite possible that both are consistent with what your experience has been.

I would never believe the contents of a document produced by someone I don’t know.

That's a rather limiting attitude... but on the other hand you just saved me a lot of typing.

 

[ehque]

Vented cabs are cheaper than sealed cabs? Come on!

Perhaps your experience with larger drivers going lower has to do with all those OTHER parameters which are changed when going from a smaller one to a larger one - parameters which are independent of cone size.

 

[JimmyM]

Originally Posted by Mat_F
I would never believe the contents of a document produced by someone I don’t know.

That's a rather limiting attitude... but on the other hand you just saved me a lot of typing.

Dang, dude! That one went into the bone!!! That wasn't a comedy jab...that was a comedy punch to the temple! You rock, sir.

 

[Mat_F]

I've come to that conclusion through quite a few years of research, trial and error and asking a lot of questions of a lot of very knowledgeable people who have been giving me answers because they want to help me, not because they want to sell me something.

Same here.

 

[alexclaber]

If you compare an 8", a 10" and a 12" drive unit (manufactured using the same materials) in a cabinet with a volume of 3800 square inches, the 8" will go down to around 35Hz, the 10" to around 27Hz and the 12" to around 20Hz.

If you take three bass guitar woofers with identical Fs, Qts and Mms/Sd but differing nominal diameters, and place them in the same cabinets the smaller woofers will go lower whilst the larger woofers will go louder (due to the lower Vas of the smaller woofers causing Fb (in a sealed box) or the higher frequency resonant peak (in a ported box) to be shifted less far upwards in frequency).

The only benefit of a ported design is that it cuts the manufacturing costs, but this is far out-weighed by the negative aspects that come with it.

Anyone stating this has clearly failed to consider excursion limited power handling and low frequency sensitivity, and is thus making a statement that is not relevant to bass guitar or pro sound cabs.

Alex