Phil Starr

I'm thinking room acoustics rather than your bass was the problem, that and unfamiliarity with the gear. It's surprising how much processing our brains do which we are unaware of. Playing our own gear with our own bands we don't need to hear much to know what is going on, jamming with strangers in an open mic, well you just need more to work with. You said the sound out front was good for the other bassist, chances were it was OK out there for you too. There just isn't time or opportunity at this sort of thing to get out front or even to move around much, you were probably jammed into a corner right on top of the cab with it pointing at your knees, possibly with a low ceiling just to compound things. The trouble is there are enough mids but they aren't coming your way. If you re eq and adjust your volumes then all you will do is make the mix right where you are but wrong for everyone else. Get someone else whose ears you trust out in the audience to tell you if it sounds ok. If possible try tilting the cab back to point at you or try to move further away from the cab to capture more of what the audience are hearing.

There is nothing different in many ways between a PA bass driver and the driver in a dedicated bass cab, they are governed by the same laws of physics. In a sense they both have to do the same job, reproduce the sound of the deepest instruments in the band, usually the bass. At the moment technology has reached the stage where a single 12 can produce enough power to enable the bass to match an unamplified drum kit, two can do this fairly easily. A 15" speaker with it's extra surface area will be slightly more efficient all other things being equal and will need slightly less excursion to achieve the same sound level. In practice all things are rarely equal and it's the implementation of the design that makes one speaker 'better' than another. The thing is to use your judgement, have a listen to the speakers just as you would audition a dedicated bass cab. if they were perfect all FRFR speakers would sound identical and clearly they don't. If you regularly struggle with a single 12" bass cab then you are going to struggle with a single 12" PA cab, and in all probability your band are too loud on stage. I've given a thorough audition to those RCF's and at the moment they beat the Yamahas hands down on the midrange transparency at least to my ears, but the proof of he speaker is in the listening.

If they are the same ohms then they will share the power equally. That means the total handling is twice the handling of the lowest wattage cab, in this case 250W so 500W in total.

Lovely

Are you talking a drum kit here? If not then the Yamaha Stagepas 300 might be suitable. The mixer is stored in the back of the speakers and you don't have to move it out of there if you don't want. Cheap used because the newer Stagepas 400 is louder. I use one or two Behringer 1320D monitors plus a little Alto mixer for just this purpose but you'd probably find this a little too bulky.

If you are successfully using a 112 then any quality 12" PA speaker will probably work for you. If you are playing decent wedding gigs then really you shouldn't be cutting corners with your gear. Go for RCF, QSC or top range Yamaha and you are likely to get something that will handle the bass you need and prove reliable. If you can afford it then it's always a good idea to think about using the same speakers as monitors that you use for PA. That means if something goes down mid gig you can do a straight swap and just go on playing in most cases.

There's limitations if you go this route. Have a look at the specs, this is the 12" version https://www.altoproaudio.com/downloads/Alto-Professional-TS212-Spec-Sheet.pdf you'll see it's a fairly typical 350w into the bass driver and produces 124dB and actually goes quite low at -3db @ 56Hz. You'll also notice only the HF unit is Neo. Given the weight of the whole speaker this means the magnet on the bass speaker isn't that big. If it's 124db at 350W then it's just under 98dB/W sensitivity which is quite high/efficient. That all suggests to me that the compromise is that Xmax/excursion is limited which means high powered bass isn't on offer, The speakers are electronically protected so I'd imagine they won't get damaged just that the bass will be limited if you push them too hard. Having said that the limiting is on the input stages.... These speakers are a real bargain but you can't get everything for nothing so limited bass is the compromise. Are they usable? Yes if you don't try using them with a drummer with anything other than a light touch. However if you had two or more of them you are probably in business with an extra 6dB to play with. Alternatively if your PA is good you'll hear the deep bass from there and you can roll off what is coming through your monitors which will spare the Altos a little.

Speakons are rated at up to 30A whereas 1/4 jacks are rated at up to 5A depending upon exactly which plug and socket you are using, there's a lot of variation. So the power handling of a Jack is 100W into 4ohms maximum. 200W into 8ohms. If you are dealing with anything less than the best quality jacks you can only down rate from this. They were designed for carrying phone signals. We get away with using them for speakers because it is the peaks that are 300W or whatever when we play the average power is way below that however using a component rated for a third or less of its specified maximum handling risks eventual failure. If the contacts are dodgy through age you are going to get some sparking across them too. In addition some Jacks momentarily short out whan you pull the plug out or plug it incorrectly which isn't great for your amp. Don't get me wrong, I'm the sort of old bloke who reaches for jacks for preference and ease but let's not pretend its something we ought to be doing. I used to wire safety pins into old style fuse boxes to stop them blowing mid gig, that wasn't right either.

Is that the cab I built on Sunday or the mad idea I floated at the end when we were packing up? My band have a short paternity leave situation ( the perils of playing with younger people ) so I've got a cab built and no expectation in the next couple of months of a gig to try it at. If someone close by fancies a run out with a tiny 12" cab and I can get it to them I'm up for that.

I assume you mistyped. Epifani? anyway the only thing I got on a search was a Diego Epifani's Naples phone no! Who needs Cambridge Analytica that's a big magnet which implies a well damped speaker. I looked on Friday at buiding a cab for a 10" speaker with a smaller magnet than that and the cab came out smaller than this cab. Without the details I can't be completely sure but my best guess is that your speaker would be better in a smaller cab. It might be worth your while contacting Epifani and seeing if they can give you an more details of the driver. If they'd let you have the Thiele Small characteristics we could design you something quite decent.

Hi Stew, I put this on the wrong thread. I'll try again in an hour or so and get back to you then.

posted in the wrong thread

Try the Peavey IPR 1600 it's light as any lightweight bass amp and has combi sockets on the inputs. Mine have been 100% reliable and from memory its about 400W RMS into 8ohms 1600 bridged.

Off to the gym now Baggy T shirt next time...

Now you know where my waistline in the video came from

Sorry I can't resist and it's probably not what you want to hear. Why Class AB? you probably think there is a 'digital' sound? Honestly you won't be able to hear a difference, all else being equal. Your bass amp is made of three parts, a pre amp that shapes the sound, the power amp stage that makes the watts and a power supply that... supplies the power for the amp. The two things that primarilydetermine the sound of the amp at high power are the pre amp shaping and whether the power supply is adequate for the job. I'm not telling you all amps are equal, just that the class of the power amp isn't the critical factor. You specify a compact, and I'm assuming lightweight amp. They only achieve this if they have a switch mode power supply. Anything with a big and heavy old style copper wire transformer is going to be big and heavy by definition. If you have a lightweight switch mode power supply then you might as well have an efficient switch mode amplifier. If there was a difference in heft (there I said it) between the old heavy amps and the new switch mode amps a lot of that is down to poorer power supplies than the more mature designs of the old class AB amps. There are later models of class D with decent supplies. I don't know of anything with an old heavy power supply and a class AB power amp but maybe someone else will come along with a suggestion. It doesn't matter, audition a range of amps, if the only ones that sound the way you want are heavyweights you'll have to suck up the job of carrying them but I think you should give the newer amps an audition. Just think, if you play a big venue your amp is just a stage monitor, the bass you hear at big concerts comes from the PA and that will certainly be Class D. You'll never get that big a sound with your bass stack. Actually I've just noticed you wanted to bypass the pre amp, why not just buy a PA amp, run it straight off whatever you are already using, your sound but louder. Cheaper than a bass amp with a pre amp you don't want to use anyway.

Many thanks to Mike and his family and friends who did all the hard work. I hope they enjoyed it because for the rest of us it was so much fun.

There are lots of plus points about going lightweight though. The HA3500 weighs more than my cabs and it's getting long in the tooth so needs the odd repair every now and then, it is very noisy with the graphic switched in and the fan is so noisy when you are playing at low levels. I still love it but it's not reliable enough for me to trust it at paying gigs. I did contemplate buying one new when they were on offer a while ago but the MB Tube is fine and 100% reliable.

Thanks guys, see you tomorrow.

I moved from the HA 3500 to the MB Tube. Whisper it quietly (if you can hear a whisper over the Harke fan) the Hartke sounds better.

Thanks Mike sorry about the late notice, some of you will have seen me promise this on another thread over in Amps and Speakers. The problem was we got booked for a gig and I didn't think I could make the bash, then our guitarist had a medical problem so we cancelled the gig at the last minute. I'm going to attempt a basic build of a 1x12 cab up to initial testing as a demo of how easy it is to construct your own speaker. What I'm after is a continuous video of the whole build. I can bring a tripod so the camera can just be set up to run or someone keen would be welcome to be more artistic if they prefer. I'm hoping to do the whole build inside an hour but I've never done this in front of anybody before so it'll be interesting to see how quickly it can be put together, I'll try and answer any questions as I go. I'd be really grateful if someone could help out for an hour. Phil

Hi, I have one of these, It was on a special offer when I bought it a few years back and I think I paid only about £30 more than the LM III was at the time, otherwise I'd have gone for the LM III. The valve preamp is very subtle in it's effect, you aren't going to get valvey overdrive but it does add warmth. In practice I have the valve up full and solid state turned right down so I guess it must be useful. I didn't realise it had phantom power ha ha, I just plug it in and go but I have used a mic to get some percussion through the cab and that works OK. I'm probably not the one to comment on tone, I just use it flat most of the time and only eq for room acoustics. For me the amp does what it says on the tin. I can go as loud as the drums without overload with a couple of 12's and it is completely reliable. The VPF filter is useful at home and you can dial in some nice tones fairly simply but in a live situation I just turn it off usually to get a bit more penetration for the bass. I can only say you should try it out and see if you like the way it sounds with your own gear.

I designed something similar to that cab back in 1970, before the days when we used Thiele Small and computers had their own rooms and used punched cards. There were many such designs with effectively a conical horn built on the back of the cab with the expectation that the efficiency of the horn would enhance the bass and make the cab 'long throw'. In those days speakers were generally limited to around 50W for a 15" speaker and amps were really expensive so we were mainly looking for high efficiency rather than fidelity. There was a lot of trial and error involved! I suspect there wasn't a lot of calculation involved in the RH115 and Win ISD wouldn't be able to calculate the effect of horn loading on the cab. In my 'design' I got lucky. I was working late when someone needed some speakers and the only things to hand were my half finished prototypes. I hadn't finished making the rear horn so I bodged a simple unfolded horn and sent them out, they sounded so good compared to a lot of the **** available at the time that I quit when I was ahead and sold a few to disco's quite successfully. Looking back I don't suppose they probably only worked as bass reflex speakers but people liked the horn look of them. Just enjoy your cab, it might be worth something someday, people like the old school sound and most of the drivers were long ago replaced with something with a bit more power handling, they could become collectors items.

I'm just a little concerned here. If the original tweeter is a piezo it isn't likely that it has a crossover or that if it does it will match a 'proper' horn driver. People seem to be implying that early Markbass models used a piezo and later ones a coil driven unit, which would have had some sort of crossover. You really need to check before you start swapping things around. Without some sort of crossover the bass will go through the replacement tweeter and destroy it as soon as you play at volume. Piezos have high impedance at low frequencies and so filter out bass by their nature, this saves the cost of a crossover and is one reason why they are so cheap. If it is a coil/magnet based compression driver and horn in your speaker then any replacement would need to match the spec of the old unit fairly well in terms of sensitivity, impedance and power handling at least. It looks like others have used the HT30 successfully so I'd copy that mod in your position, but check first.

Coincidence, I went on to put up a thread about going naked, and here one is We gigged on Sunday with my occasional duo. Beer festival where we were on last, the previous guy was still playing when we arrived and the place was packed, Little time to set up and minimal soundcheck and we were stuck in an alcove next to the smokers escape route on one side and the gents on the other. Tight enough space that people kept knocking into my bass which didn't enhance my timing. On top of that the acoustics were awful and we couldn't really hear the backline. Three songs in the landlady had a complaint about noise and asked us to turn down so we lost whatever balance I'd achieved earlier. We survived and the audience seemed to enjoy themselves but grrr.... So Monday was spent setting up with no backline, I thought my mate would spit his dummy out about his guitar 'sound' but he'd found that gig as stressful as I did and was happy to give it a go. I like to keep things simple live, so we went for using the same monitor mix as the audience mix. To be honest it was total bliss. The bass sounded great through the monitors, acoustic guitar was the best sound ever and thanks to a G1XON so did the few electric guitar parts. BV's were so much easier to judge when you know what the audience are hearing too, I can sit in just under the lead vocal with confidence now. With the mixer sitting between the monitors we can fix everything immediately and turning volume up/down needs just one twist of a knob. So what gave the great bass sound? Bass straight into the mixer and two Behringer 1320D floor monitors.