Jump to content

Dear guest,

Welcome to the biggest community for bass players in Europe. You'll find the site a great source of information and advice.

Why not sign up now and:

  • Say hello - tell us about your playing, your gear and where you're from.
  • Search the database for inspiration or to find out more about your instrument
  • Upload an avatar and profile picture
  • Buy one of the thousands of items in our marketplace
  • Safely sell your items to a community of proven enthusiasts
  • Upload pictures, audio and videos
  • Buy exclusive items at discount through our shop (coming soon!)

Go on, click the button and become part of it today!

New: Sign up and get 20% off tickets for the London Bass Guitar Show - and we'll see you there!

Phil Starr

  • Content count

  • Joined

  • Last visited

Total Watts

27 Excellent

Personal Information

  • Location
  1. Ported v sealed

    Hi Bill looks like our posts crossed. there's no doubts about the effects you mention or that the Q of the cab is changed by filling the airspace but I've seen all sorts of claims for 'damping' from the use of high density materials to kill panel resonances through placement to kill standing waves within the cab and so on and so on. We'll both be aware of some of the claims and counter claims about damping materials. Without decent software and test gear it's not an easy thing to be able to say put x amount of stuffing in this part of your cab. Some of the treatments I've seen in commercial cabs leaves the impression that they've done it just so it looks right. Kevin, my advice is to find an old polyester filled duvet and experiment with the material in that, Dacron is just the brand name. using the material to hand lets you do a lot of experimenting at little or no cost.
  2. Ported v sealed

    Hi Kevin, as a second opinion I'd say that stuffing an enclosure is a complex subject, I still haven't seen a complete mathematical model for this and adding damping materials is done in differing ways in different cabs to achieve a variety of outcomes. Dacron is a very light material and when thin nearly acoustically transparent. There's no doubt that it affects the response of the cab and generally flattens the response by damping resonances but the effects aren't huge unless you achieve reasonably high densities, you'd probably want at least a kilo of stuffing in your cab, keep it away from the ports. As to whether it will improve the sound of your cab I suggest you try it and stick with whatever treatment gives the sound you prefer. The bracing does look a bit haphazard though.
  3. Ported v sealed

    If you look at Bill's graphs it's fairly easy to see what is happening. Stuffing the ports to block their output cuts the deep bass by 3dB roughly. Cutting the bass makes everything else clearer, just as rolling off the treble makes your bass 'bassier' on top of that deep bass often sets off room resonances which can muddy the sound. We don't hear those very low frequencies that well anyway so don't miss them that much, in our studio recordings recently I cut everything below 50Hz form the bass, you could barely hear the difference on the isolated bass (sadly the filter added no talent) but it cleaned up the overall mix nicely especially on the sort of small speakers potential bookers are likely to listen to. You'd think that the more bass the better, but it ain't always so. Part of the 'sound' of the speaker, I'd argue easily the most important part is how it portrays the bits we can hear well, the mids. It may well be the Berg does mids similarly to the Trace, so happy days. Equally it may be that the lack of deep bass is an advantage in terms of clarity and punch, as I've explained above. Bill's response curves are of the same driver in sealed v's ported cabs, it's quite possible to choose a driver and design a ported cab which will have a bottom end that rolls off in a very similar way to the sealed cab in his example. The bass handling of a speaker is the combination of both the nature of the driver and the design of the cab The final part of the puzzle is that what we hear depends upon how our ears and brains work together to interpret sound. What we hear as bass is often sounds above 100Hz. Just turning up the mids and treble makes us think there is less bass. Our ears are so insensitive to 30Hz for instance that even if the speaker is good in that area we won't notice a 30Hz filter because all the other sounds in music drown it out anyway. It may well sound deeper if you port it and how it sounds to you and anyone else is what matters, not the output at one particular frequency. In this case however I kind of see what Ashdown are saying but I don't think it's helpful. If you go back to Bill's graphs then that is what they are predicting will happen with your cab. The speaker won't be any different above 200Hz as Bill says so it won't be louder. In his first graph you'll see just a touch more bass around 80Hz which you will notice (the exact frequencies boosted will be different in the Ashdown) but you'll get better power handling in the bottom octave which Bill shows in the bottom graph, so when you turn it up you'll be able to make more bass noise before it distorts with the ports. I'd say it will sound bassier to you.
  4. Basschat 1x12 - Frankenstein project

    PS a midrange driver is also called a squawker.
  5. Basschat 1x12 - Frankenstein project

    I don't think the hosepipe analogy works when you bring frequency into play. A speaker isn't a 'pure' resistor, as the coil moves inside the magnetic field it generates an electric current which is out of phase with the driving current which makes the impedance rise. So yes the impedance rises with frequency and bringing in a second driver at high frequencies shouldn't stress the amp. There are problems of just introducing a midrange driver with only a simple HPF. both speakers will be producing sound around the crossover point and because they are physically separated you'll get interference between them and response irregularities. That will depend upon the exact drivers, some drivers roll off naturally at fairly low frequencies and this approach will work OK, others will have a big midrange peak (like the Eminence Beta 12)and you'll get potential problems. The Beyma has a fairly flat response in the midrange. The truth is though that both speakers are producing equal volumes at the crossover point and you always get some crossover artefacts with passive crossovers. In the case of a simple HPF they are worse but lot's of commercial designs use them, rather than Stevie's 'proper' crossover. In a way it's only one step up from using an old school mix of drivers, but these are intended as instrument speakers and some people like a bit of character/response irregularity. I'm not aiming at FRFR with a design like this, just a DIY tweak that people can do cheaply and simply. As to the enclosure for a midrange it needs to be pretty much as small as you can make it usually. I go for a 'critically damped' sealed enclosure with a Q of about 0.5. More about that later.
  6. Weird Question but I'm kinda a noob

    I had to listen to check. Love the rhythm though.
  7. Basschat 1x12 - Frankenstein project

    One of the advantages of a mid range driver is crossing down at a lower frequency, a 12" speaker is already beaming at 1kHz. the larger driver will usually handle more power than most compression drivers too. Years ago I bought a couple of 6" units to try with the Mk1 Basschat 12 but never got around to trying it. I had planned originally to build it into a separate sealed cab and try it with an active crossover to find out the sweet spot for the crossover, I was also going to try it with a 6dB/octave high pass filter built in to see if it could be offered as a design to owners of other cabs to use as a kind of 'bright box'. The downside is that even a 5" driver starts to beam at quite low frequencies and operates under cone break up above this so you won't get as clean a top end as with a horn tweeter. You kind of have to decide whether mids or the top end are your priority. There's an alternative to consider , which I wish I had built at the time to get bragging rights on Build something like the mini line source speakers that are described in the recently closed Markbass thread. Using a 2 or 3" driver would be ideal for bass. It'd go high enough to cover all you'd need in the way of top end but would let you have a lower crossover frequency so the mids would have an equally controlled dispersion. The downside is that a single driver that size wouldn't be loud enough. However a line of four would give you the increased power handling and efficiency you'd need and as a bonus a vertical array of drivers would give you a nice wide, flat, fan shaped radiation pattern. Someone beat me to it https://www.genzleramplification.com/shop/bass-array12-3/ I'm still looking to do this as my next project, if you want to go ahead then I'd be really interested in helping, and it may stimulate me to actually get into gear and build the one I've been planning for years.
  8. Speakers - Displacement

    I hope this hasn't been too confusing so far All of the information given so far is good but I'm not sure how easy it is to follow. I think you may have a mistake in your question, if you change it into ' if I have one cab A at 200 cubic cm and cab B at 450 cubic cm, is cab B louder? Is it moving more air' then it makes sense. Displacement is the volume of air displaced when the speaker cone moves through it's full undistorted range. In this case the answer would then be yes, it moves more air. As to how important this figure is, well it's one figure amongst many, it's important but not without all the other figures. Barefaced use it a lot in their adverts because their drive units are very good in this area and Alex Claber regularly posts in this forum so it has become a significant quality factor for many people. To be fair I don't think he has ever claimed it's the only important factor or made false claims but some of his fans have jumped upon it as being the key figure by which speakers should be judged. Over the last couple of years it has become a figure people on BC have fixated upon. I'm going to use the car analogy I'm afraid. The volume displacement of the speaker is like the capacity of the engine, it's the piston area times the stroke length. But , the cubic capacity of the engine won't tell you its power and the cubic capacity of a speaker won't tell you how loud it is. That also depends upon how efficient the speaker is, not all it's movement is converted into sound. A 2 litre engine is likely to be more powerful than a 1litre engine but you will know that isn't always true, I've just traded in my 1.6 litre VW for a more powerful 1.0 litre Vauxhall. If Vd is too low then your speaker isn't going to be able to make lot's of undistorted bass. If your goal is a small loud lightweight speaker then high excursion and therefore Vd becomes very important. If you can't displace enough air then you can't make sound above a certain volume and bass frequencies need a lot of air shifting. If I was designing a 10" high performance speaker I'd be proud if it had Vd Another factor though is efficiency. If you double the cone area and keep everything else the same then you'll get an extra 3dB for the same power. It's quite possible for example that if you took two 10" speakers with Vd of 200cm3 they might be louder at 300W than a single 10" speaker with Vd of 450 cm3.'t I couldn't tell you for sure without all of the figures. The physics of speakers isn't that hard, if you've got 'A' level science or maths you'll have no trouble, GCSE maths is enough if you are interested enough but plucking any single figure out of the air isn't going to explain much, you have to do the maths. I the end I don't think Vd is very helpful to the average bassist. Yes it's particularly important that small speakers have good excursion but in the end that won't tell you how they sound. You wouldn't buy a car without a test drive or choose the engine size without considering other factors first and I don't think you should choose a bass speaker like that either.
  9. Singing Tips for the Reluctant

    No, I'm incredibly old but never smoked, no health issues and I'm pretty fit, gym and cycling/walking. Any YT coaches you'd recommend, there are sooo many it's hard to know, and they contradict each other a bit.
  10. Singing Tips for the Reluctant

    I'm finding this whole thing strangely affirming. All the nerves every time I have to sing (BV's only) Finding out you have to practice and learn to sing, who knew? I had the experience at school of the music teachers who either wanted you in the choir or didn't want to know. In my case they listened to me once, told me I couldn't sing and had to drop music, a bit hard on an 11 year old. Probably as a result of considering myself a non-singer I'm finding the embarrassment factor quite a problem. Particularly the thought of going to a tutor and having someone actually listen to my voice is slightly more intimidating than walking up Oxford Street totally naked. So it would be great to get as many practical tips as possible. The thing I'm having a real problem with at the moment is Elbow's 'One Day like This'. If we are to do this as a duo I have to sing the 'throw those curtains wide' bit. I can hit the notes but can't hold them for more than a couple of repetitions of the line. I get the build up of something on my vocal chords and my voice starts to make odd sounds. I need to cough and then can't sing a note reliably for the rest of the evening. It happens elsewhere but only temporarily and a quick cough clears it. Any ideas? It feels like something mechanical. My one tip for anyone starting to sing with a band, get a good personal monitor. Knowing you can hear yourself better than anyone in the band or audience really helps.
  11. Markaudio linear array systems

    PS I was getting a bit bored with so many anodyne threads running at the moment. It's nice to have a topic to get our teeth into which is also informative. Nothing wrong with a bit of passion so long as people remember their manners?
  12. Markaudio linear array systems

    Oooh that sounds interesting, well worth a drive for me too.
  13. We're off - 1x15 DIY

    I love a happy ending, well done.
  14. My bass life winding down?

    Still hoping this story has a happy ending, which is that you find a band that needs a bassist for a few gigs. It makes me realise how lucky I've been picking up the bass late in life and going pretty much straight into a gigging band. It's funny how bassists are like the hardened drinkers in the pub, we all want someone to share a drink with us.
  15. Minimum size amp for gigging?

    Always trust the bloke in the pub Without getting too technical Watts are Watts so long as they are measured in the same way. It isn't to do with class A/B or D. However some amps do have bigger power supplies and that will enable the amp to produce it's full power for longer. A lot of early implementations of class D had poorly rated power supplies fitted so they didn't provide their maximum output for long. That was true for a lot of early solid state designs back in the 60's and early 70's too and cheap amps ever since. Given the weight of Trace Elliott stuff I'm guessing large power supplies and big speaker magnets were the norm and that's probably why people loved them. No magic, just decent engineering.