Phil Starr

That's it really, I'm using it with the mains lead going in through the port at the moment. Let's not carried away, it sounds OK but there is almost no deep bass, a little warmth above 100 Hz helps but that is the point really, it doesn't annoy the neighbours as normal house structures are fairly good at containing the higher frequencies. It keeps up with two of us singing and my duo partners unamplified but enthusiastic acoustic guitar, it takes up very little space and it is plug and play. All the donor guitar combo provides is the amp and a ready made cab. Surprisingly the 10Watts advertised is actually 18W into the new 8 Ohm speaker and that is plenty. I'm contemplating replacing the power amp section with something that runs on a car battery and i need to move the IEC mains socket on to the rear panel but i'm happy that this was an experiment worth doing. Total time was about 90 mins over a couple of evenings

As a first step I cut a piece of ply to be a tight friction fit in the open back, I knew from previous experiments and from theory that you wouldn't get any bass when the sound from the back arrived and cancelled the sound from the front of the speaker. Actually sealing the cab made the original speaker sound a little better but I found that I could just drop the new speaker in so i did, total time so far was about 20 mins. this was getting there but was still bass light. Off to Win ISD to model the speaker in it's new cab. I used a hole saw to cut a hole in the ply and a hacksaw to cut 93mm of plastic drainpipe.

As you can see it was an open backed guitar cab just about 30cm tall. Ignore the speaker inside it had something much smaller which looked like a car speaker from the 1970's and not in any good way. Here's the speaker next to it's replacement, as you can see the original speaker had a tiny magnet and what you can't see is the flimsy cone. It was rated at 20W handling and 4ohms. the replacement was a Fane 6-100 rated at 100W but crucially with a heavier cone, good excursion limits and a proper magnet. Despite the slight loss of power this was going to be a little louder due to the larger magnet driving it harder.

Hi All this has been stimulated by two (thanks for the impetus @Pea Turgh )of us having the same need, for a tiny combo for 'quiet jamming'. Most of us will have had the same problem, even an acoustic bass just isn't loud enough when someone else starts playing a guitar and singing and maybe those wall are just too thin so any deep bass goes through them as a deep and annoying thud for the neighbours. In my case it was a stay in a rented holiday flat. I grabbed a tiny 10W guitar Combo I'd bought for my son about 20 years ago which had never been used. It did the job in that he could hear me but it sounded awful, it didn't have very little bass it had no bass at all and it was only loud enough because of the nasal tone. I wanted something just a bit better but in the same fomat, really tiny and something that would plug and play. Here's what I started with.

Hi Pete, I'll get back to you later. I've just done this with a guitar combo of my son's, never used. It's still not brilliant but it'll do bass at a sufficient volume to play along with an acoustic guitar. It just involved a simple cab mod and a speaker swap. Camera's broken on my phone so it'll take me some time to show you what i did. I'll try and make some time this evening.

Following this with interest. I've nothing to offer in the way of tips, I'm hoping to learn. I always thought I couldn't sing and I still don't do much but with band members desperately searching around for someone to do something to support the song I've very tentatively given it a go. By describing myself as a non-singer I mean awful. I was told not to sing in assemblies or lessons as a child. My own kids fall around laughing at my attempts to sing and I had nothing but negative comments for 50 years at least. However I discovered I could hold a note with decent stage monitors. It's not a nice sound but it is in tune. I started off with one chorus and one song. No-one threw anything and my duo partner was encouraging and gradually I've added in bits. The moral of the story is that it gets easier with practice, I only do backing vocals, my range isn't great and for some reason I struggle with songs in E or B, also vowel sounds. On a good day I can sing in tune without monitors but only songs I've practiced. I've never thought of singing as a learned skill, I assumed you had to have some talent and I know most people find it easier than I do but when I do sing the audience join in and when I don't we get less of a response. Give it a go if you are a non singer, wherever you are at you can improve.

agree with Bill that the Trace are using probably some version of the 8PR200 http://www.bluearan.co.uk/index.php?id=FTP8PR200AP&browsemode=manufacturer they are on offer at the moment but retail on them is around £200, that's just the speakers of course, by comparison the barefaced super compact has a variation of the Eminence Kappalite in it again around £200 but with a more complex cabinet than the Trace cab. On balance there is roughly the same sort of mark up. FWIW we ran a blind comparison at a bass bash last year down in the South-West and one of the contenders was an MB12, probably the one you are looking at. It was the marmite cab with about 40% of the bassists scoring it top and the rest really hating it. It was a classic smiley face cab lots of tops and a really warm full bass due to a peak at around 100Hz but not much really deep bass. It was run off against much more expensive speakers like the Fearless 12. I didn't like it much but it would sound good in a band setting and an object lesson in a good sounding cab at a reasonable budget. That's why you have to listen to cabs.

I know it's difficult in the current emergency but this isn't the best way to choose a cab. I won't say size doesn't matter just that it doesn't matter much. You really need to go out and listen to these things, not all 12's sound the same or all 2x10's and the same applies to 8" drivers. There are a few design considerations connected with cone size but you are buying, not designing these cabs. I guess there's a little worry about the concept of 8" speakers for bass. There is no technical reason why the cabs can't work, sure there is less cone area and the cones are likely to be stiffer and lighter but all the problems can be designed out. You've probably listened to your favourite bass tone at home on the hi-fi and it sounded great, my guess it that this will have been with an 8" or smaller bass driver. an 8 can do a low B if that is an issue for you. A couple of 2x8's vertically stacked is an appealing concept to me, it's not just weight that makes things difficult to carry, larger cabs still tend to bang your legs and doorways even if they are lightweight. Go out and have a listen, you may end up crossing 8's off the list just because no-one has yet designed a cab with your sound, with 2x10's and 12's you have more choice but there is only one way you can decide and it isn't on the internet. Good luck with the search.

Here's the original ad

I was browsing the amps and cabs for sale (lockdown boredom) and came across a Trace horn cab. A kind of bright box but with what seemed to be a single driver with a wooden horn cabinet rather than the 4x small speakers most people would recognise as a Bright Box. I haven't been able to find any details on the web other than a couple of not very informative pics. I've been toying with the idea of building a midrange horn (more lockdown boredom ) and wondered how well they worked; possibly not great as they didn't seem to sell many. Anyway does anyone have any experience of them or better still any pics to give me an idea of what went on inside. Here's the pic

another really interesting bassline, a bit more sophisticated this and this one I know. Andrew Powell https://en.wikipedia.org/wiki/Andrew_Powell look him up and you realise he knows a bit of music theory! Wish I did, so much for the idea that knowledge stifles creativity

Perhaps guitar solos belong at the end. Whoever the session guys were on this they did a great job. Fun bass line too.

I think that's unduly pessimistic. As of last week there was only one confirmed case worldwide of someone definitively catching a second dose. There will have been more but very few people have been reinfected to date. That's normal for viral infections. Don't forget that immunity is more complex than just the antibodies and you wouldn't expect the body to go on making unnecessary antibodies. In any case we already know that vaccination produces better immunity than the disease. That's true generally of vaccines and specifically of this one and the Astra Zeneca one (probably of the others but I've not seen details). The reality is that all we need to do to eliminate COVID is to get the R-rate down below zero and hold it there, that is an extinction event. For that we need roughly 65% 0f the population immune. So with a 90% effective vaccine we need 70% coverage and the population becomes immune. As to venues opening up that depends upon political will. There is going to be a huge demand for the things we've missed and those hospitality businesses that have survived will do well. Let's hope that the government has a plan for repairing the economy driven by public support. We all need those jobs whoever is in power.

Well it was a few weeks earlier than I thought. Yesterday's news might mean we are back on for a completely safe bash in the summer sunshine. What a celebration that will be

Yeah this is a really serious point and could be a significant moment. Moving through another species is probably the most likely way of the virus mutating as it will come into contact with new viruses and particularly any mink corona viruses. I'd have placed anyone who has been to Denmark into mandatory isolation whilst the numbers of infected people is minimal. The chances are that it will come to nothing but it's the sort of event we should be anticipating.

This is fantastic news, there are two other vaccines which are looking good and should be reporting soon and 10 in phase 3 trials altogether. To put this into perspective if the vaccine does turn out to be effective at 90% and Pfizer delivers on 50M doses this year and over a billion next year we are going to be well on the way to the old normal. 90% would mean we'd achieve herd immunity with 75% of the population vaccinated. With an end in sight it makes real sense to look after each other with sensible hygiene and infection control. It would be really beyond sad to lose people when the end is in sight like the poor souls that died in Nov 1918. Let's not rush our fences but having predicted the pandemic in Jan and a vaccine by Dec I'd tentatively expect us to be gigging again this time next year and probably by late summer. Let's hope this research stands up but it is looking good. I confess I was tearing up when I heard the news.

What a lot of female singers

I'm a scientist, nothing is certain here but the trials are genuine, I've been tracking them for a while and there's been some recent press work from Jeremy Farrar of the Wellcome Foundation. I think there is a genuine possibility of a route out of this based upon vaccination. I think there is some cause for hope of an end game. The politicians may well be failing to understand what is happening and the media are certainly misreporting but there is plenty of genuine science going on. Always be a sceptic but having called this one from the start I'm starting to have some optimism. My feeling Keith is that there is a better than 50% we will be able to discuss this over Mrs Scrumpy's food sometime later this year. I'm not saying when though.

You could just about get away with Eminence beta's. on the eminence site there is a design for them in a 20l cab it would give you a 3dB peak at about 120Hz and a roll off below there so it will be 12db down at 50Hz, not much deep bass but with a bit of punch leant by the 3db peak. Given that the beta has a very marked peak in the upper mids above 1kHz that is going to give you a real smiley face response baked in, that might be the sound you like. 3mm excursion limit isn't great and you can get more for your money by buying European made units over Eminence Bass response in 20l cab frequency response curve from Eminence website

It might be fun to design a 4x10 for you. It'll be a good lockdown project. I'm sure people will contribute all sorts of ideas. The cab you are proposing is kinda small, around 85litres if these are the internal dimensions even less if they are external. Any reason why you have chosen this size? Do you have a budget in mind? Any thoughts about what sort of sound you are trying to achieve?

There are 9 phase three trials going on at the moment which will all have results coming in during Dec. They may not be perfect but they look so far to be safe and at least reasonably effective. So long as they are safe and deployment is well organised then next year could be a whole lot easier. If only 50% of us get high levels of resistance to the disease then the R rate could be halved. Expect key workers and young people (who are the main spreaders of the virus) to be treated first. Geriatric bassists may have to wait a few months Having been told I was alarmist and mistaken back in February I'm now cautiously optimistic. I don't think it will be over by spring but it should be looking a little more hopeful. I can't wait to see you all probably later next year.

I love it, a thread derailed by a nice bassline. A bit like my life I said it was a basically simple pattern (root/fifth/octave, as pointed out) but such lovely touch and timing. For me the key was the shift to starting the runs at the end with my index finger and playing the third up the neck as he does in the ending. Still haven't used the extra octave in my version, I need to work on that. Quiz question which is the Tommy Cogbill bass line we all know? Funnily enough the other example I nearly used was this one, I hadn't seen Preacher Man on Muzento that would have saved some time as this did.

It was an interesting question and an interesting read. Reassuring that most bassists playing covers adopt the same strategies that I have. You have to be on top of the feel and structure of the original but adapt your line to the band you are working with and your own skill set. I've only ever played in covers bands and at the peak probably had 150 songs with three bands that I might have to play at a moments notice. Between them we'd be learning maybe 3 or 4 new songs at any one time so you have in any case to have strategies just for coping. Don't let people see your feet furiously paddling under the water 'Beginners thing' is too pejorative. It's a learning thing I tried to learn the note for note bassline to 'Son Of A Preacher Man' recently, I didn't succeed because in the end the band just needed to get on with it but it taught me a lot about how a fairly simple pattern can add to a bass line and forcing myself out of the same old same old has freed up the way I play other songs too. There's loads to learn from other people's bass lines. we are all beginners

this shows pretty much what Bill is talking about and i happened to have it on screen. I'm designing a speaker for a practice amp and this is a plot of the maximum power handling for a 6" speaker. The flat line at the top of the graph is where the power handling is limited by the heat in the voice coil (100W in this case) Between 100 and 250Hz the speaker has to move a long way to move the air so the speaker can only handle 20W without distorting. The flat bit at around 90Hz is where the port will be making the sound and the speaker stops moving. Below that the speaker is effectively in free air as the port stops being a barrier and the power handling drops to almost nothing. This is a tiny speaker I'm proposing to use with a battery powered amp so it's fine for this job but the general shape of this graph will be the same for most drivers. Speaker manufacturers quote the thermal limit because it's easily measured and checkable. The rest depends upon the cabinet and frequency so they can't really give a definite figure but the cab designer can work it out. You don't really need to know this to buy a cab except that it is useful to know that sounds below the port frequency can damage speakers if you drive them hard and that driving any speaker to it's thermal limit isn't great.

Hi Jack, you have it right, more or less. the 6dB gain is made up of two parts, there's a 3dB gain due to the halving of the impedance and the amplifier providing double the power (if it can, more later) The other 3dB is due to the increase in efficiency of converting the cone movement into air movement by doubling the cone area. Which is available simply by adding the extra cab. The complexity is in the amp. The amp provides a voltage across the speakers which determines the maximum power but providing tht power continuously depends upon the power supply built into the amp. If you move from 16ohms to 8 then the power will almost always double. For most commercial bass amps if you then halve again to 4ohms then the power supply won't be able to provide enough current and the amp won't quite be able to double the power. Typically most current amps will do something like 300W into 8ohms and 500 into 4 so the increase in power by doubling will be more like 2dB than 3dB and the increase in sound nearer 5dB than the theoretical 6dB. A few designed for 2ohm operation will still double at this point but will then run out of the ability to double the current going from 4ohms to 2. Power is voltage x current and the power from an amp can be voltage or current limited. The Barefaced is interesting as it has a crossover inside so the switch from 4ohms to 12 is achieved by changing both the crossover and the wiring of the speakers. Quite slick really. Impedance in any case changes across the frequency spectrum and the ohms quoted are for any speaker are an average. So to answer @alexa3020 's question. doubling up the BF 210's will give you extra volume. How much will depend upon the exact design of the amp you are using. You'll gain 3db from the extra speakers but how much power you will lose depends upon whether the amp is current limited or voltage limited at 6ohms. My guess is that it will be voltage limited and will provide roughly the same power into 6ohms as it will into 4. Overall you'll be 2-3dB louder, but it isn't as simple as this. By adding the extra cab you are going to lift the top speaker to ear level and changing the radiation pattern for the audience. You are also reducing the current and power to each of the 10's and this reduces the amount they heat up and power compression at high levels as well as distortion. There will also be changes in the coupling of the speakers with the floor as this is dependent upon the distance of each driver from the floor. The important thing is how this sounds. Adding the 2-3dB isn't huge but will be noticeable but I think you will experience a cleaner sounding and more authoritative sound and you'll be able to hear yourself more clearly above the band. Two speakers stacked vertically is a lovely experience for a bassist and if you can afford it then it will probably become your go to setup even at smaller gigs.