Phil Starr

I was so pleased with the reaction to this. I started off with a collection of the BassChat builds we've been designing and publishing on here. I'd set it up to give me time to set up the shootout and the 6 was a last minute addition. and I hid it amongst the 12 and 10" cabs. I tried them all out with my Peavey Minimax and left the 6 plugged in. I think it was Rich who played it first. To be honest when he kicked off I wasn't certain which cab it was myself and had to sneak a look a little twiddle of the tone controls and it sounded great at what was quite a volume. I've loved playing this at home for practice as it does sound nice in a small space but this was something else. It's a single 6" speaker (Fane 6-100) in a 10litre cab made to match one of those little guitar amps you buy for your kids when they start out. Anyway it's designed to be as loud as possible but sacrifices all the fundamental with a nearly flat response down to 75Hz which means it will give a strong second harmonic down to just below bottom E. It also goes up to 7kHz so doesn't need a tweeter for bass and so avoids crossover distortion and all the unnecessary tizz of a cheap horn. It will do 93db/W and handle 100W thermal so can reach 113db with some limitations at the bottom end. Anyway that's the technical bit I'll let @Richand @stewblacktell you what it sounded like as I'm biased. This is what it looks like (grille removed)

you are going to get bored with graphs this is the Scorpion in the 'recommended' flattish ported cab compared with a slightly smaller sealed cab. You can see that the sealed cab makes a lot less bass. -3db is just above 100Hz so you are missing quite a chunk and there is about a 5db difference all the way down the bottom octave. It'll still sound like a bass but you can see why most designers go for ported cabs. It's a lot of free extra bass. Of course the slow roll off you get with a sealed cab makes them work well with a traditional bass boost but the cab will also affect excursion limits and power handling. On the plus side the Scorpion is a really sensitive unit making lots of sound for a few watts and it is tolerant of a lot of different cab sizes. Maybe you need to tell me how you intend using it, if it is just for home use them maximum volume is not going to be an issue and the neighbours and family might appreciate a bass light sound.

It is always good to re-use. I'm really happy that over the weekend somebody took my old Peavey Black Widow and is proposing to use it. Lets do the rest of this on the other thread.

hi John, I'll try to write something up whilst I still remember. It wasn't a formal shoot out this time with the numbers we had and the fact that i forgot to bring the sheets which would have made it a blind shoot out but we had a lot of time to compare cabs and talk through some of the differences we could all hear.

That should work fine.

Hi I've put the parameters you sent me into WinISD and it has come up with a recommended 82litres as an opening option, basically to give you the flattest response in a reasonably sized box. I've also modelled it in a stupidly small box of 30l and a really large one as a way of you seeing the options open to you. The darker green is the large box and shows you can get an awful lot more bass from a bigger box, not really a surprise It's also not a flat response. Light green is the 82 litres which is flat'ish 1db down at 100Hz and then rolls off gracefully with -3db at 70Hz and -10 db at 42Hz roughly the fundamental of bottom E. Red is in the 30l box which is really much too small for a 15. It is 3db down at 93Hz and has a hump at 150Hz. This all illustrates the first question you need to answer, how much bass are you willing to compromise for making the cab room friendly. This is the same for all ported speakers, a big box gives you more deep bass and a small box less bass and a more or less pronounced peak ultimately giving you a boomy upper bass sometimes described as one-note bass. FWIW most of my cabs for 15's tend to be around 60l or slightly bigger and when you measure the original cab I'll suspect it will be around that volume, it slims down the cab without losing too much bass or ending up boomy. If you post it up I can look at the figures and put it into WinISD and we can see what Peavey did. You like that sound so its a good starting point.

I've just been asked the following question about designing a cab for a Peavey speaker and I'm going to keep this away from the original thread which might be interesting for people to follow as a piece of design. Copied from the Easy Build 12 thread: Any way to easily adapt this Easy 12" design to a 15"? I have an old Peavey combo I want to rehouse the amp and speaker separately. The reasoning is 3-fold. Reduce the weight as the Peavey TKO 65 is heavy AF for a simple home practice amp. Also having the 15 as a separate cab will allow the use of other amps. Lastly its sort of ugly sitting in the living room. Speaker is a 15" Scorpion and assuming info from Peavey is correct for entry into WinISD: Impedance: 8 Ohms Power capacity: 800 W Peak 400 W Program 200 W Continuous Znom (ohms) 8 Revc (ohms) 5.54 Sd (Square Meters) 0.084 BL (T/M) 17.10 Fo (Hz) 50.1 Vas (liters) 132.4 Cms (uM/N) 174.5 Mms (gm) 70.30 Qms 6.05 Qes 0.345 Qts 0.326 Xmax (mm) 3.1 Le (mH) 0.3 SPL (1W 1m) 98.7 No (%) 4.70% Vd (cu. in. / ml) 13.9 / 227 Pmax (Watts pgm.) 400 The existing TKO 65 must be completely undersized for typical WinISD 15" driver recommendations, yet I do like the existing sound just fine. I haven't cracked it open yet to measure the existing internal volume. I am hoping to end up with a smaller cabinet design like the one from this thread that I can build up out of poplar and stain to integrate into the household. I have a woodshop/tools at my disposal and the requisite skills. (I've even done dovetails for a Vibrochamp clone in the past.) So it is really just the design stopping me at this point.

I'll get back to you on this with some thoughts later, busy today OK initial thoughts and a couple of questions for you. I've started another thread to keep all the information about your 15 together. Rehousing a Peavey Speaker - Amps and Cabs - Basschat

I hope we aren't putting Bluemeanie off, he just wants a working speaker. This is really helpful to me however, thanks. My experience is of just a few failed units that I successfully repaired. In all three cases the dust cap had come away partially from the cone. The neck joint wasn't a problem in these limited cases. Just one of these drivers had the metal dome the others were fabric domed versions. In each case the adhesive appeared to have crystallised, forming hard granules which crumbled away easily from the cone/surround. I only discovered the partial separation of the surround from the basket when the speakers were removed from the cabs. they were both rear mounted. I each case the glue showed the same crystalline structure and was crumbling. All the speakers were of roughly the same era and were already 20 years old. I have to say I loved the sound of those old metal domed Peaveys. My first proper gigging speaker was a 2x15 Peavey and I loved the sound it made.

I had three of these that needed repair to the dust cap of which two had the same issue with the surround. That was out of five I had over a couple of years but those speakers may well have been from the 80's too. I have no problem with a speaker that fails after 30 years especially when you can still get replacement parts. I hadn't come across the foam issue but it's useful to know about. I don't know if Peavey are still supplying the replacement baskets but over here the repair was uneconomic you could buy a speaker of similar quality for less than the cost of the basket.

You'd probably lose about 2db in volume, that's noticeable but not huge. 1db is about the smallest change you'd notice, so just a little more than that. I gigged this speaker in a home built cab for years with a Hartke HA3500 (250W @8ohms) and it was plenty loud enough for any pub gig. I bought it as a replacement for a Peavey 2x15 which had developed a buzz like the one you described but then fixed that which is how I know the stuff above. The 2x15 was borrowed so I returned it and used the 1x15 as my gigging speaker. I should have said the buzzing could be other thinks loose in the cab or worst case the coil is damaged which makes the speaker you have unusable as it would then fail fairly quickly. You can test for this by using a pint glass to gently push the cone in, a scratching noise would not be good as that says the coil is rubbing. Peavey BW's are pretty reliable though apart from the glue issue on old ones so my suspicion is that is your problem. £30-40 is the going rate for a replacement BW so that's the worst damage you could do. It's not a difficult job to do if you are careful so despite talking myself out of a sale I'd say give it a go. You've probably located the problem with your finger pressing.

Oh welcome to BassChat

You might want to change the title. If there are people out there with expetise in speaker repairs they won't necessarily see this. The glue in old BW speakers doesn't age gracefully, it hardens and goes brittle eventually breaking down. This is used in two places, to stick the central dome to the cone and to stick the cone to the frame. The repair is simple, glue it back down again. To do this without affecting the speaker means using a compatible glue and I use Copydex which is latex based. it sets to form a rubber bond which is flexible and it is compatible with the materials used. you can spot fix the offending bits but usually the glue will go elsewhere. I remove the dome completely and clean off al the old glue by gently scratching away at it then just copydex it back on following the insructions on the pack. the surround is trickier but it is possible to ease the surround away and re-glue that in the same way. Be careful here as it has to go back in the same place, any sideways movement might make the coil rub against the magnet which will kill the speaker. You could try freeing a bit at a time cleaning that and glueing then move on to the next bit. One thing that makes it easier is that you can remove the magnet from the BW's to service them, again with care. Alternatively I have a spare BW I'd be happy to sell, but this is an 8ohm unit. PM me if interested, I'm going to advertise a few bits on BC sometime soon but if you want it you can jump in now.

The reason they sell 4 and 8 ohm versions of the cabs is that there is a demand from musicians for more watts. Part of that is from people who like to be able to talk about how big their stack is, part is that there is a smidgin of science about it and part is because of people being utterly confused by the advertising departments into desiring lots of watts. The thing is that what you really want is sound levels, for want of a better unit lets say decibels. More watts through the same speaker will give you more decibels so long as you stay within the speakers operating limits. 100 wats through your Ashdown is going to give you louder bass than 50W. Just not as much as common sense might suggest. In fact with the same speaker operating within it's limits you'll get an extra 3db. Confusingly if you were operating at 1W you'd only need another 1W to get 3db extra volume. You've doubled the power and that gives you 3db. So now we go to your amp, theoretically it should give double the power into 4 ohms. and at low levels it will. Running at 1W you'll get the extra 3db into 4 ohms but at 300W into your poor amp will run out of puff (read current) and you will get 500W into 4ohms according to Ashdown. That's a lot of extra watts but not quite double the power so around an extra 2W. Confusingly though to make the speaker 4ohms you have to change the coil and that throws other things out. theory is simple the real world a bit messier. So how much louder is 3db. Well, it might be twice the power but it is nowhere near twice the volume. 1db is the smallest change you can hear, one click on the stereo, a just noticeable change, but if you left the room and you came back and someone had turned the telly down 1db you wouldn't notice. 3db is just about what you would notice. If your mix is right and you turn up 3db the bass would dominate, it wouldn't be silly but it would definitely be noticeable. Equally if the bass was just not quite there 3db would fix it, probably. These aren't iron rules, the sound engineer will be able to hear 1db changes and a ham fisted guitarist quite capable of adding an extra 6db wiping the balance out for everyone else. You haven't said if you like your tone? If so then there is a very simple fix, buy a second 8ohm 15. Doubling the cone area will give you 3db extra and the extra 200W going to 4 ohms will give you another couple of db. 5db will make a difference even the guitarist will hear!

oops double post

Yeah I'm not knocking the designs at all. I'm just interested in what other people are doing within a fairly tight envelope. I also thought it might be interesting to Teebs to know what he would be trading for what I expect would be a superior sound. He's intending using this with a low powered amp so knowing that option would be a lot quieter than his hifi would be important. My design was to work with a 10/20w amp so sensitivity was important.

You can see how they do it, Sensitivity is 86db/w for two drivers. That's fairly low for a hifi cab and very low for a bass cab. Those drivers will have heavy stiff cones, great for bass and I'd expect that they will sound good, just not loud. Most hifi cabs and studio monitors would go as loud and probably be cheaper, and available used if you wanted a cheaper route. Just for comparison when I designed the 1x6 I decided to go for high efficiency and to trade off the low frequencies so my baby does just under 93db/w and you'd need 50W with the GR speaker to match mine at 10W. That's just the iron law, it would be simple for someone else to design a medium sensitivity speaker of similar size with better bass than mine but not as good as I imagine the GR bass is.

So this is the output at 10W. You've got just over 102db. -3db is below 80Hz so you are getting a fairly flat response with all the second harmonic for bottom E and upwards which gives it a fairly rich sound for a tiny speaker. The speaker itself is rated 100w thermal so you can push it way harder if you use a 'proper' amp It would work well with something like the TC BAM but even at 10W it'll be a decent practice volume. I can send you dimensions if you decide to build it but it's 10l so about the size of a petrol can. It also goes up to 7khz so gives a nice clear sound, I've also tried it as a 'bright box' on top of a 12 and it sounded great both with and without a crossover. My next step when covid abates is to try it at an open mic. It'll never work with drums but maybe with acoustic guitar and a cahon and amplified voice it should be good. It's fun to play with too. Fane : Fane Sovereign 6-100 :: £37.09 (bluearan.co.uk)

OK hopefully this should be a recording from yesterday through my 1x6 using the Peavey Minimax as shown below. the amp was set flat but I couldn't tell you what the settings on the active bass were. I'd hidden the speaker between two bigger cabs and the person playing had no idea at first that it was a 1x6. Bass demo Fane 6-100.WAV

You might find this interesting, it uses the same driver but the cab remains untuned my design has a little more bottom end Pimp my practice amp! - YouTube

Here you go A House Jam Combo - Build Diaries - Basschat Interesting timing, I took it to the South West Bass bash yesterday where it created a bit of a minor stir. I hid it amongst some bigger cabs and got a couple of people to try it. I also recorded it and will put up the recording when I get some time this week.

I think its fair to say @wrinkleygitand crumble have a very special relationship

Well done, there's nothing like something you've done yourself. Some pictures would be lovely though

Anyone know what time we can get in?

that's great, Stevie isn't coming and I'm waiting for parts to make mine tweetered so it'd be great to have one for the shootout. Really happy about the video too. There's quite a few people have viewed the other one over the years