Chienmortbb

[quote name='geoffbyrne' timestamp='1496148395' post='3309115'] ....or, could someone suggest a comlimentary port to cut in an Ashdown Mibass 12" cab so the Beyma works properly? I think the porting is the problem, the cab isn't 'breating' smoothly at low frequencies. G. [/quote]Geoff is it this one?

[quote name='geoffbyrne' timestamp='1495907223' post='3307512'] Hope not to derail..... I have a Beyma 212 - but am totally hopeless with tools. Anyone building these cabs for money? G. [/quote]As Phil says it is not difficult and if you look at the first post there are very detailed plans. I have now built 2. The size is such that you get two cabs from a 1220 x 2440 sheet of ply. If you only build one cab it will be expensive. The poplar ply we used was 15 mm and the cost approx £50 per cabinet or £100 for two. I am planning to build a combo version so if [size=4]we can get two other people interested, I will buy some ply and dry fit the cabinets, cut the holes and then send them out to you for easy assembly. That means just [/size]glueing [size=4] [/size]and[size=4] screwing the [/size]cabinets[size=4] together[/size]

[quote name='molan' timestamp='1495990046' post='3307973'] One thing to think about in the pairing you're suggesting is the porting. The HR 4x10 is rear ported whilst your HF210 is front. This tends to mean that the 210 is going to be a bit more dominant in the stage sound than the 410. I've tried this with Bergantino cabs and the newer front ported ones were significantly louder up close than the rear ported ones. There is an HF410 that might match the 210 a bit better - depends on the tone and stage sound you're after of course. It could be that the 210 will be the clarity for onstage monitoring whilst the 410 will be the 'big thumper' to spread around the stage and out into the audience. [/quote]If the Bergs use the same drivers, and are tuned to the same frequency and are the same volume, at the place were you were standing, you may be correct. If any one of those parameters or the power supplied to the speakers is different, then you may be mistaken.

I looked at the 407N as it is a lot lighter but the response at the low end is not as good as the 407 ferrite it would have needed a crossover frequency above 2KHz.

[quote name='FinnDave' timestamp='1495459795' post='3303872'] In the 120 plus gigs I've played with The Wirebirds, I doubt that more than 10% have had the bass through the PA. Apart from vocals, the only thing we mic up is usually the bass drum. Only when we play a festival or bike rally (and not always, even then) do we have the benefit of a big PA and sound crew. [/quote]+!

Well another trip over to Casterbridge (Dorchester) Stevie and I (well Stevie really) compared my cab, fitted with the Beyma SM212, Celestion Compression attached to a P Audio horn with the Prototype MK2 cabinet fitted with an Eminence Kappalite 3012LF and a Celestion 6" mid range driver. Firstly we put some recorded bass guitar through both cabinets. We were both surprised how different they sounded. Initially the impression was that the Kappalite went a bit lower and the SM212 went a bit higher. However you cannot trust your ears. When we measured the response, the low end was very similar. At the lower end around 50Hz there was very little in it but the 3012LF had a tad more low end but not much. However the mids showed a dip in the response of the 3012LF of around 2dB from 150Hz . So our ears interpreted the lack of mids as more prominent bass. For bass guitar both were excellent, although with music through them the SM212 plus Celestion Comp driver was superb. It's measured response would shame most hifi speakers being fairly flat from about 55Hz to 20KHz. Of course the Kappalite is well over 1Kg lighter than the Beyma so all things being equal the cabinet will also be lighter. It will also handle more power than the Beyma although how much louder it can go is debatable. I was persuaded to build the Mk2 after hearing a full range 12" cabinet of Stevie's that had a Deltalite (I think) in it. Whilst the Deltalite cab did not go as low as either of those tested today, it proved, along with the BC 1x12 MK1 that a single 12 can make a great bass cabinet. Stevie was going to build a 3 way speaker and he told me he did prototype it before building the 12/6 but as the placement of the drivers was determined by the dimensions of the baffle, it was far from ideal and sounded no better or maybe worse than two way the 12" plus horn I built. I should add the caveat that today's lesson is that you cannot design a cab on paper and you can only compare cabs when A/B ing them. One of the best things about this whole process is that I have learnt a lot about speaker design. Having the measuring gear at Stevie's meant we could check our ideas and those of others and prove, or disprove, theories and ideas. The basic idea of a low cost relatively light weight cabinet has been achieved even if the cost was higher than I imagined. The cost? About £250-£300 for the materials for mine. The weight? 15.3Kg (34lbs). The next test is Saturday when it will have a 250W amp driving it at a gig.

[quote name='Passinwind' timestamp='1494471460' post='3296265'] FWIW, I've gone as low as 18K on some of my amps and preamps. My passive/high impedance inputs are usually at around 270-330K or so, but they are really just meant as a courtesy for guest players at open mikes and the like. My preamps can make crazy high end up into the ultrasonic range quite gracefully, and a higher input impedance tends to necessitate reining that in, which I prefer to avoid given my own wants and needs. My workaround for unbuffered piezo pickups and the like is to insert an active DI/buffer box inline with the active input. I've also been playing around with discrete FET preamps lately (Tillman/Kruetzer style), and I could see adding one of those boards working well for John if he needs a higher impedance and or a little more gain at the front end. Tradeoffs, always tradeoffs. [/quote]Well I have three basses, one, my Greg Bennet, is active. The other two are a passive, a Fender Aerodyne Jazz and a Peavey Milestone (V )P type). I will be putting a Musician 2 band in the Peavey at some point and the Fender is about to get new pots, probably followed by a buffer although that might change if I decide I am good at routing. The idea behind the new pots for the Fender is that even with the J pickup fully off, there is still some interaction with the P pickup. So I was going to put switched pots in so I can really solo the pickups. Ironically I usually use either a BDI20 or my Korg AX3000B in the front anyway so I am already buffering it.

I contacted Michael at Modulus Amplification and he can do a silve /black panel to my design. To buy more decals sheets would be at least £10, you need lots of spares as I, at least, never get it right first time. For £22 from Modulus I get a properly produced front panel. I am really happy with the design except for a few things. The switch next to the input jack will go. It is too close to the jack and might get knocked and damaged. I will put two sockets, one high impedance for passives and one lower impedance for actives, as on passinwind's original design. Charlie only plays active basses. There is an argument that the lower impedance works well for passive basses too. Having the option will mean I can test that theory for myself and it may reduce induced noise. The switched mids was not on Charlie's original design, that was 450 Hz fixed, but I love the Mid on my old HH amps at 650Hz so I put a switch in so I could choose. The original design also had the capability of a bright switch but, like Charlie, I have decided not to implement that. I have also wrongly labelled the EQ and PEQ switches. They are PEQ and HPF on and off, the normal EQ section is in all the time. The switch on the far right is a MUTE switch but I may or may not include that. Power on the right is for an RGB LED. If I include the mute then the colour will change if muted. Blue for on, Red for mute. I will make all these taxing decisions after a pint of Ringwood beer. More later.

Ok latest front panel mock up almost ready for wiring. It does not look too bad except some pf the decals are slightly off centre and some off the pots need their location tags removed and the shafts cut to size.

Well I was not happy with the last look so i stripped it, sprayed it Silver and tried again. It is still not perfect but I will use it as is to complete the wiring and if I cannot live with it, will do as passinwind suggested and use Front Panel software from [url="https://www.schaeffer-ag.de/en/downloads/front_panel_designer/?no_cache=1"]Schaefer[/url]. Current estimate is about £40 for a really professional front panel but if the amps is as good as I hope, it will be worth it. The alternative is to go for an engraved panel from [url="http://modulusamplification.com/CUSTOM_FACEPLATES-W3.aspx"]Modulus[/url]. So on to wiring! Incidentally the empty holes are from left to right, High/Low switch, Input jack, and Mute.

[quote name='Beer of the Bass' timestamp='1494253444' post='3294352'] That panel does look quite good for decal paper. I've been using it on various things myself, and the results are rarely entirely perfect. I've found it likes to creep when coated over, and my prints always seem to end up a little low-resolution looking, but I'm not computer savvy enough to figure out why. One thing I do quite like the look of is to apply clear decal paper to the reverse side of 1mm clear polycarbonate and use it as an overlay, rather than applying directly to the metal panel. I would be able to get access to a laser cutter, but I've never got around to sorting out my graphics skills well enough to figure it out properly. [/quote]Applying to the rear of acrylic or polycarbonate sheet in reverse is probably the best idea. That or an engraved panel may be my best step but I am trying one more thing tonight before I give up. More later. As for they graphics, all done on the free drawing package in Open Office or Libre Office. Oh and I do have a Laser printer but only a cheap Samsung one. One more thing. Even the good decal paper is very fiddly. I found when I did the back panel that it was best to cut the decals into the smallest size possible. Much easier to handle.

Well the new cheaper decal papers from Amazon were awful. I have done a front panel with the white decal paper I have. There are some positional errors but it does not look too bad. [size=4]I am going to wire everything up, and test then finish the front panel after. I might still go for an engraved one. here is a mock up with [/size]the[size=4] knobs just resting on top,[/size] [size=4][/size] [size=4] [/size]

Charlie I will build one of your outboards once the Amp is finished.

What a nice bloke. Sold Mick my TC BC212 and he was a pleasure to deal with. Communication was only hampered as I had lost my voice. Happy to recommend Mick to anyone .

I just use the contact details from the website. They have always been helpful.

The others are right about the impedances. The MA100 or MA150 are as you say PA amps that have a simple two was baxandall EQ system but are also designed as mic inputs they won't be ideal for bass.

[quote name='Phil Starr' timestamp='1493279135' post='3287027'] Hi Charlie, loving your amp designs and can't wait to hear John's (chienmortbb) combo when it's finished. [/quote] A combo is my next project Phil, the current one is a 500 Watt head.

This build is still ongoing. I have been toying with different front panel ideas and decided to stick with the water slide decals I used for the back panel. The front panel is now drilled and sprayed silver. ( pics to follow). I had only one sheet of clear decal paper left and so really made sure everything was right. Put it into the slot for thicker paper and turned to the PC to select print. I thought I heard the printer start to take the paper through and tried to pull it out. MISTAKE. The paper creased and that caused a paper jam. My last sheet ruined. So I have ordered another 5 sheets and hope to have the panel finished next week As with the 1x12 cab build, I have deadline, my next gig is May 13th so you should see progress here's soon.

Date in the diary.

[quote name='TheGreek' timestamp='1493291184' post='3287166'] Do you know that in 4.5 years as a member here John has never bought or sold anything? Bit of a slacker I'd say, especially as he makes dealing with him so easy, needs to be trading far more. I bought a 2x12 cab from him, deal done over the phone without any issues and the cab arrived safe and sound. Couldn't ask for a better deal. Top fella, expect trouble free trading. Hope your cold/flu/bug goes away soon.... [/quote]Going for an ENT appointment this afternoon, fingers crossed. thanks for the feedback.

My old Mag 300 was Chinese but spoke fluent bass, never let me down, even without the alcohol.

[quote name='BigRedX' timestamp='1493143431' post='3286038'] Another meaningless statistic. Are those figures average or peak level? And do they take into account the duration of the sound? [/quote]Why is it meaningless?

I played through the Rumble at a Blues Jam on Weds and without being rude, it did not sell itself to me. Of course I could not try to dial in my preferred tone but it seemed to lack any mids. Of course the host bassist may like that sound so I would not discount it completely.

It is great that you can A/B them. What don't you like about the Fender Pre-amps? Or rather what is different? I plan to put a Class D amp in my HH alongside the Bipolar Class A/B power amp. I will have a have a switch (or two) so that I can change from one to the other. Sorry to go off topic.

I think you may have hit the nail firmly on the head there. I have been working on an Ashdown MiBass 220 And it is a nicely designed pre-amp that is let down by using cheap opamps. The extra cost of decent ones is quite low, it would put the cost up by about £1.50. (TL072 if anyone is interested). I suspected that the opamps used in the Mesa are no better.