6v6

[quote name='EliasMooseblaster' timestamp='1419946738' post='2644182']
From a bit of judicious googling, I think the problem is that the output transistors have failed. Assuming that's the correct diagnosis, are these kinds of repairs likely to be
- particularly expensive?
- particularly specific (i.e., likely to depend on a tech knowing his/her way round that manufacturer's stuff)?
- something I could do myself if I can get the parts?
[/quote]

I think the answer to all those is "it depends" - replacing the output transistors isn't that hard provided you're proficient with disassembly and soldering, but you have to ask yourself why they failed, and if you have the skills/equipment to properly diagnose the root cause.

FWIW I've got a lot of experience fault finding electronics and some amp/speaker problems are just not DIY friendly (some definitely are though, it depends..).

For one of the non-DIY problems I hit recently (a Mackie active PA speaker with corrupted firmware), I used http://www.amphospital.co.uk/ who were good, although not particularly cheap.

[quote name='dincz' timestamp='1418932618' post='2635035']
Interesting. I just took a look and apparently they aren't airtight

[url="http://www.neutrik.com/en/speakon/speakon-chassis-connectors/nl4md-v-s"]http://www.neutrik.c...ctors/nl4md-v-s[/url]
[/quote]

You could just build a little box for the jack panel to fit into inside the box (obviously tweaking the rest of the dimensions slightly to maintain the same overall volume).

1 sold?!

+1 for TI flats, incredibly easy to play. Although they obviously won't do the zingy stainless rounds thing if thats what you're after, they're not at all dull and thuddy like some flats - I find them pretty versatile on a P-Bass.

This whole thread makes me kinda sad really. [size=4] [/size]

I like the idea of this cab, and I'd love to support a UK based manufacturer, but I just can't get my head around the lead times being discussed here at all.

Such a shame - I don't get why you'd do that to a bass, especially if you ever plan to sell it, but each to their own.

"[color=#282828][font=helvetica, arial, sans-serif][size=4]it's very well looked after" [/size][/font][/color]

If you're going to rout it yourself, make or buy a template. Yes it's more money or time, but freehand routing is incredibly difficult to do accurately, especially if you're not super-confident with the tool.

There are a few ways to make templates, but see [url="http://basschat.co.uk/topic/200152-1x12-diy-cab-build/page__view__findpost__p__2211141"]http://basschat.co.u...ost__p__2211141[/url] for one way I use, which is put some small battens under the ply/mdf scrap, drill through then cut inside the line with a jigsaw and use a flush-trim bit to get an accurate square template aligned with the battens.

[quote name='dannybuoy' timestamp='1415866229' post='2604530']
Finally some good news for Android, hope to see more support in future!

[url="http://liliputing.com/2014/11/now-samsung-phones-can-act-like-guitar-effects-pedals.html"]http://liliputing.co...cts-pedals.html[/url]
[/quote]

Yeah, I've been waiting for this forever, it will be interesting to see what the latency figures are like when some hands-on test reports appear.

Relatedly, anyone got any reports of how the ipad air2 works out latency wise?

It must be the cab, I use a LM3 (which AFAIK has the same power rating) into a single 1x12 and it can compete with a moderately loud drummer and two guitar amps on small stages just fine, so a 4x10 should be plenty.

Were all of the drivers in the cab actually working?

I've used bitsbox for stuff like this, so they may have an equivalent you could use:

http://www.bitsbox.co.uk/index.php?main_page=product_info&cPath=253&products_id=1912

[quote name='Ghost_Bass' timestamp='1415791729' post='2603753']
Any news on the cabs? Photos, specs, plans, etc.? I'm looking forward to have a crack at building one for myself. Do they have a name, brand? Maybe a logo contest to keep us busy
[/quote]

If you're keen to get going, you could refer to my build diary, which includes dimensions for a cab built around the same driver (Beyma SM212).

http://basschat.co.uk/topic/200152-1x12-diy-cab-build

I can't claim anything like the expertise of the folks driving this thread (I got a lot of help from Phill Starr working out my design) but I've been gigging the cab for a year and it works very well.

When I went precision shopping I tried a lot of MIM and MIA stuff, and in the end came away with a US standard.

Some of the MIM models were nice, but for me, what clinched it was the MIA was lighter, better finish, better hardware and electronics, better resonance, better neck feel and fretwork, also came with a case, lead, truss rod tool and other bits which AFAIK the MIM ones don't.

Like anything though, it's the law of diminshing returns, many of the MIM models are really good for the money, so you really have to try before you buy and get the one which feels best to you and which suits your perception of value for money.

[quote name='linear' timestamp='1415619099' post='2601962']
I'm not sure I understand. Do you mean a situation where a jack is not pushed all the way in and the tip touches the ring contact?
[/quote]

Ah, I actually misread your post, sorry - I thought you said connect the tip and ring, not ring and sleeve.

Still, I don't see much advantage, as the sleeve will contact the whole body of the jack anyway and never wears out (other than getting corroded I suppose).

IME it's normally the tip connection which gets worn first, which this doesn't really help with.

If it's a decent (genuine Switchcraft) socket it should last for years anyway, but I guess there's no harm doing what you propose, if you want to.

Sorry for the confusion!

[quote name='linear' timestamp='1415459601' post='2600590']
Yea, it's a passive bass, and I can't see any situation where I would be plugging a stereo jack into it.

I thought maybe it might increase the chances of the jack making a connection when not pushed in all the way, or when the socket's internal contacts eventually starts to lose their springiness. An unlikely speculation I guess, but I thought I should double-check.
[/quote]

If you do that, you'll short the tip to ground when you use a mono jack plug in there.

See this recent thread, there's a lot of useful info:

http://basschat.co.uk/topic/247793-help-a-newbie-with-his-speakersdrivers/

[quote name='redstriper' timestamp='1415294961' post='2598939']
Pyramid Golds might answer that problem for you
[/quote]

Oh no, I'm going to have to get some now aren't I? [size=4] [/size]

[size=4](thanks though! )[/size]

[quote name='Chienmortbb' timestamp='1415313987' post='2599228']
Just to clear things up a little, this was never meant to be a build your own bass amp thread, I was just wanting to explain the thinking behind how I am going about specing my own home brew amp. It is a learning process and I thought others could learn along with me, just as I learnt from the 1 X 12 Cab build diary. If everyone is happy with that I will continue.
[/quote]

Aww man, I feel bad now. [size=4]Apologies if my demands appear unreasonable - it wasn't my intention to derail this thread [/size] [size=4] [/size]

[size=4]H[/size][size=4]onestly, I thought my original request for details would result in a "sure, here's a link to the thread with the preamp schematic on TB", but if that's not the way this is going down, (again) fair enough.[/size]

[size=4]In my defence, I'm an engineer, and thus immediately want to discuss implementation specifics. That's my affliction though, I can't help it! [/size]

[size=4]Good luck with the build.[/size]

[quote name='LukeFRC' timestamp='1415279944' post='2598689']
equally though if I had a bill fitzmaurice cab build thread, bill himself might even join in but I dont think anyone would expect his design build plans provided for free....
[/quote]

I never said anything about free - I'm just saying that unlike the 1x12 cab build diary this is supposed to be inspired by, if the key details of build specifics are private between only two thread participants, nobody can really benefit from the experience if they want to follow a similar path.

For example, if I read a BFM build thread and like it, I can just pay Bill for his plans - I'd have no problem, for example, paying Passinwind for a PCB if his design sounds nice, but that's not what's being proposed AIUI, perhaps I am misunderstanding.

Anyway - like I said, fair enough, I'm sure the pictures, graphs and random design musings will be most informative and interesting.

I've been using the normal Fender cables (the rubbery ones with shrink-sleeve over the connectors), and for the price I think they're pretty good.

Not tried the tweed ones, personally I'd rather just have a tough rubber cable where you can easily inspect it for squashes and cuts.

I really like them, but sometimes I wish they came in different gauges so I could move up to some with the same tone and feel, but slightly more tension.

That said, I suppose the bandy feel is part of the reason they're so nice/easy to play.

[quote name='Passinwind' timestamp='1415142587' post='2597271']
I'm not planning on posting an actual schematic at this time, but I will be happy to show build pics, component details, block diagrams, performance measurements, and modeled behavior of the various bits.
[size=4][/quote][/size]

[size=4]Ok, fair enough.[/size]

[size=4]For me that devalues this thread quite a bit, because without specifics like schematics, it becomes a build commentary of an effectively private collaboration between you and [/size][size=4] Chienmortbb, rather than an actual build diary.[/size]

[size=4]That said, I'm sure the other details you mention will be interesting. [/size]

[quote name='Passinwind' timestamp='1415130435' post='2597096']
so it's not as if Chienmort will just be building up a known-good design from a blueprint, although we certainly both hope it will play out something like that. A good part of the end result will depend on his own choices and tweaks. I have tried to make my design pretty accommodating to modifications...we'll see how that goes.
[/quote]

There have been references to your design but no links, for those of us who've not followed the TB threads closely (I had a quick look a the link from post #6 but didn't spot the schematic), can you share links to the design's you're referring to and have been collaborating on?

[quote name='Kevin Dean' timestamp='1414778255' post='2593252']
The generation 3 stuff came out a week after I collected my super 12T , I was really cheesed off , & was offerd a T shirt by way of compensation .. I wish I was given a call .
Anyway the two 2 x10 looks like a good idea . If cabs were kept in stock I would have probably ordered by now & no picture doesn't Help ..& I can't stand waiting for stuff . the 12T is still a great cab after all my moaning .
[/quote]

I thought they offered a one month trial/return policy?

So, to clarify, it's pretty likely to be impossible to modify an ATX SMPS which outputs 5 and 12v to give the necessary voltage swing.

The other issue is SMPS technology is really complex, and well beyond what even pretty experienced electronics DIYers are likely to be able to modify (particularly if, as in this case, it'd effectively be redesigning the whole power supply..)

That complexity is one reason why I personally prefer simple traditional power supplies and either valve or mosfet amplifiers - it's just much more accessible to a hobbyist and if it breaks, I stand a reasonable chance of fixing it, which is unlikely to be the case with either SMPS or class D technology (not saying it can't be done, just that it's really hard for non experts without specialist equipment and knowledge)

[quote name='stevie' timestamp='1414764675' post='2593089']
True, but that's why I said 'modify' - maybe bump them up from 12V. Or maybe that's impossible. I'm just here to learn .
[/quote]

Ok, apologies, my previous response came off rather curt as I was in a hurry and didn't explain, so let me see if I can remember and explain the theory

Ultimately, the output of the amplifier consists of an AC voltage (the signal applied to the speaker), which pushes current through the speaker (current determined by the impedance, so lets say nominal 8ohms)

If, for the sake of argument, we want 300w RMS, and we assume the speaker signal to be a sine wave, this means we can apply a simplistic estimate based on ohms law:

Power = Voltage x Current (P = V x I)

Voltage = Current x Resistance (V=I x R)

So if we combine the above, P=(VxV)/R, or RMS voltage = square root of power x resistance, so sqrt(300*8), which is just under 50v RMS

we multiply by sqrt(2) to get from RMS to peak-to-peak, so you're looking at, roughly, 70v p-p swing to push 300w RMS through 8ohms.

That's my understanding of the theory anyway, if I'm remembering correctly!