Finding out the power an unknown speaker can handle

[wakibaki]

I was trying not to say that

Me and my big mouth.

Obviously LoFi is not an objective only to be derided, for many years people found it preferable to NoFi, it's just that you should know the reality.

I've been delighted that many of the things I've built in the past worked at all. If you just want to tinker around and maybe learn a bit then these are fine candidates in one sense because it doesn't matter if you destroy them.

w

 

[planet10]

Where's P10 Dave?

Those are a favorite for the vintage OB crowd... not as good as the alnico version, but despite the cheesy looks are quite musically satisfying... often used with a small tweeter (the 2" thimble tweeter works well)

dave

 

[NIC1138]

Hello. I'm delighted this thread got so much attention, thanks for all the comments, everybody!...

I cut off the made-in-Germany connectors and "linked" the speaker cables to a 3.5mm TRS plug using a clotespin. The output I'm using is a headphone one, and so the volume level is low, but good enough to have a taste of the boxes.

I listened to some early 1970s Canned Heat albums for a couple of hours (trying to be hi-fi, HIstory FIdelity), and liked what I heard. The bass was better than I expected --- I am used to these small oval TV and computer 0.25W speakers. I believe a tweeter can in fact make a difference, but I can't hear much high frequencies anyway, so I am not much concerned. My own "youthful exuberance" endowed me with lo-fi ears for my later life.

Is there any modifications you think I could try to do to the cabinet? (other than destroying it ) What should I do if I decide to try getting tweeters?

I am happy to know that someone can consider these speakers low-quality. I look forward to the day I will feel these are garbage, and not only prefer to stick to hi-fi, but have it available for very low prices. I would gladly pay R$50 to get speakers this size and better than these. I am not sure I can find it, at least here in Brazil.

My uncle brought these from Europe back in the seventies to my grandfather. They knew (and I do) it wasn't hi-fi, but that's what we can afford. The alternative I have are shitty 0.25w "multimedia speakers", or a JVC portable CD player with 4 inches cones and an internal bass one.

Perhaps some of you don't share my excitement about these speakers because you live in places where it doesn't mater much if your equipment is imported from countries like Holland, but here in the "developing world" it's often a great deal.

I found the original amplifier, and I'll check its characteristics later today. The day I perform some more tests on these speakers I'll add up here. That will probably be just in one or two months...

 

[HK26147]

What should I do if I decide to try getting tweeters?

These are about the smallest tweeters I've found:

An externally hosted image should be here but it was not working when we last tested it.

They are very inexpensive and go on sale a lot.

Seems like a crafty DIYer might find a way to turn that woofer into a co-ax. Perhaps a simple frame to hold the tweeter out in front of the dust cap.

Are you tinkering or you got a goal in mind.

 

[Saturnus]

I would gladly pay R$50 to get speakers this size and better than these. I am not sure I can find it, at least here in Brazil.

50 Brazillian Real is about USD 25 ... I'm almost positive you can find something much better for that even in Brazil, although google searching in english only turns up super pricey golf drivers for me, you should have better luck in potuguese.

 

[NIC1138]

Prices of acceptable speakers in Brazil

50 Brazillian Real is about USD 25 ... I'm almost positive you can find something much better for that even in Brazil, although google searching in english only turns up super pricey golf drivers for me, you should have better luck in potuguese.

If you are curious, here are some links in the local e-bay for speakers that might be closer to what the hi-fi crowd find more aesthetically and technically good-looking.

R$110 (€35)
http://produto.mercadolivre.com.br/...stica-acabamento-de-primeira-philips-unid-_JM

R$149 (€47)
http://produto.mercadolivre.com.br/...-philips-acusticas-system-250rms-3500pmpo-_JM

R$179 (€57.30) (non-Philips for a change)
http://produto.mercadolivre.com.br/MLB-87523280-par-de-caixas-surround-aiwa-sx-r220-50w-_JM

This one is interesting. Brazilian "professional" brand, Staner http://www.staner.com/
This is not their smallest speaker, but is still quite expansive. A single one for R$320 (€102)
http://produto.mercadolivre.com.br/MLB-83020636-caixa-acustica-staner-la-90-_JM

To finish, a very inexpensive but suspicious-looking stereo set by CCE, Brazilian "consumer" brand. R$51 (€16.3 = US$21.8)
http://produto.mercadolivre.com.br/MLB-84109601-liquidaco-par-de-caixas-cce-_JM

 

[Steerpike]

I don't think those drivers are as bad as people are suggesting. The cabinets may be less than wonderful, but those Philips full ranges sound pretty Ok if put in a solid cabinet.

I have a pair in thick wooden boxes, and driven from an EL84 single-ended valve amp, they are plenty loud enough, and sound very pleasant.

If you were close, I'd make you a good offer for them

 

[Saturnus]

Well, NIC1138 I'm talking about drivers to make DIY speakers of, not finished speakers.

 

[NIC1138]

Well, NIC1138 I'm talking about drivers to make DIY speakers of, not finished speakers.

Sorry, Saturnus. I'm not sure about how much the drivers would be, and how much would be everything. I did find some car drivers to sell here at not so terrible prices...

My expertise is more in the "high-level" areas, I have experience just on signal processing and basic electronics: designing sources and chip amps, like I did this time: http://www.diyaudio.com/forums/showthread.php?s=&threadid=101638

I hope to build a complete speaker some day, but right now I just want to pick up these speakers to which I am emotionally attached to, and build a "fair" amp for them. So I come to you, my admired speaker experts and I ask what amplifier would you guess I should build for it. (And I thank for the many nice guesses.)

I finally found the tape recorder they came with. It's a N2405, and the label under it states a power consumption level. My hypothesis of building a 14+14W amp is gone, as the whole equipment takes just 20W!... So I imagine the speakers receive in fact only 6+6W, if much. So I'll probably go for a TDA2007 chip. Later I'll do the definitive test of plugging the thing to a good amp and see how much it can take. (I hope to measure the whole transfer function so we can see its terribly high lower cut-off freq, and the miserably low higher freq limit )

To finish, here is a pic of my lo-fi adaptor