Dared MP-7 Output Impedence and 15 ohms' speakers

OK, apparently I can - but when parallel wiring to reduce 16ohms speakers to 8, will doing it twice so to speak (as there is a positive and negative cable coming from each amp tap) thus 4 in total mean the final impedence will in fact be 4 ohms as opposed to 8?
The only parallel speaker wiring diagrams I've seen show two wires one pos and one neg.

Haw many speaker systems do you have? Just what are you intending to wire in parallel?

I'd hook one speaker system to the 8-Ohm tap of each amp and listen. Unless the speakers are REALLY sensitive, you won't get much volume with 6 watts.

One tube amp two speakers both 16 0hms but the amp only has a 4 and a 8 ohm tap; I dont want to lose the power from the amp so thogoght parallel wiring would work to reduce the impedence of the speakers from 16 to 8 ohms.

But the configuration will always be two speaker cables coming from the amp to the speakers each of course having two wires; thus will the positive to positive parallel crossover connection from speaker to speaker have to be done twice? All diagrams I've seen only have two single wires.

I still don't understand. Does 'one tube amp' mean one single-channel amp? Or is it a stereo amp? Are you intending to build a 2-channel system or a single-channel system? If stereo, do you have 4 speaker systems?

Dear Toobie_noobie:

1) If you have 16 Ohm speaker, that means the internal impedence of the speaker is 16 Ohm. Any external "config wire" cannot change this though. If you want to parallel with another 16 Ohm speak then you will get effective 8 Ohm, but you end up with two speakers per channel that needs more power from your amp.
2) I assume that you have a pair of bi-wired cables so you can parallel connect to two speakers per channel. But if you connect to single speaker per channel, you still get 16 Ohm per channel.

Hope this is helpful.

Best Regards,

Joe

Cheers Joe, I never allowed for the bi-wire factor.

Jeffrey, it is a DARED MP-7 Stereo tube amp - a SET. (2 times 6 watts). They are advertised on this site with full specification.

In retrospect, I should have entitled the thread: "How do I make parallel connections to a pair of speakers from a stereo tube amp".

I have a "pair" of stereo speakers both of which have 15 ohms (16 for this purpose)impedence. As my amp taps are 4 and 8 respectively, I'll use the 8 ohm tap. Thus my goal is to reduce the impedence of the speakers from 16 to 8 ohms.

I intend to run these in parallel to reduce impedence to 8 ohms to get full "bandwidth" so to speak, best use of the amplifier's available power rather than it running out of gas after the first watt or so. Or not being able to drive the speakers efficiently if you prefer.

I have no idea however what the sensitivity of the speaker's are: being c.1960, I guesstimate they have relatively high sensitivity of 90 to 92 dB as they were (again I'm guessing) made for the then available 20 and 30 watt tube amps.

The conclusion I am trying to arrive at - is in fact very direct - thus: 'because it is a pair of speakers and a stereo amp do I therefore wire them as per any amount of parallel diagrams suggest one does on the internet, but do so - as it were - doubling up the cabling. ie two speaker to speaker connections adjoined? As opposed to the two single speaker wire connection with one adjoining cable between speakers which I adduce is merely a mono[?] set up?

I think by Joe's answer it must be yes; however the concept of biwirng the speakers to the amp - in parallel - is not something I understand and confuses me again yet further.

Perhaps Joe you could explain how I might do this. Or if anyone has a diagram even better.

Thanks for your time, I appreciate your assistance

As an addendum...

Does merely biwiring two stereo speakers result in halving the impedence - 16 to 8ohms?

Can biwirng be achieved if each speaker only has two binding posts -/+ ?

thanks

OK, Toobie, I think I've got it. The reason it took so long is that you're talking about paralleling speakers, but you don't have enough of them.

Let's talk about the left channel. You have one amplifier channel and one speaker system. What's to wire in parallel? Asked another way, what do you have 2 of to wire in parallel? If you had FOUR speaker systems, you could run a pair in parallel per channel.

FORGET about all this. You have VERY limited power and NO 16-Ohm output tap from the transformer. Just connect the speakers to the 8-Ohm taps and hope for the best. If the system isn't loud enough, buy LOTS-more efficient speakers or LOTS-more-powerful amps.

And ignore all the gobblygook about biwiring. Biwiring speakers has nothing to do with wiring systems in parallel the way you seem to want to. (Of course, biwired speaker systems do have the 2 sections driven in parallel from one pair of amp taps, but that has nothing to do with impedance.)

To answer your last 2 questions, no and no. If you want to biwire a speaker system with only one pair of input terminals, you'll have to rewire the crossover to separate the 2 sections so each can be driven separately. 'Biwiring' has to do with separation by frequency bands.
.

Thanks