What to do with Altec 515b and 288-8g on 805b horns

[eestrera]

Hello Earl and welcome.
I'm no expert but have s similar set of drivers and use them in an A-5 configuration, with readily available (epay, CL, Kijiji) 828/825 cabinets.
The impedance differences could be addressed by swapping out voice coils in the HF units to match those of the woofs, or by bi-amping into an electronic (active) crossover.
Series or parallel resistors of the appropriate value coukld be placed around/in-line with the 16-ohm units so the amp "sees" equal nominal impedances on each driver if still using a passive network.
Others may jump in here to correct me or offer more specifics, but I have a good sounding setup of A-5's with 515-8G's, 288-8L's, and 1005B horns, through N-1285 networks. Sounded really nice this Wednesday afternoon past at my clinic's summer BBQ at my place. Low volumes but effortlessly portrayed outdoor musical imagery from 200 feet away.
Jon Archibald
Ontario, canada

Thank you for the warm welcome and thanks for the tips. Just some q's sir, . I wanted to keep the drivers as original as possible, (Im a nostalgia freak and love vintage audio) would swapping the voice coils in the HF driver change the original t/s parameters? The active crossover looks like a better alternative for me but am open to options.
The series and parallel transistors also seem to be less intrusive.

Do you have a photo of your current A5 setup? Would love to see it.

Btw, I've read that these drivers can be powered by flea powered tube amps, do you think its possible to run them via triapath t-amps?

Thanks,
Earl

[Panomaniac]

Welcome to the forum!

I also run the A5 - but have 8 ohm woofers and 16 ohm drivers on the 803 horns.
But that is not a problem, as long as you are building your own crossover. If you are trying to use an already built crossover, it would be a problem. Look at the Hiraga crossover for the A5. Use the 8 ohm section for your horns, the 16 ohm section for the woofers. You will have to adjust the resistors on the horn, but we can help with that.

Yes, you can run these with a T-amp. I have quite a collection here and they all do well.
I am the t-amp guru, after all.

[eestrera]

Welcome to the forum!

I also run the A5 - but have 8 ohm woofers and 16 ohm drivers on the 803 horns.
But that is not a problem, as long as you are building your own crossover. If you are trying to use an already built crossover, it would be a problem. Look at the Hiraga crossover for the A5. Use the 8 ohm section for your horns, the 16 ohm section for the woofers. You will have to adjust the resistors on the horn, but we can help with that.

Yes, you can run these with a T-amp. I have quite a collection here and they all do well.
I am the t-amp guru, after all.

Thanks for the warm welcome. In your A5 configuration, is that an active crossover? I've managed to download the Hiraga crossover plan and I'm still trying to undertand it. It has a design for the 8 ohm crossover and the 16 ohm crossover, so do i use the 16 ohm design for the 515 and the 8 ohm design on the 288's? Will both crossover get linked to each other in one way or another or do the go to separate amplifiers respectively? And what kind of adjustment do you do with the resistors sir? Sorry having so many questions, still trying to understand.

Would you mind sharing what t-amps your using sir and how you use them on the altecs? I'd be very interested to know. For testing if the drivers work, i just used a pair of the original sonic impact 2 amp recased and reconfigured with new output transformers and caps. Somehow I always felt safe using this low powered tripath amplifiers is testing drivers compared to my solid states. Was planning on ordering a pair of some Dayton t-amps over parts express and experiment on using them as a 2nd setup to run the Altecs. The pop pulse is also readily available in my area though I haven't auditioned one yet.

Thanks.

Regards,

Earl

[Panomaniac]

Hi Earl, glad to help. And it is a subject that I know something about!

I was using an active crossover, but now am running passive and prefer it for many reasons, not the least of which is ease of use.

The passive crossover comes after the amp, so you need only one amp. The 2 parts will be link together, but they don't really work together, that's why you can mix and match. I'll look at the design again, but I think you need only change 1 resistor value. Might put a variable resistor in there to "tune" it. That would allow you to bring the level of the horn up or down to fit your room. The crossovers will not be cheap to build, inductors are expensive, but it will serve you for years and will sound great.

As for T-amps, I have too many. Sonic impact 1 & 2, Super-T, Fenice, Virtue Audio 1 & 2, Pop Pulse, 41Hz, Sure, Trends, various Chinese, etc. They all work fine with the A5.
One problem you will have is the 16 ohm woofer. It requires a higher voltage to get 1 watt than an 8 ohm woofer. And many of the T-amps are voltage limited as they run from 12V. That will limit your peak power a bit. Like 6.5 watts peak. But that would be rather loud with the 515 anyway!

[eestrera]

What do you guys think about using the 816 enclosure for the 515b?
This one is from simplex audio. With nice wooden horns too.

[Panomaniac]

I don't think you'll get much bass out of it. The 515s need a big box.
But someone here should have experience with this combo and will chime in.

[analog addict]

It's my understanding that 60-70Hz is about the best you'll see from this combo. I have a set of 515-16GHP in 816VI's. They are essentially a sound reinforcement system from a school auditorium. Great for vocals and PA system material, not so good for bass.

A sub woofer is recommended for audio applications.