Complete Altec Setup - Help Please

[Houston]

I couldn’t tell if it was for the church or for a friend at the church for personal use.

So does the OP have a single 515C and a single Hollywood 515? He mentioned the 20ohm Hollywood 515 but also shows a pic of a 515C.

I apologize. It’s not the Hollywood 515. It is the single 515c.

 

[Houston]

This would be what I would really like to land because it is what is written by Altec to be the correct design for these components.

 

[elitopus]

So you have one 515C and two 291A correct? Does the horn have a double throat or do you have two horns and one bass cabinet?

 

[Houston]

So you have one 515C and two 291A correct? Does the horn have a double throat or do you have two horns and one bass cabinet?

I have one 291a, one 515c, one bass cabinet, and one 1594b. All operational. I posted the before cabinet modification and a after modification. That probably threw you off thinking 2 in total.

 

[Houston]

I have one 291a, one 515c, one bass cabinet, and one 1594b. All operational. I posted the before cabinet modification and a after modification. That probably threw you off thinking 2 in total.

 

[Houston]

These are just images of the upgrades I did to it. I wanted to bring the the eye appeal back to life. It’s externally rhino lined. Plus that’s a sound deadening material.

 

[EarlK]

Don't buy the JBL 3115a network.

It has all the wrong Capacitor & Coil values to work properly with Altec componentry .

Either buy an Altec model of the type that I displayed or build an equivalent using parts from Parts Express.

To build a single N500F/G variant ( with variable Lpad ) here's what you need;

( these stock values are close enough to the Alec values ).

Erse 7.0 mH Coil > you'll need 2

Audyn Q4 15uF capacitor > you'll need 2

https://www.parts-express.com/dayton-audio-dmpc-22-22uf-250v-polypropylene-capacitor--027-415] Dayton 2.2 uF capacitor > you'll need just 1

https://www.parts-express.com/speaker-l-pad-attenuator-50w-mono-3-8-shaft-16-ohm--260-254] 50 Watt, 16 ohm Lpad > you'll need 1

https://www.parts-express.com/10-ohm-10w-resistor-wire-wound-5-tolerance--016-10] 10 Ohm, 10 watt, wirewound resistor > you'll need 1

Wire and other connectors I'll leave to you to source.

This can all be built on top of a 3/8" piece of plywood and then inserted inside your horn cabinet.

 

[Houston]

Don't buy the JBL 3115a network.

It has all the wrong Capacitor & Coil values to work properly with Altec componentry .

Either buy an Altec model of the type that I displayed or build an equivalent using parts from Parts Express.

To build a single N500F/G variant ( with variable Lpad ) here's what you need;

( these values are close enough to the stock Alec values ).

Erse 7.0 mH Coil > you'll need 2

Audyn Q4 15uF capacitor > you'll need 2

https://www.parts-express.com/dayton-audio-dmpc-22-22uf-250v-polypropylene-capacitor--027-415] Dayton 2.2 uF capacitor > you'll need just 1

https://www.parts-express.com/speaker-l-pad-attenuator-50w-mono-3-8-shaft-16-ohm--260-254] 50 Watt, 16 ohm Lpad > you'll need 1

https://www.parts-express.com/10-ohm-10w-resistor-wire-wound-5-tolerance--016-10] 10 Ohm, 10 watt, wirewound resistor > you'll need 1

Wire and other connectors I'll leave to you to source.

This can all be built on top of a 3/8" piece of plywood and then inserted inside your horn cabinet.

YES!!! Another very helpful piece of usable information. Thank you so much. I’ll get the n500g first since there is limited stock. Then I’ll get the other items thru parts express. I like parts express. I have issued them a lot in the past. If I do this do you this I can get this plane off the ground again?

 

[Houston]

YES!!! Another very helpful piece of usable information. Thank you so much. I’ll get the n500g first since there is limited stock. Then I’ll get the other items thru parts express. I like parts express. I have issued them a lot in the past. If I do this do you this I can get this plane off the ground again?

YES!!! Another very helpful piece of usable information. Thank you so much. I’ll get the n500g first since there is limited stock. Then I’ll get the other items thru parts express. I like parts express. I have issued them a lot in the past. If I do this do you this I can get this plane off the ground again?

No issues with parts express I mean.

 

[Houston]

No issues with parts express I mean.

Wait.... Or. is the parts express order needed if I find the n550g???

 

[Houston]

N500G. Fat fingers. I’m sorry.

 

[Houston]

Thank you Sam, Damacman, Earlk, and Bowtie. Y’all have been very kind and very helpful. Y’all be safe and bless you.

 

[Denny98501]

I ran across a complete Vintage Altec setup. I replaced the horn diaphragm, ohm’d the sub, and powered up the amp to ensure it’s operational. I Wired in a RCA female, 120 volt switched fan, built a housing for the horn to be closed in, then fixed cosmetics to existing box. The horn sounds great but the sub barely moves. Any insight would be nice. Thanks for your time.

I recently built a set of these cabinets for a pair of 15 inch 602 duplex Altecs. They sound wonderful. I would be guessing that you have a crossover issue as in you need one. The Altec HF horn is very efficient and you are sending a full load of frequencies to it for which it was never designed. It may explain why you needed to replace the horn diaphragm. I would disconnect the high frequency horn from the amplifier. You cannot hurt a woofer by feeding it high frequency signals; now see how it sounds.
If you are getting good response, you need a crossover to protect the HF driver. It can be as simple as an inline capacitor. Most of the early Altecs are very efficient and have a max power rating of 25 watts. If the LF driver still does not give much response, you may have a damaged voice coil.
With a horn loaded LF driver, there will not be much (almost none) cone excursion. Distortion comes from large cone travels. Small travel means almost no distortion. This is not a sub woofer. It does not do earthquakes. It does give very clean sound down to 50 cycles in that cabinet.

Since this is an Altec area, I will mention that the 602 is a lovely speaker. It crosses over at 3000 Hz. I tested both drivers. The 15 inch wooer goes up to 3000 Hz smoothly and the HF horn goes down to 3000 Hz smoothly. When testing, I fed one volt into each driver and they were LOUD. One volt into the HF horn is just about enough to crack the enamel off your teeth. I picked up a two way 3000 Hz crossover from Parts Express, ran a BODE plot on the oscilloscope to see if it really was as advertised (it is), and am enjoying the music.