Ohms

[BassmanPaul]

He traded the 8 ohm drivers for 16 ohm drivers so this configuration will yield 8 ohms. With eight 16 ohm speakers he has to choose between 8 and 2 ohms total load.

He did? I missed that! All that typing and thinking for naught!!

 

[Rick James]

Same here. OP, you're screwed. Make it a learning lesson. To paraphrase Davy Crockett, be always sure you're right, only then go ahead.

 

[Wasnex]

But I have 8 spks. in the SVT and need the whole thing to end up at 4ohms if possible.

Are 7 of your original speakers still good? If yes, which brand and model?

IHMO here are some possible solutions.
1. Get the bad speaker reconed.
2. Buy two new 32 ohm speakers that are designed for a sealed enclosure and replace both speakers in the section that had the bad driver. This will leave you with a spare original driver. Several people have used the Jensen Mods to get a bit more highs from the top chamber. Probably not the best choice if you are hitting the cabinet with big power as it is a 50 watt driver. Eminence offers the following 32 ohm drivers for sealed applications: Legend B810 (150 watts), Legend CA10-32 (175 watts), and Basslite SC10-32 (300 watts).
2a. Maybe someone can model a pair of the Basslites in the cabinet. It might work to connect a pair of 8 ohm Basslites in series for 16 ohms. Then connect the 16 ohm section in parallel with the other speakers.
3. Buy eight 32 ohm speakers that are designed for a sealed enclosure.
4. Buy eight 8 ohm speakers that are designed for a sealed enclosure.

 

[Wasnex]

He did? I missed that! All that typing and thinking for naught!!

Same here. OP, you're screwed. Make it a learning lesson. To paraphrase Davy Crockett, be always sure you're right, only then go ahead.

I reread the post. Apparently he still has the 8 ohm Neo Basslites (S2010?), and also bought a set of SC10-16.

 

[BassmanPaul]

I reread the post. Apparently he still has the 8 ohm Neo Basslites (C2010?), and also bought a set of SC10-16.

This being true, if he wants a 4Ω cabinet he MUST use the 8Ω drivers. As you said above, the 16Ω drivers limits his choices to 8Ω series parallel or 2Ω all parallel.

 

[GreyBeard]

8 8ohm speakers in parallel makes 1 ohm. Not quite a dead short but close and will fry any amp you are likely to find. Series parallel will give you 4 ohms which most amps are fine with.

 

[BassmanPaul]

8 8ohm speakers in parallel makes 1 ohm. Not quite a dead short but close and will fry any amp you are likely to find. Series parallel will give you 4 ohms which most amps are fine with.

This was mentioned a couple o’ times earlier in the thread.

 

[GreyBeard]

This was mentioned a couple o’ times earlier in the thread.

Sorry, did offend someone?

 

[glenn joyner]

I believe SVT 810s use eight 32 ohm speakers wired in parallel. 32/8 = 4 ohms. If you have a bad driver, I would either have it reconed, or replace a pair with a reasonably compatible pair of 32 ohm speakers.

If you want to replace all with 8 ohm speakers you will need to use a series/parallel or a parallel/series wiring scheme. You need to choose speakers that are compatible with the volume of the cabinet.

If you wire four 8 ohm speakers in a parallel/series configuration or series/parallel configuration you get an 8 ohm load.

Compare series/parallel with parallel/series.
View attachment 2919509

Parallel/Series
Connect two speakers in parallel: 8/2 = 4 ohms. Connect the other two speakers in parallel, so you have two 4 ohm circuits. Connect both sets of parallel speakers in series 4*2 = 8 ohms.

Series/Parallel
Connect two speakers in series: 8*2 = 16 ohms. Connect the other two speakers in series, so you have two 16 ohm circuits. Connect both sets of series speakers in parallel 16/2 = 8 ohms.

Here's another example of series/parallel wiring.
View attachment 2919494

As you can see the wiring gets pretty complicated. Connect two of these 8 ohm circuits in parallel and you are back to the cabinet's original 4 ohm load.

So wiring two sets of 4, 8 ohm spks like this will give me the 4 ohms I need?

 

[glenn joyner]

No ,my head is a Peavey 450 W Tour Series, not tube. But it is 4 ohms, thats what Im trying to get to . I already have a set of 8-4ohm spks and a set of 8-16 ohm spks, I know NOW, that I should have bought 32 ohms, but I didnt know. Thank you all for your help. Thanks Wasnex, I will try what you said.

 

[Rick James]

my head is a Peavey 450 W Tour Series... it is 4 ohms

No, it's not. It has a 4 ohm minimum load. That's the lowest you can use, but 8 ohms is just fine. Whatever you do don't mix different drivers, and anticipating that old cherry 'but I want to get all the watts out of my amp so I have to have a 4 ohm cab', you don't.

 

[Wasnex]

So wiring two sets of 4, 8 ohm spks like this will give me the 4 ohms I need?

Two 8 ohm speakers in series gives 2x8=16 ohms. Four circuits of 16 ohms in parallel gives 16/4= 4 ohms.

Assuming your Neo Basslite is the S2010, I would model this in the cabinet before going through the trouble of installing and totally rewiring everything. The threads I have seen on the subject, suggest the S2010 will work in a sealed cabinet but the lows will be a bit thin.

You might be better off with eight SC10-16 wired for 8 ohms. It would be best to model both drivers in the cab before going further.


FYI the Tour Series 450 makes 300 watts at 8 ohms and 450 watts at 4 ohms. The power differential represents about a 1.8db difference in volume.

 

[BassmanPaul]

Sorry, did offend someone?

Nah! Just keeping the ducks in a row is all!

 

[glenn joyner]

Two 8 ohm speakers in series gives 2x8=16 ohms. Four circuits of 16 ohms in parallel gives 16/4= 4 ohms.

Assuming your Neo Basslite is the S2010, I would model this in the cabinet before going through the trouble of installing and totally rewiring everything. The threads I have seen on the subject, suggest the S2010 will work in a sealed cabinet but the lows will be a bit thin.

You might be better off with eight SC10-16 wired for 8 ohms. It would be best to model both drivers in the cab before going further.


FYI the Tour Series 450 makes 300 watts at 8 ohms and 450 watts at 4 ohms. The power differential represents about a 1.8db difference in volume.

Wasnex,I dont have any 8 ohm spks. I have 8- S2010 at 4 ohms and 8-SC10 at16 ohm..The 8-30watt ,32 ohm spks that came out of the cabinet is only 240 watts total. Not enough without two cabs. I have other 15 ' spks in other cabs but I am trying to get this Ampeg cab going again. All original spkrs from it are here and working but make noise when I play it. Like maybe over driving them. Two were reconed after it fell over in transit, that's when the noise started. Thats why I'm trying to put more wattage spks in it that match my head. Can I get 4 ohms from these 16 ohm spks or do I have to go with 8 ohms like you mentioned?

 

[Wasnex]

Wasnex,I dont have any 8 ohm spks. I have 8- S2010 at 4 ohms and 8-SC10 at16 ohm..The 8-30watt ,32 ohm spks that came out of the cabinet is only 240 watts total. Not enough without two cabs. I have other 15 ' spks in other cabs but I am trying to get this Ampeg cab going again. All original spkrs from it are here and working but make noise when I play it. Like maybe over driving them. Two were reconed after it fell over in transit, that's when the noise started. Thats why I'm trying to put more wattage spks in it that match my head. Can I get 4 ohms from these 16 ohm spks or do I have to go with 8 ohms like you mentioned?

Sorry I misread and thought you had some 8 ohm speakers. With 4 and 16 ohm speakers your stuck with 8 or 2 ohms.

IMHO your best bet would be the SC10s hooked up for 8 ohms. Configuring the 4 ohm S2010s for 8 ohms would involve putting more speaker in series. I am not an expert, but I believe there are problems with running multiple speakers in series: 1. If one of the speakers in series stops working, they all stop working (this is a fact), 2. I believe multiple speaker in series also impacts damping and possibly frequency response (I don't know if this is a fact or urban legend).

I really wish there was some way you could trade 8 of your drivers for one of the three Eminence 32 ohm options that is designed for this cabinet.

 

[glenn joyner]

Wasnex, so do I ,but I got these 16 ohm spks from Parts Express and they have a policy they can only take back anything up to 45 days. Well I had to order them two at a time,so they would only take back two of them. That didnt help anything. Lol. These spks have never been opened and the tape on the boxes has never been moved! And the 4 ohms I got from Speaker Addict but I had installed them so they wouldnt take them back. Would it be worth it to order the SC 10-32 ohms and just try to sell these others? Or just go with making 8ohms and be satisfied?

 

[Wasnex]

Wasnex, so do I ,but I got these 16 ohm spks from Parts Express and they have a policy they can only take back anything up to 45 days. Well I had to order them two at a time,so they would only take back two of them. That didnt help anything. Lol. These spks have never been opened and the tape on the boxes has never been moved! And the 4 ohms I got from Speaker Addict but I had installed them so they wouldnt take them back. Would it be worth it to order the SC 10-32 ohms and just try to sell these others? Or just go with making 8ohms and be satisfied?

Depends, how much more money are you willing to lose for 1.7db difference in SPL. How much can you sell the drivers you have for and how much will it cost to buy the SC10-32. I believe that is your bottom line.

If you go with the 8 ohm option, please clearly label the input with the new impedance.

Are you sure your S2010s are 4 ohms? Eminence does not list a 4 ohm option for this speaker. Speaker Detail | Eminence Speaker

 

[glenn joyner]

Depends, how much more money are you willing to lose for 1.7db difference in SPL. How much can you sell the drivers you have for and how much will it cost to buy the SC10-32. I believe that is your bottom line.

If you go with the 8 ohm option, please clearly label the input with the new impedance.

Are you sure your S2010s are 4 ohms? Eminence does not list a 4 ohm option for this speaker. Speaker Detail | Eminence Speaker

Yes, but not

Depends, how much more money are you willing to lose for 1.7db difference in SPL. How much can you sell the drivers you have for and how much will it cost to buy the SC10-32. I believe that is your bottom line.

If you go with the 8 ohm option, please clearly label the input with the new impedance.

Are you sure your S2010s are 4 ohms? Eminence does not list a 4 ohm option for this speaker. Speaker Detail | Eminence Speaker

Yes they are 4ohms but dont know about that number, they were advertized as 10" basslite neo magnet spks. I cant find them now either ,but they came from Speaker Addict! $79 each I believe. I guess I'll just bite the bullet and buy the 32 ohms. They are $89 each, but I should have done more looking instead of buying. Lol. Thanks for your help.

 

[Wasnex]

Yes, but not

Yes they are 4ohms but dont know about that number, they were advertized as 10" basslite neo magnet spks. I cant find them now either ,but they came from Speaker Addict! $79 each I believe. I guess I'll just bite the bullet and buy the 32 ohms. They are $89 each, but I should have done more looking instead of buying. Lol. Thanks for your help.

That's really weird. Maybe they are DELTALITE® II 2510-4 or KAPPALITE™ 3010LF-4. The Kappalite appears to be discontinued.

Well you have enough speakers to make a bunch of cabinets if you like. If not, good luck selling the inventory and I hope the SC10-32 rocks your world. Post a review when the deed is done.