what's the best way to run 2 810's and a vintage SVT?

[ampegfuzz]

I searched around didn't find an answer. I have two ampeg 810's and a 1973 SVT. What is the best way to run both, Daisy chain?

[anonymous02282011]

Each of those cabs are 4ohms.

Thus, one should be connected to the main speaker output

and the other should be connected to the Ext. Speaker output.

The reason is two-fold:

1. Each output of the SVT is 4ohm.

2. If you daisy chain them and for some reason the speakers get disconnected from the head, you would be running the SVT with no speaker load. This would be very bad for the head.

You could technically daisy chain the cabs off the main speaker output, giving you a 2ohm load. The SVT can handle that, but each output is optimized for 4ohms.

[JimmyM]

Originally Posted by adbass

Each of those cabs are 4ohms.

Thus, one should be connected to the main speaker output

and the other should be connected to the Ext. Speaker output.

The reason is two-fold:

1. Each output of the SVT is 4ohm.

2. If you daisy chain them and for some reason the speakers get disconnected from the head, you would be running the SVT with no speaker load. This would be very bad for the head.

You could technically daisy chain the cabs off the main speaker output, giving you a 2ohm load. The SVT can handle that, but each output is optimized for 4ohms.

right, although #2 is kind of a nebulous reason for not daisy chaining

if you had two 8 ohm cabs, you would have to daisy chain them into a vintage svt's single speaker out, but with two 4 ohm 810's, the transformer likes to see both speaker outs used.

[sandman51]

I've been running two 8 ohm Aguilar GS 410 cabs out of a 1975 SVT head using both of the speaker output jacks, not daisy-chained, with no ill effects.

[JimmyM]

Originally Posted by sandman51

I've been running two 8 ohm Aguilar GS 410 cabs out of a 1975 SVT head using both of the speaker output jacks, not daisy-chained, with no ill effects.

there's disagreement on whether it really hurts tube amps to run at impedances higher or lower than their ot taps. but with a vintage svt, i would always err on the side of caution.

[okcrum]

I checked the schematic, and the main speaker out on the older SVTs is from the 4 ohm tap, but plugging the second cab into the external speaker out will switch both outputs to the 2 ohm tap, matching the 2 4 ohm cabs in parallel.

[fu22ba55]

Originally Posted by okcrum

I believe the main speaker out on the older SVTs is from the 4 ohm tap, but plugging the second cab into the external speaker out will switch both outputs to the 2 ohm tap, matching the 2 4 ohm cabs in parallel.

+1

This is my understanding as well.

I called SLM in the 90's to ask the same question about my '76, and that was their response.

My amp techs have since confirmed this.

One fridge in "Speaker Out" (4 ohm) and one fridge in "Ext Speaker" switches to the 2 Ohm tap.

I've run mine for hundreds of hours this way with no issues (other than hearing loss).

Go forth and rock the earth with fuzz.

[sandman51]

Originally Posted by JimmyM

there's disagreement on whether it really hurts tube amps to run at impedances higher or lower than their ot taps. but with a vintage svt, i would always err on the side of caution.

Thanks, JimmyM, I guess I've been lucky so far....time to rethink my options.

[johnk_10]

the schematic shows the output tranny taps. it is designed to run one 4 ohm cab into each speaker output. here's the poweramp schematic for the early ones with the xlr main output:



and here's the one (1975) with the two 1/4" output jacks:




if i were running two 8 ohm cabs, i'd definitely go into one cab, and out of that cab into the other and just use the single 4 ohm output.

[Sartori]

Didn't old 810's only have one jack, anyway?

[johnk_10]

Originally Posted by Sartori

Didn't old 810's only have one jack, anyway?

yep.

[ampegfuzz]

Well one cab to each speaker out it is then.

Your Reward........ AMPEG PORN

[D.M.N.]

Originally Posted by ampegfuzz

I have two ampeg 810's and a 1973 SVT. What is the best way to run both

Loudly. Horrifically loudly.

[Travis_Bass]

mmpmpmpmmmhmm!!!! Aww thanks, now I have to do laundry Nice rig dude.

[ampegfuzz]

MORE PORN (because like people would want less porn)



BTW just hooked it up and it sounds awesome

2 things though,

1. I dated the cab and the oldest it can be is 1996 and its made of osb.
2. It sounds louder the my 2001 cab

BUt it still crushes and sounds killer

[fu22ba55]

Originally Posted by ampegfuzz

Your Reward........ AMPEG PORN

Your reward:

The appreciation of every drummer you play with from now on, and the disdain of every sound man you cross paths with.

[JimmyM]

Originally Posted by fu22ba55

Your reward:

The appreciation of every drummer you play with from now on, and the disdain of every sound man you cross paths with.

that would be good enough for me!

[johnk_10]

here's a little ampeg porn of my own :

[coreyfyfe]

Originally Posted by johnk_10

here's a little ampeg porn of my own :

Man I love this picture...

[ampegfuzz]

I have always wanted to say john, if you ever want to adopt I'm totally already housebroken!........ and only one 810? . I totally want to recover these with blue cloth now and make new frames like fu22ba55 did with his V9 cab.