Ashdown amp not cutting it....
 

Hi guys and girls, i have a small dilema....

I have an ashdown MAG 300 evo II head which i originally paired with the MAG 410 (350 watts - 8 ohm).

The head is rated at 307 watts RMS at 4 ohm, so to the best of my understanding when running a single 8 ohm cab the power output should be halved (150 watts)????

I was finding this set up struggling to keep up with my rock band, so i purchased the MAG 210T (200 watt - 8ohm) to run in addition to my current set up.......

When running both 8 ohm cabs the load should be 4 ohms correct?? meaning i should be getting the full 307 watts from the amplifier.??

Heres the problem.... It isnt any louder, it actually sounds worse when running both cabs, the speakers are farting and really muddy.

Any ideas why?

Worst case scenario i will sell the head and buy something that can run both cabs at full power, i would also like some recommendations if you guys have any...

thanks heaps for your help in advance, much appreciated.

Cheers

It is farting out and sounding bad because you mixed a 4X10 with a 2X10 without regards to power distribution.

Using two 8 ohm cabs split the amps output equally. Meaning you sent twice the amount of power to the speakers in the 2X10 that went to the speakers in the 4X10.

The 2X10 was overpowered and farting out while the 4X10 was not breaking a sweat.

I would place bets one of the cabs are out of phase. Plug a 1/4" speaker cable into the cabs, on the free end touch a 9 volt battery to the free end. Positive on battery to the tip of the plug. Speaker cones on both cabs should move away from the back of the cab (or at least all speakers the same direction). If the speaker cones don't move the same direction you have found the problem.

the 410 also sounds like its struggling, even so the 210 is rated at 200 watts so it should be able to handle it.....?

if this is the case how can i fix it?

The wattage ratings are the thermal limit which melts the voice coil - not the mechanical limit which is close to 50% of the thermal rating depending on how much low end you use in your EQ.

That cab probably runs out of gas shortly after 100 watts.

So theres no way to run both cabs and have it sounding any good??

Something's not right. These cabs were made for that amp so you shouldn't be experiencing this. In this instance the amp head doesn't have enough total output to bully your 210 even at full load, which it wouldn't be sending to only the one cab. That's impossible. I've used this exact cab setup with a MAG600 EVOII (600w @4) and the entire thing sounded peachy. No struggle from the cabs at all.

Check the Phase as B-String has suggested. This is very likely the culprit.

Additionally tell us about your instrument if you don't mind. Are you using an active or passive bass? Any pedals?

If all speakers in one cab move in the other direction have the wires reversed on the input plate of the cab. If only one of the 210 or one/ more of the 410's speakers do this reverse the wires at the speaker's terminals. With the positive at the tip all cones "should" move out (away from the back panel of the cab).

Out of phase would sound thin and tinny, not muddy as the OP describes

Are you daisy chaining the cabs,are running both cabs to the amp,if you are thats the problem,plug one to the amp and one to the cab thats in the amp,thats how you drop to 4 ohms

I use 2 bases with the same results, i have an warwick corvette $$ (active) and a spector legend 5.... No pedals.

No


"Daisy Chaining" one cab to the next is the same as connecting both cabs to the head - a parallel connection.

Not always true with multiple driver miss-matched multi-driver cabs.
With matching cabs most definitely.

Sorry mate i cant work out what your trying to say....
The amp has 2 outputs...... im running a cab from each output.
The cabs have 1 instrument jack and 1 speakon jack.
Should i use a speakon cable to link the two cabs together and run them from one input?

It is also possible to have a miss-wired speaker cable but check the cabs first with same cable on both cabs.

Parallel
 

8 ohms in parallel with 8 ohms yields a 4 ohm load no matter where the connection is made.

I vote for the condition that the 2-10's are over driven.

Trade the 2-10's in and get an identical 4-10 cab to match the one you already have.

I got the 210 to use for small jazz gigs ( easier to transport) but in the light it would seriously beef up my sound when used with the 410 for my rock band......
The cabs both sound great at low - mid volume but anything above that really sounds crap.

Honestly, as someone who has used Ashdown gear extensively before the thing that makes me most concerned is that you claim not to be able to hear any volume difference between the 410 on its own and the two cabs run together.

If all your items are working as they should you should definitely notice at least a noticeable increase in volume with 6 drivers as opposed to 4. This indicates to me that there's something wrong with one of your pieces of gear.

On this forum the predominant preference is always to run matched cabs, due to phasing issues that present themselves when operating cabs of differing size, wattage or brand. This train of thought has a lot of merit and is usually the best option, unless of course if you don't want 2 identical cabs for reasons of convenience. What you're experiencing is unusual and I don't believe it's a simple case of unmatched cabs.

The reality is that you have 2 really hot basses. The $$s and the EMGs in the Legend are both really full on sets of pickups. The MAG300 is a great amp but it's still only 300 watts. Perhaps you're punching too much into it for the headroom available but my gut feeling is that something's up.

Before you go selling or parting with anything take everything down to your local guitar store and talk to a professional.

You are using SPEAKER cables? Right?