Ampeg Micro VR issues poll with new video

[Maxend00d]

This is probably a stupid question, but do you notice any difference when plugging both the cabs to the head, or plugging one cab to the head, and Daisy chain from that cab to the next one?
I have two cabs with My micro vr and i have not experienced the problem in the video that was posted, but I have only had both cabs connected to the amp, never Daisy chained.

[JimmyM]

Originally Posted by Maxend00d

This is probably a stupid question, but do you notice any difference when plugging both the cabs to the head, or plugging one cab to the head, and Daisy chain from that cab to the next one?
I have two cabs with My micro vr and i have not experienced the problem in the video that was posted, but I have only had both cabs connected to the amp, never Daisy chained.

Doesn't make a difference.

[fenderhutz]

Well I finally got a response from Ampeg and I am going to break it down instead of just posting the response.

They read the forum. Saw my video. Now they can and have reproduced the issue but apparently it took a couple players with different styles and a couple different basses for them to replicate it.

Their answer? The sent my head I shipped back to the engineer that designed to pinpoint the issue now that they can "hear" what it's doing. This is the same set of engineers that denied early on there was no issue, maybe? Now they are looking for a fix from the engineer.

Still too early to say design flaw?

Oh. I have no answer WHEN I will have a fully working setup. Just it will take time to pinpoint.

[fenderhutz]

Also I would highly recommend to at least call if you have had the issue so when/if they redesign something for a fix you at least get a "fixed" amp (or whatever they decide the issue really is).

[JimmyM]

That is very good news. Your persistence will result in an even stronger product. You changed the course of history!

[beans-on-toast]

Originally Posted by fenderhutz

Their answer? They sent my head I shipped back to the engineer that designed to pinpoint the issue now that they can "hear" what it's doing. This is the same set of engineers that denied early on there was no issue, maybe? Now they are looking for a fix from the engineer.

Still too early to say design flaw?

I see this as a very positive step. Sending the video was good because it shows them in no uncertain terms what you are experiencing. Now they have said that they want to address the issue.

The engineers that designed the amp know it inside out. No matter how hard you try, when designing a product things can go wrong. It could be that the prototypes worked and when they transitioned to manufacturing, something went wrong. Sometime they have to cut corners post design to meet a cost spec. There could very well be a design flaw or a component not meeting specifications that their quality control didn't reveal.

I suspect that it won't take them long to figure out what the problem is and come up with a solution. Hopefully you will have a repaired amp sooner rather than later.

[Exploiter8]

u-boated

[fenderhutz]

Originally Posted by Exploiter8

u-boated

I have never seen that worded used to describe an action, that's funny.

[fenderhutz]

Originally Posted by JimmyM

That is very good news. Your persistence will result in an even stronger product. You changed the course of history!

You make it sound like I am Sir Isaac Newton on something lol.

I just hope they treat it as a universal issue and not put everyone through the ringer every time it gets reported. Ship back, make videos, etc.

[aborgman]

Originally Posted by fenderhutz

Still too early to say design flaw?

It was pretty obviously a design flaw once a half dozen instances on Talkbass alone surfaced.

Maybe still too early for them to ADMIT a design flaw though.

[fenderhutz]

Originally Posted by aborgman

It was pretty obviously a design flaw once a half dozen instances on Talkbass alone surfaced.

Maybe still too early for them to ADMIT a design flaw though.

Kinda my point. In my email communications with Ampeg they were very quick to shoot down any talk of that, and even in their last reply highlighted they were taking care of MY problem and MY amp was with the engineer. That's why I said it's important to call and report the issue.

[fenderhutz]

Well Chef contacted me about the review he did in Bass Gear magazine.

He mentions the issue, without really calling it a fault.

23185_BASG_ebook

[tombowlus]

Originally Posted by fenderhutz

You make it sound like I am Sir Isaac Newton on something lol.

I just hope they treat it as a universal issue and not put everyone through the ringer every time it gets reported. Ship back, make videos, etc.

FWIW, I put a plug in at Ampeg, as well, and let them know that I am experiencing the same thing with both of my Micro-VR/SVT-210AV/SVT-210AV rigs.

[Johno Dunn]

Originally Posted by tombowlus

FWIW, I put a plug in at Ampeg, as well, and let them know that I am experiencing the same thing with both of my Micro-VR/SVT-210AV/SVT-210AV rigs.

So Tom, just sell me 1 of your 210's and then I'll have the problem and you won't!

J!

[AlexanderB]

fenderhutz, I have read the thread and I just saw the video and I see your frustration. I would like to give a "technical" comment to what I see, if it is ok? Please bear with me...

A solid state amplifier is basically amplifying your bass' signal in two steps to deliver the output. The first step is to increase signal/ampitude. How much is basically decided by the position of the gain and volume knobs.
The second step is to "translate" the (now higher) voltage signal (in something called the amps drive stage) to something that can deliver current that will power the speakers. This takes place in the output stage of the amp.

The amount of total power is determined by voltage times current. (P=UxI) The voltage is set by your setting of the gain and volume.
But what determines how much current the amp will deliver?
The answer is that the speaker load will decide how much current the amp will deliver. The lower the load ("ohms") the more current will flow for a given volume setting. U=RxI. If we decrease R (ohms), I (current) will increase.

(Close to the end now...)

For this amp, there is very little power to be gained by adding a second cabinet. 4 ohm power is very close to 8 ohm.
So:
Since the power levels (P) are very similar even when load is changed (R goes down and I goes up), the level of clean voltage will drop.
You will reach the 200W/4 ohms at a lower volume/knob setting than you use for 150W/8 ohms. Or in other words, you will have to back off on the knob but will still be a bit louder with two cabinets. If you can borrow a SPL meter you might be able to confirm if your stack is 3 dB louder with both cabinets.

A "sturdier" amplifier might behave in a way closer to your expectations.

/Alexander from Sweden

[JimmyM]

Originally Posted by AlexanderB

You will reach the 200W/4 ohms at a lower volume/knob setting than you use for 150W/8 ohms. Or in other words, you will have to back off on the knob but will still be a bit louder with two cabinets. If you can borrow a SPL meter you might be able to confirm if your stack is 3 dB louder with both cabinets.

If that were what was happening, that would be excellent. But it's not. You can't get more volume with two cabs. Ordinarily you can, but this combination cause the head to clip in a nasty way too early and the avialable volume is way less than with one cab.

[AlexanderB]

OK. My post is primarily inteded to explain why you might be forced to back off on the volume once you add a second cabinet (in general).
Without any measurements it is very hard to know the maximum loudness for different configurations. However, I can clearly hear the sound clipping in spite of the limiter...

/Alexander

[GaryLC]

Hutzy,

I emailed Ampeg two days ago letting them now that I also have the exact same problem, and have been following this thread. I even referenced your name. So far I haven't gotten a response from them.

[tombowlus]

Originally Posted by JimmyM

If that were what was happening, that would be excellent. But it's not. You can't get more volume with two cabs. Ordinarily you can, but this combination cause the head to clip in a nasty way too early and the avialable volume is way less than with one cab.

IME, you can get more volume with two cabs (and without the head clipping), but perhaps not as much more as folks might reasonably expect based upon similar experiences of adding a second cab and going from 8 to 4 ohms.

[fenderhutz]

Gary that's odd. I have always gotten same day response, for the most part.