The AccuGroove Situation - I'd like an answer: Anyone else?

[getz out]

You didn't miss anything, Jeremy. That's exactly the point; it sounds the same in either position. Shouldn't it be louder in one position than the other?

 

Your meter is testing DC. DC doesn't matter. The current from your amp is coming as AC. If you hooked up two of those Tri210L cabinets to your amp in the "8-ohm" position, your amp would actually be seeing a 2-ohm load (since they are really 4-ohm cabinets) rather than a 4-ohm load, because the switch isn't actually doing anything.

 

Your amp can handle 2-ohms, so no sweat.

 

However, not every amp can handle 2-ohms. Most can, even if they aren't rated at 2-ohms.

 

But that isn't nice, is it?

 

POINT

 

With switches in 4-ohm position:

 

Tri210L + Tri210L = 2-ohm load

 

With switches in 8-ohm position:

 

Tri210L + Tri210L = 2-ohm load

 

No one's amp has blown up because most amps can handle this load.

 

Meaning, you could hook up two 4-ohm cabinets, so what makes the AccuGroove cabinets any different? That makes the AccuSwitch utterly worthless and false advertising. Worse, operating outside of the constraints of a user manual for an amp could void your warranty. Not so cool.

[Gruuve]

Perhaps Mark did the same thing as Jeremy, eh?

 

Jeremy, find a friend who has an oscillascope and signal generator. Put the cab on that apparatus, and run an AC frequency through it that's around the area where the low frequencies start to roll-off (the cab's resonant frequency, somewhere under 100Hz). From what I gather, you'll see 4-ohms or so with the switch set to 4-ohms, and 4-ohms or so with the switch set to 8-ohms. The capacitor network simply makes the second driver disappear from the circuit where DC is concerned. However, the current coming out of your amp and going into your cab isn't DC...it's AC, so the second driver doesn't disappear.

 

The real question is: did Mark simply mis-design this (ie. it's an honest mistake), or did he intentionally misrepresent this feature? It's awefully hard for me personally to believe that someone with enough technical knowledge on this subject to be capable of designing a very flat response cab wouldn't have the knowledge to know the DC vs. AC results of this gadgetry. However, I am still watching for Mark's commentary on this. I PM'd Mark a few days ago and let him know that he really needs to respond to this thread. He said that he was preparing a response. To me, no response from Mark would certainly be read as an admission that Andy's article and BP's commentary is right on the money. When/if Mark does respond, I'll digest that info when I have it.

 

Things aren't always as they seem, so I'm trying to keep an open mind about this whole thing. However, I can also say that "where's there's a little smoke, there's usually a little fire".

 

Dave

[ArwinH]

From my few interactions and conversations with Mark I know that he is a good, honest guy, and I earnestly believe that his response will give a logical explanation to the whole ordeal, until then I'm gonna be on the edge of my seat .

[g.]

From my few interactions and conversations with Mark I know that he is a good, honest guy,

- Probably best not to mix personal assessments of people with the actual technical matters. It's bad enough to be wrong about one or wrong about the other without confusing in ones' own mind what the hell they are actually trying to determine.

 

and I earnestly believe that his response will give a logical explanation to the whole ordeal, until then I'm gonna be on the edge of my seat

This is an example of what I mean. High logic has already been spoken by some educated professionals and due to the personal angles a lot of shouting and gnashing of teeth has confused just about as many people as the actual presentation of data may have educated or made people think.

 

But when you place personalities in the mix it just comes down to who you think "the nice guy" is without actually understanding the science or attempting to. Heck, some people are even denying their own knowledge of electronics they have become so embroiled in the personalities thing.

 

Who is nicer? Mark? Andy? Jim? Bill? Well, only God truly knows that, and the issue isn't who is prom king or has the best social skills (remember also that some people have used these to very bad ends all through human history). No, the issue is:

 

DOES THE ACCUSWITCH meet its claims? The claims are that it actually allows the cab to operate at either EIGHT OHMS or FOUR OHMS without any other change. Period.

 

A epoxy-potted subassembly with two wires coming out that acts like a capacitor in every respect so far only has one explanation. It's a capacitor or several. If there is an explanation other than that, it will be very big news in the world of electronics I would think, and not just the world of bass cabs.

[ArwinH]

Thanks for setting that straight GB.

I can respect your the idea of keeping the technical side of this question free of any personal ties and dividends. I'm just not going to discredit any technology introduced until we get a much anticipated response from whappo.

[getz out]

I'd advise against holding your breath.

[a boy named sue]

Originally posted by greenboy:

Could you clarify/restate what you just said?

My previous post was based on the assumption that the acuswitch was designed to

bypass some low impedance protection circuitry on certain power amps. I've done

no research into whether any poweramps actually measure resistance to

automatically switch off, but it seems to be a possibility given the reported

response by acugroove to the BP article.

 

Obviously if no amps actually do such a check then the conclusion I reached is

purely hypothetical. I think/feel it is fine to build such a product

and advertise it in a dishonest way provided that an interested costomer is

informed as to what is actually going on. This is analogous to advertising "fee

free" accounts by banks who then simply lower the savings interest rate. So long

as the potential costumer can find out the savings interest rate no real harm is

done. However, I don't think that an interested customer could have found out all of the

relevant facts in this case.

 

Note that I have no actual knowledge of how modern poweramps are protected.

Personally I'd put a fuse on the mains input and a temperature switch somewhere on the

heat sink...but I'm not an EE.

[Gruuve]

I've slept on this issue. I'd have to say, in reviewing the evidence so far (mainly that BP tested the AccuSwitch on a scope and found that it did nothing when an AC signal was applied), that I personally have no other choice at this point but to believe Mark has misrepresented this AccuSwitch. Whether he did so purposefully or not still remains a question, however, it's difficult for me to believe that it's simply an honest technical mistake. In my mind, Mark's credibility is pretty much shot. The AccuSwitch is in the same category as "health magnets" in my mind.

 

Which leads me back to the sensitivity question we discussed once before. If Mark mis-represented the AccuSwitch, how do I know he isn't misrepresenting the unusually high sensitivity for a flat cab as well. What else could be misrepresented about these? The thing that really bugs me about this is that this misrepresentation could lead to someone damaging their amp needlessly. Would Mark reimburse you for an amp damaged by his AccuSwitch? I seriously doubt it. I don't believe this is a company I'd want to give my business too at this point.

 

Either you endeavor to maintain high ethical standards in your business operations, or you don't. When you're a small company (with one person making all the business and technical decisions), this is particularly important because the company is a direct reflection on the person running it.

 

I have no doubt that the cabs sound great, but that's not the issue here. Don't necessarily go sell your AccuGroove cabs just because the AccuSwitch is a fake. If you like your "health magnet" AccuSwitch, by all means enjoy it, but only use the 4-ohm setting so that you don't eventually damage your amp.

 

If Mark responds with an explanation that makes some sort of sense, then I'll reconsider my position on this.

 

Dave

[g.]

Hoi, Dave,

 

I kind of covered how common it is to see inflated specs in the bass rig sector - it's more the rule than the exception really... I was shocked at both the efficiency and the freq response ratings for especially one company's products when first entering the world of bassin' as a player - surely if this company and others were so far ahead of SR in driver and cab design some of that incredible advancement would find its way into touring and club PAs...

 

It didn't take long to figure out it was a common practice to play numbers games on paper, and that any bass rig company who didn't was in the minority and at a strict disadvantage among the credulous, both for marketing/sales, and bragging rights of those who had already purchased (which has considerable influence on future buyers since the internet came along).

 

Another example comes from the guitar sector, but I've seen it in the bass crowd too: amps/combos that have most of their gain play at the first part of the knob... A guitarist about 7 bands ago was notorious for sudden volume shifts within a song or setlist. It was scary bad to be anywhere near the fron of his 212 combo - really a bughtmare for a bassist because as a rhythm player he was all over the map with tempo, even within a phrase!

 

The volume problem was largely that almost all of his pregain and postgain/master volume was within the first three numbers of the knobs, and just bending down to make a hairline adjustment could put the SPL into the next league. Even worse when channel-switching came into play because the knob for the other channel's pregain would get turned without hearing it until it was time to channel-switch.

 

But hey - great bragging rights on internet forums: "My amp only needs to have its pre and post turned up to 3 to smoke any Marshall around. Take THAT!" I've seen this a lot on bass forums too, and newbies seem sucked in to this.

 

Somewhat meandering, but I think indicative of the mentalities at play. That's why I think it'd be good to buy a few consonants and vowels from the SR industry so companies could get on with competing with their REAL assets: service, quality, true innovation, etc.

[Jimbroni]

 

Will somebody wake me up when this threads stops?

 

Maybe if we channel our energies on 4 ohms vs 8 ohms in yogi fashion, (OHM OHM OHM OHM), all of our basslines will become funkier.

[getz out]

From another forum:

 

http://www.talkbass.com/forum/showthread.php?p=2459963#post2459963

 

Man, the guy who posted that really knows how to put things into perspective.

[Pernax]

Yeah, I heard he was also really wise in the ways of science, and when questioned about the situation at hand, his response was - a duck!

[Luke73]

Originally posted by getz76:

From another forum:

 

http://www.talkbass.com/forum/showthread.php?p=2459963#post2459963

 

Man, the guy who posted that really knows how to put things into perspective.

Wow! I gotta get me a Digilog Dynamicator!

 

I don't believe they're an empty box, all the pros using them sound so good!

 

 

ROFL

[getz out]

Luke, I have one occupying the empty rack-space in my Demeter/Stewart rack. Best piece of gear I've ever owned; works as stated and extremely reliable. Plus, it's 100% analog.

 

Here's another take:

 

I really wish AccuGroove would reply or post something on his website; even the anecdotal response they gave the Bass Player review.

 

I still don't understand why they would put the switch in there. A very bad business decision no matter the situation: (1) if AccuGroove was fooled by a dubious engineer, they should have done better research and (2) if AccuGroove was trying to be dubious, they should have had the forethought to realize they would be exposed.

 

The problem this has created for AccuGroove is troubling. People are taking a closer look at the specifications of some of the boxes and are questioning other claims.

 

Reason people are willing to spend so much money on the cabinets:

 

(1) Sounds Great

(2) AccuSwitch

(3) Excellent Construction and Specifications

 

While companies like Eden, Ampeg and SWR obviously exaggerate their specifications (the Eden D210XST does not produce 103dB at 30Hz), the average AccuGroove (or Epifani or Bergantino or Acme) buyer is not the same as your average buyer. The expect more clarity and transparency in the advertising from their manufacturer. Does a relatively small box (considering the number of drivers) like an El Whappo really produce 96dB at 29Hz? Seems hard to believe when dedicated subwoofers costing thousands of dollars in much bigger boxes produce similar results.

 

Mark from AccuGroove said in a thread Dave Sisk started:

 

Are our specs correct? You bet your low B string!

If that ends up not being true, it doesn't change the fact that the cabinet isn't fantastic. However, I would feel a bit cheated if I was the purchaser, much as I would feel if the specifications on my Acme or Bergantino cabients were not true.

 

The scary thing is the AccuSwitch debacle is textbook material for class action litigation. This is a stronger case than say something like the battery class action taken again Apple's iPod. If someone wanted to put the screws on to AccuGroove LLC (say a competitor), they could try to define a class that was (a) observed the advertisement or materials regarding the AccuSwitch and (b) purchased an AccuGroove cabinet with an AccuSwitch. How much is the AccuSwitch functionality worth? $50? $100? $200?

 

I don't think there is enough volume to make it feasible, but if someone had a personal vendetta... I hate class action litigation, by the way. In all scenarios, the defendant gets hurt badly, the plaintiffs don't see much of anything, and two lawyers make a good amount of money.

[g.]

Yep, Getz, that's probably a pretty good estimate of the situation and the ramifications ... It would be great if the basscentric industry as a whole took this situation as a kick in the pants to participate in the AES, use the same testing procedures and specs guidelines, etc.

 

But I see one thing standing in the way: most of them have specs out there (some of them have for decades) that would change drastically were they actually based on such guidelines.

 

...Were I to post such a suggestion on talkbass it probably would at least get discussion since tb has a few more participants who also are technically astute and have in their own posts decried the state of specsmanship the bass rig industry wallows in. It would probably be HEATED discussion though, since some of the participants would feel exposed, and many sacred brand name dogs would be kicked while others would take offense that their religious icons were under scrutiny.

[a1bassguy]

I agree that Accugroove's answer is rubbish. Prior to this 'exposure', I had assumed that they were achieving load switching by using speakers with dual voice coils. I guess they are not.

 

Maybe BPM needs to do spec testing as part of their reviews on amps and cabinets? Sort of like the Electronics and Audio magazines do. We can get the real power output for amps at various loads and the real db and response curves for cabinets.

 

This would surely be very controversial and force the manufacturers to be honest, just like the high-end audio manufacturers are known to be with their specs. Anything less is deception and fraud by the manufacturers.

[Eric VB]

Originally posted by a1bassguy:

Maybe BPM needs to do spec testing as part of their reviews on amps and cabinets?

Reading greenboy's posts and knowing that at least part of BP's role is (or should be) to offer independent, unbiased reviews of gear to their readers, I don't see why it shouldn't go the extra mile to be the Consumer's Report of bassdom. By that I mean BP should conduct the extensive testing that greenboy is advocating. Of course, if that would necessitate a doubling in cover price, for example, it would probably not be worth it.

 

I suspect it won't happen, though, because the bottom line for any business is always money, and BP wouldn't want to lose advertising dollars by exposing the Emperor's new clothes on such a large scale. That is, if we were to find out that our "bass" rigs weren't any better for our purposes than other SR equipment, or that we were paying significantly more for little benefit, what would be the end result?

[getz out]

Give credit where credit is due; Bass Player took issue with a product that has been steadily advertising since inception. They could have walked away from the issue and just asked for an explanation, but instead they really went after what they thought was a misrepresentation of facts.

 

There's another issue; Bass Player doesn't have the kind of circulation Consumer's Report has. Consumer's Report can afford to either buy products for testing or strong-arm a manufacturer to submit a product for testing. Bass Player relies on submissions from manufacturers for reviews. When they did the 4x10" cabinet shoot-out, they received submissions from manufacturers, they didn't buy the cabinets. Same when they did the 5-string bass shoot out.

 

It is up to us as consumers to be aware that we are often comparing apples and oranges. Does anyone who has half an ounce of understanding of the laws of physics truly believe that the Eden D210XST produces 103dB at 30Hz? That doesn't mean it isn't a good cabinet, but the specifications produced by Eden are utterly useless (unless you are trying to compare them on a relational basis with other Eden cabinets).

[g.]

SR and recording magazines and web sites may verify tests that manufacturers have provided (and there seems to be a lot of peer review too among AES at times), but it's the manufacturers' responsibility to provide specs and adhere to testing conventions. Indeed, placing the onus on BP would have severe financial repercussions because of both advertising dollars and the cost of reviewing always at such depth.

[g.]

getz76: Give credit where credit is due; Bass Player took issue with a product that has been steadily advertising since inception. They could have walked away from the issue and just asked for an explanation, but instead they really went after what they thought was a misrepresentation of facts.

Yep.

 

It is up to us as consumers to be aware that we are often comparing apples and oranges. Does anyone who has half an ounce of understanding of the laws of physics truly believe that the Eden D210XST produces 103dB at 30Hz? That doesn't mean it isn't a good cabinet, but the specifications produced by Eden are utterly useless (unless you are trying to compare them on a relational basis with other Eden cabinets).

Actually you can't even depend on that for a couple of reasons. One is that different product cycles often have different people involved at the marketing and engineering levels, ones who have a different idea of what testing procedure to use (if any), and what marketing claims need to be made to have any chance against the "textual armaments buildup" their competitors may have forged ahead with.

 

Another reason is that two specs - for example, SPL/efficiency - arrived at by the same means by the same people STILL may not tell you enough about say the low end response and ability to handle a lot of energy down there if the spec is based only on weighted averaging, or 1 KHz, or wherever the peak SPL is. That's also another reson defined meaningful specs definitions are superior to ones that really don't tell much.

[Pernax]

Advertising dollars aside, I too would really like to see comprehensive gear tests conducted by BP on a larger scale (i.e. measuring the specs with a fine toothed comb etc.). That would give them an edge on their reviews, which in my opinion don't have that much to offer when compared to what can be found (once filtered) on the 'net. Too bad it won't happen, for obvious financial reasons.

 

-P

[Eric VB]

Originally posted by getz76:

Give credit where credit is due; Bass Player took issue with a product that has been steadily advertising since inception.

Credit given. But this was an isolated case. My statement alluded to BP calling all manufacturers' claims. BP can probably afford to lose one advertiser, but not all of them. That was my intended point.

[lug]

The AccuGroove Situation - I'd like an answer:

 

 

I found the answer! It's 42.

[jeremy c]

Just out of curiousity, do these products work?

Does the engineering have anything in common with the AccuSwitch?

 

SpeakerMate

 

MonsterCable Speaker Switcher

[g.]

I haven't looked into them, but off the top of my head I'd assume they are basically RESISTOR networks (if they actually aren't snake oil). Resistor networks take a toll on performance however.

 

EDIT: just skimming the SpeakerMate site and from what actual tech info I can glean, it appears that when used in compatible speaker configs, the Speakermates are acting as switchable parallel/series networks, much as is done within various 2-by and four-by cabs, or sometimes guys will jury-rig an external cable to change series connection into parallel in attempt to make use of all their cabs.

[getz out]

Per the MonsterCable websited:

 

High current resistors with aluminum finned heat sinks for maximum power delivery, up to 150 watts per channel.

[Eric VB]

The SpeakerMate online lit. states that it works on "Self-Switching Topology": "a multitude of speaker hookups [...] in series, parallel, series-parallel and parallel-series (or combinations of these)." So no, they're not simply using a capacitor. Also, their claim is that "SpeakerMate was designed to allow connecting a wide array of multiple, impedance matched speaker cabinet pairs as well as some mismatched impedance triple-cabinet setups to just about any amplifier available today." Specifically, they do not claim to be able to switch the impedance of a driver from 4 to 8 ohms.

 

Does anyone know if AccuGroove ever used impedance in their claims for AccuSwitch? I think there's some wiggle room if they simply said it could switch between "4 and 8 ohms" instead of "4 and 8 ohms impedance", as Jeremy's trusty voltmeter (set to measure resistance) points out.

[g.]

Actually impedance would be implicit anyway, because all practical use of speakers is based not on resistance but nominal impedance, and for the switch to truly meet its claims that would be the paramter one would be concerned with.

[g.]

Neither method is a way to get full power out of an amp and deliver maximum SPL. The Speakmate method while allowing one to heap a bunch more cabs into the equation (should someone prefer 6 weakly driven monitors to 4 fully-driven ones) will often take its combinations into sum impedances that have the amp producing but a fraction of its power, the other method seems to be using "dummy" resistors to bring the load up, dissipating power in heat (instead of SPL).

[g.]

RBG, I take it you are versed in 70-volt transformer distribution systems?