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Discussion Starter · #1 ·
The Helix V Twelve has unconventional amp channels. They do not support bridging. But, it can route additional power where needed. I read somewhere that it can do that more so if you don't use all of your channels because it has fewer channels to split the power into. Sounds plausible.

The Helix specs say 160 watt "max power" at 2 ohms, and 120 watts at 2 ohms if all channels driven the same. But, it doesn't say what the "max power" at 4 ohms would be. The "max power" is 1/3 more than standard power at 2 ohms. If same holds true for the 4 ohms with standard power at 75 watts, maybe "max power" at 4 ohms would be 100 watts. Is that right?

I'm expecting to use 8 of my 12 channels. So, presumably it can route more power to the channels I'm using. Will that be enough to power Esotec 3-way sets? Note that the Esotec mids and tweets are 8 ohms instead of the more common 4 ohms. Which presumably would cut the power available in half. It has crossed my mind to switch to Audiofrog for the mids and tweets and sell off my Dynaudio. But probably not necessary. I hope.
 

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This topic has been hashed over many times by folks with the same question as you.
 

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Your concern comes up routinely... Is that enough midbass wattage from the v eight/v twelve? Plenty will say yes but personally I like at least twice the power to my midbass than mids & tweets. To me the only way to get what I want out of the V twelve would be with dvc 2 ohm midbass. That would give you 240 watts per midbass and use 4 of the channels. Unfortunately you are extremely limited looking for this unicorn. I can only think of the AF GS8D2.
 

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The Mc443 amps would support that level of midbass power "need".
 
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Such a shame the V12 doesn't bridge, it'd be an amazing one box solution.
Amen to that! Huge oversight for my .02 worth!
 

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Discussion Starter · #7 ·
This topic has been hashed over many times by folks with the same question as you.
Well, I did try searching before posting. When I tried search for "helix max power 4 ohm" I got no relevant matches at all. When searching for "Dynaudio Esotec 8 ohm power requirements" I did get some hits somewhat related. Like a thread on 8 ohm speakers (not specifically about the Dynaudio) said that in general it isn't that important. It cuts the power in half but said that wasn't that important in the real world. As far as threads specifically on the Esotec, there was a variety of opinions but nothing I found happened to comment on the 8 ohm nature of the mids and tweets. Perhaps I missed it, but I did look. As far as Esotec power requirements, most people seemed to say 100 would be plenty, though some others said that Dynaudio are power hungry and they give them 150. But none of the ones, at least as far as I found, specifically addressed the ohms vs power, though as noted, the one thread on 8 ohm speakers said in general its not a big deal. Bottom line is, I did search, found nothing on the helix max power 4 ohm, and some somewhat related threads on the Dynaudio 8 ohm issue, but not exactly the same as what I was asking. I didn't see any other thread discussing using Esotec's with a V Twelve or V Eight.

Now, sure, maybe I didn't use ideal search terms, I'm just saying I did try.

Your concern comes up routinely... Is that enough midbass wattage from the v eight/v twelve? Plenty will say yes but personally I like at least twice the power to my midbass than mids & tweets. To me the only way to get what I want out of the V twelve would be with dvc 2 ohm midbass. That would give you 240 watts per midbass and use 4 of the channels. Unfortunately you are extremely limited looking for this unicorn. I can only think of the AF GS8D2.
I had never heard of dual voice coil on a midbass. Interesting. But, fitting an 8" in my door would be difficult. But very interesting idea!!! Thanks.

Amen to that! Huge oversight for my .02 worth!
My guess (could be wrong) is that the lack of bridging wasn't an oversight per se. They didn't "forget" to include bridging. Rather, I suspect, it has to do with how the amps are designed. Their M4 which does support bridging is spec'ed as Class D. While the V Eight and V Twelve are spec'ed as proprietary Class GD. Which they claim is superior to regular Class D. But might not allow for bridging. And their dynamic power allocation, giving more power where needed might also work against being able to be bridgeable. Note this is pure speculation on my part, I'm just saying that I doubt it was an accident that bridging isn't an option.

Bottom line is, I'm going to initially just use the V Twelve amp channels, except of course for the subs. If I find it insufficient power, I will add an amp for the midbass. Or, look again at fitting the GS8D2 in the door.
 

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the match amps have dual (120/150?) watt "subwoofer" channels that could be midbass for sure, then enough for l/c/r and rear fill with i think sub out and optical in. might be a good option if you don't need 12 channels. it seems like there is demand in the market for a solution that has more juice for midbass, if enough people request it maybe they could add a pair of Psix 120watt channels in a future offering. this is the essence of the buyer is always right, which is to sell the buyer what they want, which may not be whats "best" for them or "needed", if the demand is there eventually someone will supply it. the match seems well suited for this and seems aimed at the bmw market that has the front underseat "subwoofers".
 

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Well, I did try searching before posting. When I tried search for "helix max power 4 ohm" I got no relevant matches at all. When searching for "Dynaudio Esotec 8 ohm power requirements" I did get some hits somewhat related. Like a thread on 8 ohm speakers (not specifically about the Dynaudio) said that in general it isn't that important. It cuts the power in half but said that wasn't that important in the real world. As far as threads specifically on the Esotec, there was a variety of opinions but nothing I found happened to comment on the 8 ohm nature of the mids and tweets. Perhaps I missed it, but I did look. As far as Esotec power requirements, most people seemed to say 100 would be plenty, though some others said that Dynaudio are power hungry and they give them 150. But none of the ones, at least as far as I found, specifically addressed the ohms vs power, though as noted, the one thread on 8 ohm speakers said in general its not a big deal. Bottom line is, I did search, found nothing on the helix max power 4 ohm, and some somewhat related threads on the Dynaudio 8 ohm issue, but not exactly the same as what I was asking. I didn't see any other thread discussing using Esotec's with a V Twelve or V Eight.

Now, sure, maybe I didn't use ideal search terms, I'm just saying I did try.



I had never heard of dual voice coil on a midbass. Interesting. But, fitting an 8" in my door would be difficult. But very interesting idea!!! Thanks.



My guess (could be wrong) is that the lack of bridging wasn't an oversight per se. They didn't "forget" to include bridging. Rather, I suspect, it has to do with how the amps are designed. Their M4 which does support bridging is spec'ed as Class D. While the V Eight and V Twelve are spec'ed as proprietary Class GD. Which they claim is superior to regular Class D. But might not allow for bridging. And their dynamic power allocation, giving more power where needed might also work against being able to be bridgeable. Note this is pure speculation on my part, I'm just saying that I doubt it was an accident that bridging isn't an option.

Bottom line is, I'm going to initially just use the V Twelve amp channels, except of course for the subs. If I find it insufficient power, I will add an amp for the midbass. Or, look again at fitting the GS8D2 in the door.
Did you actually use the link I provided to improve your search results? If so, you would have stumbled across my thread on the exact same topic roughly 1 year ago.
 

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you can:

1) use your regular V12 preouts for sub mono
2) take 2 of the V12 channels and connect them to a P Two via high level input ,all you need to do is match the V12 speaker outputs via dsp software DB settings to P Two input

then you have yourself the flexibility of the V12 with the addition of 10x 75rms + a monsterious 2x280rms all at the size of a regular AB class 4 channel amp
 

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Geo dug into this V twelve stuff and as I remenber the issue is the 75watt is achieved as each channel is actually a push-pull pair already, looking at this picture you can see 24 blocks deployed in pairs:

301390
 

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It's just a design route; where as some amps like a AP F8.9 is a 8 channel amp where each output has a single discrete amp section, so you can pair two channels in a bridged mode (one pushes, one is 180 inverted and pulls, to give a doubling of output); the Helix v12 actually has 24 amp sections already paired to make the 12 outputs, so as they're already paired you can't bridge a bridge.
 

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It's just a design route; where as some amps like a AP F8.9 is a 8 channel amp where each output has a single discrete amp section, so you can pair two channels in a bridged mode (one pushes, one is 180 inverted and pulls, to give a doubling of output); the Helix v12 actually has 24 amp sections already paired to make the 12 outputs, so as they're already paired you can't bridge a bridge.

thanks for the reply,



upto date head units manage 70rms when 1 of the 2 rear channels arent connected, micro 4 channel entry level amps even produce 150rms when bridged.kind of makes me question just how good these amps are.


also since its internally bridged already wouldnt that be bad in terms of heat and thd if we connected 2ohm speakers to these amps?
 

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out of curiosity what would that mean in technical terms? is that good or bad thing?
It means each amp channel is already bridged inside the amp. There are actually 24 channels bridged down to 12 at the amps outputs.
 
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I'd say they know what they're doing here, it looks nicely laid out and I just accept that it's perfectly good for my use (V eight) as a OEM replacement amp.
I own a V Eight and V Twelve. Hopefully you gather from this I like these amps and that they are adequate for me as well.
 

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also since its internally bridged already wouldnt that be bad in terms of heat and thd if we connected 2ohm speakers to these amps?
No. As a matter of fact the amp hardly gets warm to the touch. It is extremely efficient.
 
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Looking at wiring up a V8, and which chan to use for what. Given I'm only using 7 chans and one is a center with limited power, would it make sense to seperate the banks to get as much as I can for the potential overdrive on the bass units? This assumes the amp has two power domains, left and right:
301472


Left:
  • 8" bass
  • 8" bass
  • Centre 4"
  • unused

Right
  • FR Mid + tweet
  • FL Mid + tweet
  • RR Mid + tweet
  • RL Mid + tweet
 

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Discussion Starter · #20 ·
Okay, so, I got the system installed. Overall pretty nice. Though I do wish I had some more midbass power. I hadn't come back to this thread in a while. I did not think about the fact that it has limited preouts. I just assumed (incorrectly) that the DSP channels would have preout as an option. If I had realized at the time of purchase that it didn't work that way, I probably would have gone with an Ultra DSP and separate amps. Well, live and learn.

Someone suggested the idea of the dual voice coil Audiofrog, and for a hot minute, I thought about going that route. But, the reviews on it not too impressive. So, that leaves me with, accept it as it is, or, possibly what audiocholic said:

1) use your regular V12 preouts for sub mono
2) take 2 of the V12 channels and connect them to a P Two via high level input ,all you need to do is match the V12 speaker outputs via dsp software DB settings to P Two input
Using a high level input seems suboptimal. Do many people do that? It is an interesting idea? If I happened to want to use some other brand for the amp, would it work as well?

Thanks everyone for the help!
 
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