Big E Speakers Part 4 - Quadraphenia

[MarkA]

TE="greenrositti, post: 16558902, member: 113319"]I always attributed it to ear fatigue and guitards. Until I learned about thermal compression a few years back...[/QUOTE]

Those (ear fatigue and the other) are both still real phenomena.

 

[Stephen Regier]

So I am not being sarcastic here. Would it benefit one to take a small fan on a hard driving gig, and point it into the port at the breaks. I am not just talking MVW cabs but any ported cabs.

I do not think a fan would push enough air into the driver chamber to provide much benefit. A large heatsink would work. Some manufacturers like Cerwin-Vega use them in their high power folded horns to provide cooling to the transducer in the sealed driver chamber. The MVW has a supercharging effect in the driver chamber which enhances motor cooling. Reflex designs that encorpoate motor cooling place the port inlet in close proximity to the motor structure.

 

[3rdcurve]

Got to play through the MAS112 at tonites jam session. Fantastic.

 

[3rdcurve]

Question for Mike, could owners of existing 8 ohm 112s need to change out the crossover as well as the woofer to make the 4 ohms?

 

[Mike Arnopol]

Private message today to me from Zoran Todorovic at Sonic Farm:

We talked to Mike Arnopol who suggested we work on a bass amp. This will happen down the road, but is not one of our priority projects time-wise. Yes, the input circuit would be the same as the one in 2DI4.​

Just to clarify. Just talked to Boris (the other Sonic Farm guy). When Ukiah talked to Zoran they were frantically getting stuff ready for the AES show. Now after things have settled down we are going over eq points, et al.. They will start working on it next month. The power amp section is a done deal so it's just figuring out eq and engineering it into a box. Probably mid next year to bring to market. But it is happening.

 

[Mike Arnopol]

Question for Mike, could owners of existing 8 ohm 112s need to change out the crossover as well as the woofer to make the 4 ohms?

Yes. But it is a very different voicing than the 8 ohm MAS112. VERY flat, warmer (but fast and controlled) low end, and it's native voice is a flatter midrange. I have a switch to boost the mids, but it's still a fatter voicing than the 8 ohm 112. The MAS112 was designed for clarity and power. That's what the 8 ohm version does. The 4 ohm version is a different cab.The 112/8 pushes in the low to mid bass. The 210 Flex pushes in the mid to upper bass. The 112/4 pushes in the low to upper bass. Very even across the bass range. The 112/4 is more of the voicing that I'm looking for. But most guys want the extra mids and clarity of the 112/8.

If I were to pick the one for rock to fusion I'd choose the 112/8. For fusion to funk, r&b---the 112/4. But--- to be honest---if you don't mind expending the calories to twirl a knob---with a little eq--either can come close to the other's voicing.

 

[3rdcurve]

Thanks for the clarification Mike!

 

[mothra2]

Just to clarify. Just talked to Boris (the other Sonic Farm guy). When Ukiah talked to Zoran they were frantically getting stuff ready for the AES show. Now after things have settled down we are going over eq points, et al.. They will start working on it next month. The power amp section is a done deal so it's just figuring out eq and engineering it into a box. Probably mid next year to bring to market. But it is happening.

And the power amp section is...

 

[spiritbass]

And the power amp section is...

I think we're talking 1,000 watt ICE module.

 

[J.Wolf]

The new 700 w ice module is pretty happening too. I like It way more than the 800 (puma, mb800, Minnie, th500 etc..)

The 1000 is amazing though. So quick and punchy. Very non-digital feeling.

 

[mothra2]

There's something here I'm just not getting...

Waaaay back when those 1000's were brand new, a speaker builder that was using them asked me what I was currently using when I went to try one of his builds out. I said CA-9, and he just laughed and said..."well, you really don't expect this to sound like THAT, do you???"

So. What has changed for that old module???

 

[J.Wolf]

IMO nothing.. A ca9 is a ca9 and no class d module is going to sound/act/respond like it. The newer high power ice modules (and hypex) seem to be clearly better than the 800 that everyone uses, but if you're wanting one to compete with a CA9.. Ain't gonna happen

But I can't imagine hauling a ca9 around anymore, so I'm (for one) relegated to finding the best lighter weight, smaller option, knowing full well it ain't gonna be lead sled loveliness

 

[mothra2]

+1...I did get the impression, though, that Mike seemed to think it was 'there'... Perhaps I've read a bit too much into his posts

Also, very surprised that after all this time that the new 700 wouldn't be better...

 

[J.Wolf]

I did get to hear the Demeter head by itself, and pre out > 700 module. IMO fwiw, the 700 sounded smoother, rounder, and less 'grainy' by comparison. A pretty crude and quick comparo but that was my takeaway. The 1000 has more 'effortless slam' IMO than the 800 which is a term Id use to describe the ca9, but i am not saying it is on par with that amp.

 

[mothra2]

Speaking of Sonic Farm though... :>)

 

[JGR]

IMO nothing.. A ca9 is a ca9 and no class d module is going to sound/act/respond like it. The newer high power ice modules (and hypex) seem to be clearly better than the 800 that everyone uses, but if you're wanting one to compete with a CA9.. Ain't gonna happen

But I can't imagine hauling a ca9 around anymore, so I'm (for one) relegated to finding the best lighter weight, smaller option, knowing full well it ain't gonna be lead sled loveliness

The CA9 is a great amp and I loved mine. A big part of the appeal and perceived performance is due to the input sensitivity which makes it very easy to drive - this often provides for more headroom and/or less loading on the preamp, and this benefits a lot of the lesser preamp designs that aren't quite up to snuff in terms of driving PA style power amps in terms of clarity and punch/dynamics.

I moved from a CA9 to a PLX 3602 which has even better performance with less weight and a more reasonable form factor. When I take the preamp out into the PLX, there isn't any noticeable degradation in performance compared to the integrated amp (1000asp). Nada.

 

[MarkA]

I did get to hear the Demeter head by itself, and pre out > 700 module. IMO fwiw, the 700 sounded smoother, rounder, and less 'grainy' by comparison. A pretty crude and quick comparo but that was my takeaway. The 1000 has more 'effortless slam' IMO than the 800 which is a term Id use to describe the ca9, but i am not saying it is on par with that amp.

When I picked up my cab, I briefly tried my HBP-800D through its internal power section, then the 1000W Ice module (in the form of JGR's 1000W Ice-module based power-amp), then the 700W Ice (in the form of a box that Mike and Radbass put together). Given that I don't know what, if any, signal-shaping/circuitry is in the HBP between the preamp and power section and that there might be differences between the two "Iceboxes" aside from the module inside, the 700 also struck me as smoother and "less grainy" than the Demmie's internal power section. Nice extension up top, tight and clean down low. The 1000W Ice felt a little less present up top than the 700W, but the low end had more heft and authority. I didn't max out the volume on any of these amps (though I did get loud enough earlier to draw the attention of a neighbor -- sorry, Mike. Sorry, neighbor.), so I don't know how they'd behave at their limits (or where the limits of the 700 would fall vs. the 800), but, with the Demmie as a front end, the 700 was my favorite, followed closely by the 1000, followed by its own internal power. I also tried running Monique through the Iceboxes and through the effects return on the Demmie. With Monique in front, the HBP-as-poweramp was my favorite overall (the little bit of grain/texture enhances the top-end presence of Monique, IMO, and the Presence control on the HBP, if you want to use it, is voiced to work very well with the smooth Monique), followed by the 700, followed by the 1000.

Both the 700 and the 1000 felt cleaner, quicker, and had a more cohesive attack in the lowest register than the 800 in the Demmie. That said, the Demmie is no slouch as is, and kicks harder than the vast majority of class D heads I've heard.

I've never had a CA-9, so can't compare there. Closest I've come is my GBE 1200. The 700 doesn't have the heft/slam of the GBE. I won't venture a comparison between the GBE and the 1000 other than to say that they feel different, but both the 700 and 1000 felt more lead-sled-like -- more solid, more immediate, less harsh -- than other class D implementations I've tried.

With the Demmie, the 700 felt a little more balanced and extended (or maybe just present) up top than the 1000. That's not to say the 1000 can't reproduce a present and detailed top end -- I think I said earlier in this thread how much I dug JGR's Box O' Tone straight into his 1000W Icebox (no EQ), then into the 112 -- super lively, super detailed. That combo was very responsive, with no lack of extension and plenty going on up top.

 

[MarkA]

The CA9 is a great amp and I loved mine. A big part of the appeal and perceived performance is due to the input sensitivity which makes it very easy to drive - this often provides for more headroom and/or less loading on the preamp, and this benefits a lot of the lesser preamp designs that aren't quite up to snuff in terms of driving PA style power amps in terms of clarity and punch/dynamics.

I moved from a CA9 to a PLX 3602 which has even better performance with less weight and a more reasonable form factor. When I take the preamp out into the PLX, there isn't any noticeable degradation in performance compared to the integrated amp (1000asp). Nada.

Hey, Jon, I started typing my above reply, then got something to eat while you were typing this -- I guess input sensitivity would be a pertinent factor (one of which I'm ignorant) with both of the poweramps I tried and the Demmie's internal power. My little A/B/C was hardly scientific -- while I feel confident in my observation of the results, I can't say anything definitive about the cause(s).

What you say about the 1000W Ice is certainly encouraging. I thought it stellar with the BoT, and imagine your amp is even better. What is the input sensitivity of the power-amp you put together, if you don't mind my asking?

 

[JGR]

Hey, Jon, I started typing my above reply, then got something to eat while you were typing this -- I guess input sensitivity would be a pertinent factor (one of which I'm ignorant) with both of the poweramps I tried and the Demmie's internal power. My little A/B/C was hardly scientific -- while I feel confident in my observation of the results, I can't say anything definitive about the cause(s).

What you say about the 1000W Ice is certainly encouraging. I thought it stellar with the BoT, and imagine your amp is even better. What is the input sensitivity of the power-amp you put together, if you don't mind my asking?

It really is difficult to do an accurate A/B comparison without building a power section from scratch with each module and then normalizing to account for things such as input sensitivity. I don't recall the sensitivity/impedance numbers for the 1000 off the top of my head, but it does take some juice to drive - I believe the Hypex units require a good deal less input to be driven to full power. So one might prefer the Hypex to the ICE for that reason, just like the old PLX's (with the lousy input sensitivities) were thought to not be as beefy as the CA9 when in actuality there just wasn't a lot of bass preamps that could drive them to full clip and/or not get loaded down (which can have a lot of negative impacts to the tone and feel). Things get even more confounded when running into the effects returns of heads which is usually mediocre at best compared to a standalone power amp.

The BoT has enough output in the unbalanced out to give you a bit of a zap if you hold the other end of the cable and crank the level, so it will blast anything, and the Studio can drive the module to full output with the gain at 9 o'clock and master at around 1 o'clock, so no issues there.

Other factors - Mike had mentioned that he disconnected the Jensen front end I put in the power amp because he thought it sounded better - and that makes perfect sense because he was using the balanced outs on the BoT and Sonic Farm when he was evaluating. They both have transformer balanced outs, so transformer out plus another one on the input isn't optimal. I liked the sound of the unbalanced out on the BoT feeding the Jensen input of the power section when I was evaluating it rather than the balanced out, so my observations were similar. But with an unbalanced signal feeding the poweramp, I like the Jensen better than just feeding the ICE directly, and my integrated amp uses an approach on those lines. So there are a lot of different things that can and do affect tone and feel that have nothing to do with the modules themselves.

Folks have also mentioned the 250 based modules sounding more ragged/gritty, which may or may not be good depending on what your goals are, but it makes sense since those modules are bridged and each side is running at two ohms (and I believe they are only rated to 2.7 per side), so they are pushing them pretty hard, and in addition to the potential for thermal issues will also be getting higher THD. The 1000 has a flat response in the audible range and has been used in expensive HiFi amps for years now, and is also used in subwoofer applications, so it's not surprising it just coasts along like it does.

So all in all, there are a lot of things that go into it, but I'd expect the 700 and 1000 ICE offerings and the 700 Hypex to all perform admirably if they are integrated properly into one's design. I chose the 1000 because I find anything less than 500 watts at 8 ohms inadequate, and it's a proven, stable design that works just dandy for bass MI applications.

 

[MarkA]

Jonathan,

Thanks for the detailed reply. You've given me a few things to mull over.

Speaking of "500 Watts at 8 Ohms," and since we're in the Big E Speaker thread, Mike, what do you think it would take to drive the 8 Ohm MAS 112 optimally? One the one hand, the 18 Sound driver is supposed to handle being hit with a lot of juice well. On the other, this is a cab that is supposed to do well even with a modest amp. I suppose I'll eventually figure out the sweet spot (and maybe it's erroneous to think of it as a "spot") on my own, but, while we're here...