Help me choose an amp

[EndersShadow]

So here's the deal. I'm fairly dialed in on what I want to buy sub wise.  I'm going with either 2 HST-15 or HST-18's.  Leaning 15's for cost and box size reasons.  The 15's would be in a 3 cubic foot box, while the 18's would be in a 4 cubic foot box.

 

Right now I only have a single Dayton SA-1000 amp so thats not gonna fly.  I have enough SPL on with my Stereo Integrity HT-15 in a ported box, but not enough subsonic stuff, and I want to even out room modes too, which dual subs will do, in addition to providing more SPL.  I'm not trying to do something crazy like 150db, but am looking to be around 100db or more from ~10 feet away in a large open room.  I'm highly debating just buying another Dayton SA-1000 amp to go with either sub as it models decent enough in WinISD for me, but I am wanting to talk to the pro's here about it since I'm not as knowledgeable about DIY as most of you.  My current model assumes a single PEQ filter of +4db @ 25hz w a Q of 1.  That brings things up and provides a decently even response from what I see.

 

Here are the amps series I've already ruled out:

 

Beyer iNuke's.  I simply don't like the fact they require you to mod the fans to be anything close to quiet.

Crown XLS series.  The subsonic filter at 20hz kills what I really want to increase which is my subsonic content.

 

Here is what I'm looking for in my amp:

 

-Budget: Lets say around 400-700 max, open to used, refurbs, or purchases off eBay.  I'd prefer to be closer to 500 if possible as I'm not sure if I can get to 700, at least new.

-Inputs: XLR, RCA (if at all possible)

-Outputs: Speakon, BINDING POSTS (if possible)

-Fans that are quiet within reason.  I realize they will likely make SOME noise, but if its quiet I'm ok with that.  I have a HTPC with 4 120mm fans running about 1000 rpm that are darn near inaudible from where I sit.

-17" width if possible, otherwise 19" works fine, but it will be enclosed with a door covering the front, and with an open back and a somewhat vented bottom section

-Wattage: something with more than 1k x 2 @ either 2 or 4 ohms.  I'd prefer to have the subs be dual 2 ohm subs running at 4 ohms to make for an easier load on the amp.  The wattage I will need is open for discussion, but I've been modeling for each sub to get around 1k in WinISD and that gives me what should be enough SPL for my tastes.

 

So what pro amps would you guys be looking at?  Crest ProLite DSP models, Peavey IR stuff, something else crazy

[lukeamdman]

The IPR/ProLites have noisy fans.  They'd also need a fan mod unless they were stored outside the HT. 

[EndersShadow]

The IPR/ProLites have noisy fans.  They'd also need a fan mod unless they were stored outside the HT. 

 

Crap.  Not a possibility, dont have a fully dedicated HT room.

 

Thanks for the heads up though.

[3ll3d00d]

fwiw the inuke fan mod is no more involved than changing the fan in a PC, just unclip the connector and plug the new one in. I'm not sure there are many pro amps that aren't noisy, it's not a design consideration for them after all.

[EndersShadow]

Yes but then you run the risk of warranty issues if it breaks, you switch it back to the stock fan and they realize it. Especially since the I'd likely add extra heat sinks as others have done as well.

 

I'd rather not have to mod it if possible. I'm capable of doing it (since I build computers and do IT for a living) but would prefer to not have to do that.

[3ll3d00d]

order from Amazon then, they take literally anything back 

 

I can vouch for speakerpower as quiet and powerful, obviously costs a fair bit though. I don't know where else you're going to get >=2kW of quiet power from. One of those dayton plate amps perhaps? http://www.daytonaudio.com/index.php/loudspeaker-components/subwoofer-plate-amps/spa2400dsp-2400w-subwoofer-amplifier-wl-dsp.html(still too expensive but no idea if anything is floating around 2nd hand)

[EndersShadow]

order from Amazon then, they take literally anything back 

 

I can vouch for speakerpower as quiet and powerful, obviously costs a fair bit though. I don't know where else you're going to get >=2kW of quiet power from. One of those dayton plate amps perhaps? http://www.daytonaudio.com/index.php/loudspeaker-components/subwoofer-plate-amps/spa2400dsp-2400w-subwoofer-amplifier-wl-dsp.html(still too expensive but no idea if anything is floating around 2nd hand)

 

Yeah, well the other option besides a stereo pro amp was to just add another Dayton SA-1000 amp since I have one already.  At 4 ohms its "supposed" to put out about 1k @ 4 ohms.  I realize its likely more like 800, but when you double that to 1600 watts and add another sub and box it gives very decent numbers.

 

The SPA models are ones to stay away from as they have undefeatable subsonic filters, where the SA models have a on off switch for them.

[NWCgrad]

Would be nice to get the XLS amp measured. I know the folks at Crown have indicated a 20 Hz HPF is in place, but end users have reported differently. Sadly, manufacturing reps are often wrong - but without solid proof who wants to risk making the purchase. The XLS amps are very quiet.

 

What about a Crown K2 amp off ebay? No fans to make noise and put out 800 WPC into 4 ohm load.

[EndersShadow]

I agree. The XLS was a front runner for quite a long time but I just don't want to risk it with the high pass filter.

 

Thing is I've heard a couple diff versions of the high pass but they all indicate they are there.

 

I've heard it's a 18bd per octave rolloff but some have heard 12, etc.

 

I've got one on hand that's a loaner if someone happens to be local that can measure it lol...

[NWCgrad]

If I wasn't so lazy I would run my XLS 1500 on my sealed 18" sub, could do a nearfield measurement to compare to the QSC RMK 1850HD amp which is known to be flat to under 10 Hz (-3 dB at 5 Hz per the manual). Data trumps all.

 

Made correction to previous post, it's the K2 amp that is fanless.

[chrapladm]

"I am my own warranty," has always been my motto. So just buy an Inuke:D

 

I bought y pair of Crest amps 7 years ago and modded the fan so they were silent. I sit about 6ft from them and have never had any problems. Forums are always a huge help on most anything electronic. SO dont worry about a warranty and buy what you can afford. If you want to spend SP type money then warranties are nice. Just my 2 cents. For my eventual pair of subwoofer cabinets I will be using either a SP12K or Bosso's amp if it is available.( dont know if it will be available when I finally have the funds)

[dgage]

The SpeakerPower is hands down the best sub amp I personally know of but it isn't inexpensive. I'd like to disclose that I sale said amp but I felt that way before I started my business and nothing has changed my view.

 

Since I'm often asked for a DIY amp recommendation, my go to is the IPR2-7500 or the sister amp Crest Prolite 7.5. Fan mod likely needed in your case.

 

I'm not familiar with Bosso's new amp but that sounds like a beast and is cheaper than the SpeakerPower.

 

I'd also like to point out that I have my HST-18s in an enclosure just slightly larger than 3 cu.ft. and it works well with a little DSP. So you could have your cake and eat it too if you wanted to go big AND small.

 

Regarding the Dayton, I really don't think even two would be enough power to make the HSTs really sing. I remember when I went from 2400w to 4000w on my previous LMS-5400s, the difference was very noticeable, another level of performance.

[Shredhead]

Please don't buy a Dayton amp.  It would be a quite waste of time to try to power an HST with one of those especially if you are going to use an EQ boost down low, not to mention they are high passed so they don't explode. 

[EndersShadow]

Please don't buy a Dayton amp.  It would be a quite waste of time to try to power an HST with one of those especially if you are going to use an EQ boost down low, not to mention they are high passed so they don't explode. 

 

The amp I am looking at specifically, the SP1000 (not the SPA1000) has a defeatable subsonic filter.  I have modeled it in WinISD and with the boost mentioned above via PEQ and nothing else, the VA in that program is listing the actual usage never hits 2k (combined output of both per spec's).  

 

Other than that defeatable filter there is no highpass according to Dayton directly.

 

I'm not saying thats what I want to do, but I also dont have 1-2k to throw at some of the more pricey amps.  I realize that with 1000 watts per driver I am leaving some excursion on the table and not fully using all their potential, but I simply wont ever be able to afford an amp thats got enough nuts to power them right.

 

The other factor here is that you can only pull so much from a given circuit and I DONT have a dedicated circuit for my different HT stuff.  So on this same circuit I have my living room lights, ceiling fan, 5 channel dedicated amp, avr, 3 source components, Panasonic TV, etc.  So there is a good chance if I try to PULL a really large amount of wattage from the wall I will trip the circuit.  And while I'd love to add one or two or three for my HT, its positioning on the opposite end of a house on a slab from the breaker would make it to costly to add in the short term.

 

Also my wife is not a huge basshead like me, so running the subs at full gain will not happen often if ever, so all more power would give me is a smaller gain knob window to adjust from no bass to too much bass .

 

If the XLS series amps were an option, I'd just try to go for 2 XLS 1500's or 2000's with each one bridged and running one sub on it, but that 20hz highpass I keep reading about just makes the amp pointless.  The iNuke's again I'd prefer to not have to screw with replacing the fan to make them quieter (and lets be honest they are FUGLY).

 

The Crown K2 amps look intriguing and the fact there is no fan is a plus (I'd probably add a laptop cooler on top of it to help cool it).  Would those amps be a decent option for the HST's?  I'd probably try to get 2 units so I could bridge each one, but again I'd likely be tripping a circuit before using all the wattage they could provide.....

 

I appreciate your guys thoughts on this.  Again not a strong point of mine in the audio stuff...

[EndersShadow]

The SpeakerPower is hands down the best sub amp I personally know of but it isn't inexpensive. I'd like to disclose that I sale said amp but I felt that way before I started my business and nothing has changed my view.

 

Since I'm often asked for a DIY amp recommendation, my go to is the IPR2-7500 or the sister amp Crest Prolite 7.5. Fan mod likely needed in your case.

 

I'm not familiar with Bosso's new amp but that sounds like a beast and is cheaper than the SpeakerPower.

 

I'd also like to point out that I have my HST-18s in an enclosure just slightly larger than 3 cu.ft. and it works well with a little DSP. So you could have your cake and eat it too if you wanted to go big AND small.

 

Regarding the Dayton, I really don't think even two would be enough power to make the HSTs really sing. I remember when I went from 2400w to 4000w on my previous LMS-5400s, the difference was very noticeable, another level of performance.

 

Thanks for your thoughts.  The main reason go with 4 cubic foot boxes is that the flatpacks in that size are setup for the 18" Stereo Integrity drivers, and the 3 cubic foot boxes are setup for the 15" Stereo Integrity Drivers.  I'd have to tweak the 3 cubic foot baffle to fit the 18" and I'm not exactly super handy with tools, or even own them to try my hand at the tweaking.

 

I am very well aware of the speakerpower amps, and they look AWESOME, but as you mentioned, they are a few leagues outside my budget, otherwise I would just buy two and be done lol....

[Bossobass Dave]

Sealed subwoofer performance is directly related to and completely dependent upon...

 

AMPLIFICATION.

 

I've built and operated more sealed subwoofer models in 3500 cubes over the past 15 years than anyone in this dimension of our solar system. I've used all of the QSC RMX models as well as the Crown XLS. I have the Marathon 5KW amp and the American Audio 6KW amp (100 pounds, 3RU big iron beast). I was the first AVS user of the Sanway LG copy amps and recommended them to notnyt. I've used 7KW, 9KW, 12KW and 14KW versions of that platform from a half dozen Chinese agents and manufacturers. I've tested various Class D amplifiers, with and without on board DSP, all of which have been rackmount amplifiers with commensurate cooling fans.

 

The A Series amplifiers are the best value power for a sealed EQ'd subwoofer system I'm aware of.

 

To our GTG, Nick brought a pair of HST-15s. Without signal shaping, they, like any other sealed subwoofer, perform well but nowhere near optimally. After dialing in a proper response using the Marchand Bassis, the in-room response was world class.

 

 

We used an A-9K amplifier and played the cop car scene from HULK and progressively bumped the output power until we pushed the HST-15s to a measured 45 mm one-way throw. The measured output power was 8900 watts peak (the A-9K is rated to 9000 watts peak, bridged into a nominal 4 ohm load). The mains connection was a dedicated 120V-60Hz 30A outlet which technically will output 3600 watts continuously, but obviously peak voltage output of the A-9K on that outlet is a few decibels more.

 

The 2x15" HST Raptor module required a +6dB low end boost in the signal to achieve the results we measured at the listening position. That means that if we run the sub at a nominal 2000 watts with content >20 Hz, we required 8000 watts for transients that include content <20 Hz, as the scene in HULK and many, many other scenes do. The HST-15 has a measured sensitivity of 85dB 1W/1M. A pair of them in a single box would yield 88dB 1W/1M. To see a peak result of 120dB at 1M would require 2000 watts input power.

 

If you cut the power plant capability by -3dB, that would be a cruising power consumption of 1000 watts with full bandwidth peaks of 4ooo watts. That (4000 watts peak) is the minimum I would use. The A-5K would be perfect and have a dB or so headroom.

 

You can eschew signal shaping and use a lesser amplifier but then I would recommend also buying lesser drivers and saving the money you would be wasting by applying crap power to world class drivers. That's why we call them Systems.

 

The SP amplifiers are wonderful products from a great engineer through very cool dealers. They deliver the goods and are quiet in doing so. On the down side (every piece of hardware has one) they're butt-ugly, they're monoblock or dual bridged only and cost double the price.

 

The rest of the choices mentioned will be the wrong choice for any system utilizing HST-class drivers and the Dayton stuff is for children under 10 years old.

 

Just my opinion, FWIW, YMMV.

[EndersShadow]

Thank you for the explanation and the graphs.

 

So if I were to be starting from scratch with a budget of say 1500 dollars for a dual sealed sub system, what would you suggest?  Box size cant be bigger than 4 cubic feet and 3 would be preferred.

 

Budget would include amplification and the knowledge I'm just working off a 15 amp shared circuit.

[Shredhead]

I'm not buying that this does 1000W.  That heatsink looks undersized for as many transistors are on it with no fan to cool them.  That alone makes me question the response of this unit.  The designers would most likely put a good amount of rolloff on the low end to protect from overheating.  I'd be surprised if it was much different in response than the Crowns. 

 

I agree with Bosso, if you're going to go with an amp of this caliber maybe a cheaper, lower xmax, more efficient driver is the best solution?

[EndersShadow]

Shred I'm not smart enough to argue but I would like to mention that compared to the iNuke the heat sinks in these are massive.

 

I'm also not modeling it as a full 1000, my WINISD models are based on it providing 800 watts.

 

I will say it gets decently warm hence having it in a area that's open on the bottom/top/front/back.

 

I also think it uses the case to help radiate heat.

 

Again I'm not against other options I just don't have a ton to spend on amplification alone.

[Shredhead]

Please don't take it that I'm arguing about this, I'm just riffing here.  The heat sinks can be much smaller if you force air cool them.  Also the inukes are class D which can get away with smaller sinks than class A/B.  I've seen 400W class A/B amps with larger sinks than the SA1000 that were passive cooled.  I just think Dayton amps aren't a very good value that's all.

 

I understand you're on a budget Ender and if you end up with another Dayton, I won't really mind all that much as long as you're happy.  Just chipping in my 2 cents for what it's worth.   

[EndersShadow]

I understand your just trying to make sure I understand the implications of the parts I buy. And since that was the purpose of this post I do sincerely appreciate it.

 

I forgot the iNuke was Class D and this wasn't. Personally I think this amp design reminds me of some of Bob Carver Sunfire True Sub juniors with the tracking down concerts and whatnot. But I'm not smart enough to understand how all that works .

 

I am looking hard at some of the other amps folks have suggested to see if they can be had witching my budget. The suggestion by Bosso for the A5k I'm guessing is a custom amp as I can't find it anywhere.

 

The Crown K2 is interesting and provides a very decent amount of wattage. Would this amp suffice info were to eventually end up with two?

 

I could afford one of the HST drivers a flatpack and an amp. Then later on another driver and flatpack once my current sub and amp sell and the maybe another amp later on after I clear out some more gear.

 

So would a single HST-15 do decent with the K2?

[chrapladm]

Going off of memory the K2 would be a good amp for a lesser class subwoofer. I have learned quite a bit over my 10 years of building subwoofers and all this has taught me that you should buy once and dont skimp out because of budget. This sort of goes with everything in life. I almost never have any savings and it takes me for ever to do a subwoofer build but who cares. I would suggest modeling what you want SPL wise and then buy the proper amplifier. 

 

Take your money and buy the biggest amp you can. As I said I will most likely be buying Bosso's A14K if it is available. I will only have a single pair of 15HST's. Then when I can afford it I will buy some more subwoofers. But for me this will be four total 15HST's. There are better budget friendly drivers out there if you really need to save. Buy what you simulate and fits your needs. Then just save until you can afford it.

 

The bad thing about these forums is that so many great products keep coming out and wanting me to sway my opinion. Nick's new DS4 18 when it comes out would be cheaper than the 15HST's but I cant look at it like that.

 

Anyways if buying HST drivers I would suggest the A5K if you can find it or Bosso's amp if available. Or if you have an amp already then just use what you have and save for the bigger amp. I would have bought a cheap Inuke to get me buy but I have a hard time buying anything from Behringer. Crest, Crown and QSC for me for mains and Bosso/SP for subs. I am sure the Powersoft amps are awesome but those are even more money.

[lukeamdman]

I've only read excellent things about the Crown K2 amps, but aren't they a little dated?

[dgage]

What about buying a Peavey IPR2-7500 ($700-$800 on eBay, http://www.zzounds.com/item--PEVIPR27500?siid=124608),a single HST18 ($535), and the flat pack?  This would be within your budget and would give you some solid bass and would allow you to add additional subwoofers to the single amp.

 

With the single IPR2-7500 you could run either 2 HST-18s or 4, depending on whether you want to give them a solid 2,000w or over 3,500w per sub. 

 

And I'm not necessarily recommending buying the amp from eBay but that gives a good idea of where some dealers might be willing to sell the amp if you call them.  I also linked to a blemished unit that ZZounds has for sale but I've never done business with them.

[EndersShadow]

What about buying a Peavey IPR2-7500 ($700-$800 on eBay, http://www.zzounds.com/item--PEVIPR27500?siid=124608),a single HST18 ($535), and the flat pack?  This would be within your budget and would give you some solid bass and would allow you to add additional subwoofers to the single amp.

 

With the single IPR2-7500 you could run either 2 HST-18s or 4, depending on whether you want to give them a solid 2,000w or over 3,500w per sub. 

 

And I'm not necessarily recommending buying the amp from eBay but that gives a good idea of where some dealers might be willing to sell the amp if you call them.  I also linked to a blemished unit that ZZounds has for sale but I've never done business with them.

 

Thanks, that might be what I have to end up doing.  I'm more likely to run the amp as a 4 ohm load than 2 ohm so it doesnt have to work as hard, which should also hopefully mean the fans dont come on as often.

 

While its rated for 2 ohm loads, I just dont know if I would trust it to run that load 24/7 365.

 

I had simply hoped to be able to run dual's on that budget but it seems the only way to do that is to go with a less expensive driver, which then likely means not as much ability to boost and EQ the low low end to increase the SPL under 20hz which is what I was hoping to do.