Amp for VMPS Larger Sub?

Xi-Trum · « **on:** 24 Oct 2003, 02:01 pm »

I thought I saw this question brought up before. But I couldn't find it using the Search feature. So I ask again.

What would be a good amp for driving the VMPS larger sub to the fullest. I'm looking for something that is quiet, ie. no fans. I may eventually get another larger sub, so stereo amp is a plus. Price range is about ~$1k.

Thanks.

Marbles · « **Reply #1 on:** 24 Oct 2003, 02:04 pm »

Crown K2 used on Ebay for $800-900

Tyson · « **Reply #2 on:** 24 Oct 2003, 03:12 pm »

Agreed on the K2, really good amp.

Xi-Trum · « **Reply #3 on:** 24 Oct 2003, 03:28 pm »

Thanks, guys.

Tyson, how's the K2 compared to the QSC that you've heard? I try to stay away from the QSC due to fan noise. Thanks.

Sedona Sky Sound · « **Reply #4 on:** 24 Oct 2003, 03:59 pm »

If you want to go the used route, then you have lots of options for older high current amps. I noticed an Aragon 4004 on Audiogon for $750 that should be perfect (especially if you live up north and need something that can double as a space heater

). Some of the older Classe amps also do wonderfully in either stereo or bridged mode. I use a bridged Classe DR-10 in my demo room and have no complaints.

As for getting a stereo amp so that you can use it with a second Larger, this is something I would not recommend. You will likely be much better off giving each Larger their own amp. Since low basss is typically in mono (i.e. LFE), then you will drain both capacitor banks at the same time. Most power supplies will not have the umpfh to keep up which will quickly lead to distortion/clipping. If monetary constraints requires that a stereo amp be "shared", then hook one side to the Larger and the other to a rear or side speaker. That way it is much less likely that the amp will be fully drained at any one time. That being said, the more current/watts you can give the Largers, the better. Plan on a minimum of 100 high-current watts per channel (i.e. minimum of 200W per Larger).

Best of luck.

Julian
www.sedonaskysound.com

ribit · « **Reply #5 on:** 24 Oct 2003, 04:24 pm »

I have been using the ZR 1600 in bridged mono mode with great results.

Randall

covermye · « **Reply #6 on:** 24 Oct 2003, 04:50 pm »

QSC PLX 2402 bridged on a Larger here. I ran it in 2 channel mode, one channel to each driver, initially, becuase I was afraid of losing damping factor when bridged. However, after I finally bridged the amp on both speakers, I've gotta say it's even more impressive. I lost no control and seems to have UNLIMITED power for the sub.

rosconey · « **Reply #7 on:** 24 Oct 2003, 05:10 pm »

odyssey monos for mine

Horsehead · « **Reply #8 on:** 24 Oct 2003, 05:49 pm »

I use the Crown K2 with great results. I use the internal "Y" switch on the K2 and send 500 w/ch to each driver on the New Larger. Each driver is then rated at 8 ohms, rather than strapping them together for a single 4 ohm load.

If you can scrape up another $400, Parts Express has a great price on a brand new K2 with free shipping.

http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=245-415&DID=7

flintstone · « **Reply #9 on:** 24 Oct 2003, 07:57 pm »

When I bought my Supertowers a few years ago, I drove them with an Onkyo M-504 power amp (the large sub is pretty much the bottom half of the Supertowers). It has more than enough power for the job (330 watts per@4 ohm load). I now drive the Supertowers with a Krell amp and use the Onkyo on a Vmps sub. It has huge power meter for each channel and is never under strain with the Supertowers or the sub.

You can find this amp for about $300-$400 on audiogon or E-bay.

Dave

Xi-Trum · « **Reply #10 on:** 24 Oct 2003, 08:55 pm »

Thanks for the suggestions, guys. Keep them coming.

Forgot to mention some critical things. I already have the Ampzilla driving the Rm40. I'm using the Bent passive preamp. Mine has two sets of outputs. I want to connect the second output to the bass amp. Hence, I need the bass amp to have at least the gain of the Ampzilla (32dB). Also, I need the amp to have high input impedance.

Ok, I looked at the K2. It has 10kOhm input impedance. That would be too low for the Bent to drive in parallel.

I'll look at other suggestions to see if they meet my requirementss.

Thanks a bunch.

doug s. · « **Reply #11 on:** 25 Oct 2003, 03:02 am »

Quote from: Xi-Trum

Thanks for the suggestions, guys. Keep them coming.

Forgot to mention some critical things. I already have the Ampzilla driving the Rm40. I'm using the Bent passive preamp. Mine has two sets of outputs. I want to connect the second output to the bass amp. Hence, I need the bass amp to have at least the gain of the Ampzilla (32dB). Also, I need the amp to have high input impedance.

Ok, I looked at the K2. It has 10kOhm input impedance. That would be too low for the Bent to drive in parall ...

yure gonna run the sub full range?!? how's this set-up gonna work?

i tink what ya *really* want is only one of yer bent's outputs feeding signal to a nice active x-over, hi-passing to the rm40's ampzillas, & lo-passing to any decent solid-state subwoofer amp of yer choice. pick up a nice marchand x-over for $300-$600 new/used, & spend the remainder on an amp. to be honest, i tink you'll have a hard time finding any s/s amp for $400-$700 that *won't* adequately drive a larger vmps sub. and, this way, gain-matching of amps is not an issue - the x-over will do this.

i had great results w/adcom gfa555's driving my pair of larger subs, (these amps sounded better in stereo than bridged, btw. w/someting like these, do as was mentioned above, & use each stereo channel on each separate driver.) and i am presently using a pair of electrocompaniet aw75dmb's to good effect. the ec's have less than half the wattage rating of the adcoms, but more than four times the current rating. the ec's are really overkill, tho, imo - i only used them cuz ec's were my main monitor amps before i went to tubes, & i had 'em. someting cheap like a used adcom, bryston, onkyo, pro-audio amp, etc, should be more than fine.

doug s.

Xi-Trum · « **Reply #12 on:** 25 Oct 2003, 12:30 pm »

Well, forgot to mention another thing. The sub has a low-pass filter, so it won't be running full range.

flintstone · « **Reply #13 on:** 25 Oct 2003, 01:24 pm »

Are both the outputs on the Bent unit of the same type, also..the Bent will see combined input impedance of the two amps as half. How will you level match between two different amps? Maybe an int. amp for the sub would work.

Dave

doug s. · « **Reply #14 on:** 25 Oct 2003, 05:21 pm »

dave,

xi-trum wants a sub amp w/same input sensitivity as his ampzillas, so the levels will be the same...

xi, disconnect the built-in passive x-over, go active - much better results. the rm-40's will perform better if hi-passed at 40-60hz... most *any* monitor will benefit from this, which is which i would always recommend a quality active x-over for subwoofing... for yer money, a good x-over & relatively cheap amp will give better results than a $1k amp, imo...

doug s.

Marbles · « **Reply #15 on:** 25 Oct 2003, 06:03 pm »

Quote from: doug s.

dave,

xi-trum wants a sub amp w/same input sensitivity as his ampzillas, so the levels will be the same...

xi, disconnect the built-in passive x-over, go active - much better results. the rm-40's will perform better if hi-passed at 40-60hz... most *any* monitor will benefit from this, which is which i would always recommend a quality active x-over for subwoofing... for yer money, a good x-over & relatively cheap amp will give better results than a $1k amp, imo...

doug s.

Doug, these are monitors in name only, and not your usual standmount monitor....they are rather large floorstanders and are -3 db at 25hz. They also hand off to the midrange at 166 hz!

Surprisingly, the bass of the un-eq'ed 40's is more impactful than that of my EQ'ed SVS Ultra's on music (not HT).

XI, have you taken frequency responses of your 40's at your listening position? I'm curious if you sit in a bass null area. If you just push your speakers closer to the wall does the bass get better? Good luck, it's always tough to get everything just right.

doug s. · « **Reply #16 on:** 25 Oct 2003, 06:15 pm »

marbles, i am aware of the rm-40's bass capabilities. certainly not at all surprised that they outperform the svs' on music. but, since even brian cheney told me the rm-40's would be inproved by actively crossing them to larger subs, i believe him!

personally, i'd wager that crossing over the rm-40's would allow more putty to be removed from their passive woofers, allowing for greater upper bass slam, w/o the total presentation getting too bloated, as the fine-tuning for low bass would be done on the larger subs..

doug s.

oh - one other ting - i'm not sure i'd even bother with subwoofing the rm-40's, unless i could run a *pair* of subs, not a single sub... unless, xi, ya wanna run yer single sub in the *back* of the room, outta phase, w/the rm-40's run full-range...

flintstone · « **Reply #17 on:** 25 Oct 2003, 06:39 pm »

I guess what I should have said is, If the two outputs of the Bent are different...one rca and one xlr as mine is, you will not be able to use them at the same time without use of a transformer to break the ground.

If you hook up both RCA and XLR's at the same time you'll ground pin3 of the XLR via the RCA' outputs ground connection - less than ideal for the ballanced connection!

Not sure how his passive is setup as to output types.

Dave

tkp · « **Reply #18 on:** 25 Oct 2003, 09:17 pm »

Quote from: flintstone

I guess what I should have said is, If the two outputs of the Bent are different...one rca and one xlr as mine is, you will not be able to use them at the same time without use of a transformer to break the ground.

If you hook up both RCA and XLR's at the same time you'll ground pin3 of the XLR via the RCA' outputs ground connection - less than ideal for the ballanced connection!

Not sure how his passive is setup as to output types.

Dave

Xitrum's Bent unit is wired for single ended input and output only with dual output for biamping purpose.