Plate Amp for Sub

jakelm

I kind of through this subject in, in another thread, but decided to start a new one here, for all you DIY'ers.

I was wondering about plate amps for subs.

I currently have a vintage Hafler-200 amp (approx 160 watts per channel @ 4ohms). I have a Dayton 12" DVC 4ohm in a 3.7cuft incloser with a 3" x 11" long port, tuned to approx 24hz. I bought an SVS 12.1 , that should come in anytime now to replace the Dayton. I was looking into Bash amps, particularly the 300watt Bash amp at parts express. I have the Hafler on the sub right now, but was going to put the Hafler on my vintage Polk 7b's and buy a plate amp for the sub. Is this 300watt bash amp a similar bash amp that SVS uses? What are the pros and cons in going from a straight up Hafler amp to a plate amp? What also interest me about the plate amp is the fact that I can custom the bass boost. Is this worth the effort? Or should I just keep the Hafler on the subs?

Thanks
Jake

jakelm

Or even this, http://cgi.ebay.com/225WATT-EOSONE-POLK-1RF0036-1-SUBWOOFER-PLATE-AMP-NEW_W0QQitemZ280062542762QQihZ018QQcategoryZ67786QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Polk Eosone plate amp. But I think the bash 300watt would be alittle better being I can easily change the bass boost. Right?

Jake

ohskigod

I've used a regular amp as well as plate amps on my DIY sub. I just get better results with plate amps. you can tweak the level, phase, etc etc. allways got better results with the plate.

is that 12.1 a plus driver, if so, you might want to look at the 500 watt jobby from parts express, mine craves nearly every watt of it. but if budget only dictates the 300, it will still kick arse I'm sure.

if it is the ISD, then 300 should more than do. I have no experience with the bash amps, but I had the 250 watt plate amp that preceded it (looks to be no longer available since parts express started selling the bash amps) so I imagine the bash amp being as good or better. I would go plate amp on it IMHO

ohskigod

by the way, is that 3.7 cu ft. box ported or sealed?

my box is very similar in sixe to the PB12+ single driver sub, so when I got the driver (originally had a shiva), I knew it would probably fly.....and boy was I right.

I dont know about an SVS sub in a smaller sealed box though, might not be a good match


*****you allready mentioned it was ported, I'm a schmuck ********

jakelm

ohskigod wrote:

is that 12.1 a plus driver, if so, you might want to look at the 500 watt jobby from parts express, mine craves nearly every watt of it. but if budget only dictates the 300, it will still kick arse I'm sure.

It is a plus 12.1 driver. And no my buget isnt set on the bash 300. I could get the 500 watt but I just didnt want to spend what i didnt have to.

Jake

jakelm

ohskigod wrote:

by the way, is that 3.7 cu ft. box ported or sealed?

It is ported, to about 24hz. Was just wondering how well this bash would work compared to my hafler.

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=300-750


or this one if needed.

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=300-752

jakelm

And like I said, the fact that I can control the bass boost interest me. Or is the fact that you can teak the bass over rated and a sales gimmick?

jakelm

I guess i'll get the 300watt, since I'm using a 12.1 plus svs driver. And 300 watts should be plenty for the SVS. It looks like the +4dbs are a multiple of 3 for every octive, so in my theory I could put for R26=21kohms an R25=210kohms and get a bass boost of +4 for around the 18-22hz. Am I close? Or would that put too much of a strain on the amp?

Jake

Systems

The BASH amps look like great units for the money.They have some very useful features that allow you to tweak the response and the HP filter can be customized to supply boost or set very low to limit excursion so as to protect the driver from bottoming.The task of integrating a sub with the mains can be tricky but the phase control and variable crossover will be very benificial in getting a good blend with your main speakers.The BASH units are quite powerful l and being a Class D they run cool.

jakelm

The SVS plus driver from SVS is used with a Bash 500 watt. I'm still wondering if this 300 watt Bash (besides the wattage) is pretty much what SVS uses?

Jake

Systems

I think the BASH units SVS use are very similar except they don't have the HP filter.

jakelm

Is there a way to take out (or bypass) the Hp filter completely in these amps? Since SVS doesnt use a HP filter. I'm using a SVS sub, I would like to get as close to the specs as possible to SVS.

Systems

Yes it is possible to completely bypass it.But I would leave it in because if you just set it to the lowest frequency and lowest boost it's presence will likely go unoticed and it will provide some protection from over excursion when playing source material with heavy bass content.

jakelm

Well the reason I ask is because my Hafler-200 is just a straight up amp. And seems to be doing ok, without a Hp filter. Unless it has one and I dont know about it.

Jake

Systems

No the Hafler won't have a filter.But like I mentioned in my previous post the HP filter can be benificial because it will help protect the driver from over excursion at very low frquencies.( below Fb or tuning frequency).

ohskigod

here is the one I use with the same driver

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=300-806

its quite a bit more scratch than the 500 watt bash, and i have no idea which is better (the Bash was not available when I bought mine on sale at 199.00)


the bash seems to be on sale and at a damn good price for the power. I just never laid ears on it, but in your position, I would probably get the bash. I've never been a fan of bass boost though.

rule out the 300 watter, I got 500 going to mine in a bigger enclosure and it loves the power, so in a smaller enclosure, that power will be needed even more, not a lot more, but more. my .02 = hell no on the 300 watt option.

jakelm

Just an update:

I bought the Rythmik 350 amp. What a great and powerful amp.

I increased the size of my port from 3" to 4", still in the 3.7cuft incloser. I found less port turbulance with the double flared, 4" port. Also the length of the port from 11" to 18". The bass is fantastic. VERY deep and musical.

I have always been a big fan of 2 subs, to take care of any nulls in the room, but with the Rythmik amp and the SVS driver, the nulls are gone. I dont know how, but oh well....

I am ordering the 24db chip from Rythmik. The 12db slope that comes stock is just not fast enough. I'm still getting crosstalk with very deep vocals. I'm hoping the 24db slope and setting the Lp crossover on the plate amp to 40hz, will take care of that.

The one thing I like about this amp, is that fact that you dont have to solder or make any adjustments to the circuit board itself (unless changing the slope from 12 to 24dbs). The amp has toggle switches to adjust the Hp (rumble) filter. I have mine set @ 14hz-med dampening. Which is giving me a pretty flat responce down to 18-19hz (+/-2dbs). Which is the closest I have ever had.

My H/K 635 AVR is set @60hz, size = 15". Now I know that it is not recommended to use both AVR and amp crossovers, but when running the EZEQ , I dont want the AVR to think the Fr has to go up too 120hz, I found it gives a boost to the Fr the the sub has "lack of". And the size you put in the AVR does make a difference, since the AVR has a Hp filter. 12" = 20hz Hp....15" = 15hz Hp. So I set it to 15" and let the plate amp do the rest.

But anyways. I want to give a nodd to SVS and Rythmik audio. What a fine match they make, even in my DIY incloser.

Systems

That Rythmic looks like a great amp and I also prefer the steeper 24db LP filters on my subs.