help choosing a 7" mid

Status
Not open for further replies.
Jump to Latest
3

300Z

Member
Joined 2006
s24.photobucket.com/albums/c31/CorradoVR6z/
#1
help choosing a 7" mid

Hi all,

I want to build a new set of nearfield speakers and i need some help find the right mid...

Right now i'm using Vifa PL18 (4ohm version) mated with a Dayton RS28A tweeter, using just a simple LR4 x-over at 1.6khz.
Before the PL18's i was using the Dayton RS180-8 mids and i liked the midrange on the RS180's a lot but the midbass lacked impact/attack and snap, it had the output but it just lacked impact.
While the PL18's have a bit better midbass impact it's still doesn't sound quite right but the real problem with the PL18's is the midrange sounds "hollow" and lack the detail from the RS180, with some EQ help i got to shape the FR to a somewhat smooth response and it does sound better but the detail just isnt there... 🙁

I have been looking at these drivers and since i can't go out and listen to all of them i would like to know what you all have to say about them...

18 Sound 6ND430
Seas L18RNX or P18RNX, but i'm not sure about those...
Aura NS65, low efficiency...? 🙁
B&C 8PS21 not a 7" but i think i could manage to fit it...
Or just go back to the RS180, but thinking of getting the 4ohm version instead this time around, and just live with the wimpy midbass? 😡

The new mids will be mated with the Dayton RS28A tweeter and inicially will be powered by a SI-T amp but i'll eventually going to get a Crown XTi-1000 amp.

Also, just in case, my listening position is only ~3-4 away from the speakers if this going to matter.
And i don't necessarily need very low end extension, if can get it to play down to ~60hz that should be enough, i can just let the subwoofer pick up from there...

Thanks a bunch and sorry for the long post, I hope i provided as much info as needed.

Leo
 
#4
No wimpy bass here.
These DA175's from Dayton will literally put a hole in your chest or try to. Best bass I ever heard and felt.
http://www.partsexpress.com/pe/showdetl.cfm?DID=7&PartNumber=295-335

I'm currently finishing up two projects with them drivers and here is a pic of one of them - "The Quads";
driverlayout.gif


These also tested well at 'Zaph';
http://www.zaphaudio.com/6.5test/

So no worrys on distortion.

I'm using North's D25 tweeter's but there is crossovers for;
Seas 27tbfc and 27tdfc
North d25's
Vifa Neos
and the HI-Vi K1...
 
#5
I've read all the tests from John K (Zaph) and Mark K...

My problem is not with output, all the drivers i used had good output...
I had 180w for each of the RS180's and have played with the PL18's running on 320w each and it had all the output i could ask for; but tonaly both just didn't seem to sound quite right on the midbass department...

At higher levels the PL's seems to hold itself better than the RS180, it seems more dynamic while the RS180 seems compressed... 😕

Leo
 
#6
Before the PL18's I was using the Dayton RS180-8 mids and i liked the midrange on the RS180's a lot but the midbass lacked impact/attack and snap, it had the output but it just lacked impact.
Click to expand...

That's what I'm talking about. 🙂
The snap and attack come from the 80 to 120 hz. range. These Daytons are also smooth in the upper mids.

I also have the RS 180's & RS 225's and the bass seems to hit me like a medium-hard pillow. With the DA series they have that 'Whack'..
It makes the drums sound extraordinarily good.
 
#9
#10
Yes, paper cones with high effiency motors!
Most excellent for reproducing electric guitars but they just don't have that Whack and feel of the Dayton DA175 for drums and bass guitar.

So marry the two, hence my next project.
A line array with the B&C in the middle of the array surrounded by 8 DA-175's. Mids might be RS52's with a line of 50 - 60 Dayton 3/4" Neo Tweets.

Yep, I'm a speaker nut. Been there, done that but just not quite there.
 
#11
Both the B&C and the 18 Sound aren't just your average high efficiency midwoofer. They both have more excursion than the DA175, more cone area and copper shorting rings in the motor for reduced distortion...
They may not play as low as the DA175 but i'm not too worried about low end extension as long as they can play into the 60hz range...

I just need a MT alignment... 8 midbass per side is just overkill for my application... besides i don't even have the room for it. I don't listen to my music at loud levels...

My listening room is small... at only 11' x 12'.

Leo
 
#15
Why is this thread now 15 posts long and no one has asked about the enclosure LOL?
Sure, BSC and generic XO's will factor in, but my prime suspect would be the box.
Sorry Rudy, the DA175 in a very nice unit for the $, but if one is getting better sound out of them than the RS180, check one's design skills - rather than the commonplace "blame the driver, room, XYZ first" methology popularized on message boards.

cheers,

AJ
 
#16
AJinFLA said:
Why is this thread now 15 posts long and no one has asked about the enclosure LOL?
Sure, BSC and generic XO's will factor in, but my prime suspect would be the box.
Sorry Rudy, the DA175 in a very nice unit for the $, but if one is getting better sound out of them than the RS180, check one's design skills - rather than the commonplace "blame the driver, room, XYZ first" methology popularized on message boards.

cheers,

AJ
Click to expand...

The poster doesn't appear to be new to DIY speakers and since he didn't ask about enclosures specifically . Also, I'm assuming a ported alignment here. IMO most ported misdesigns suffer booming bass and that did not seem to be his issue. Lack of BSC seems to be most prevalent in intermediate design Q's.
As always YMMV


<edit> Maybe a misdiagnosis but the symptoms were there.
 
#17
doesn't appear
Click to expand...

I'm assuming
Click to expand...

Correct.
But I'd rather not assume.

Lack of BSC seems to be most prevalent in intermediate design Q's
Click to expand...
Ok. Infinia, I can't say for sure that it is his enclosure/tuning, but you seem to have given this quite a bit of deep thought, so I'll ask:
At what frequencies are his baffle diffraction losses occuring based on his enclosure size?
How much BSC should be built into his filter based on his enclosures distance from the rear wall?
Why is the active EQ
with some EQ help i got to shape the FR to a somewhat smooth response
Click to expand...
failing to do what a passive shelving filter would?
What is it about lower on axis SPL in the bass region that makes
the midrange sounds "hollow"
Click to expand...
Thanks in advance.

cheers,

AJ
 
#18
Ok now it's getting better... thanks guys... 🙂

I'm not exactly new to audio in general, but at this point in time i just dont have the equip to do my own testing and design.

The speakers that i'm using now was just thrown together using parts that i had laying around. I know this isn't a good start but i needed some tunes... 😛

The box is a ported alignment, .55cu.ft tuned at 43hz as far as i remember...

My problem is not with actual output. But with overall tonality.
My SI T amp isn't modded... I just got it as a temp amp solution, I should be getting the Crown amp i listed within the next month or two.

The speakers sit on my desk and are ~3' away from the wall.

EQ is used mostly to take care of FR irregularities due to the lack of filter contouring... 😛 🙄

Before i built the passives that are in use now, i used an active x-over to find the wanted cut-off freq...

As i said, my main problem is tonality, and midbass impact/snap...

The speakers don't sound outright bad, but just not up to my standards... just me being picky... 😀

I hope i provided enough info this time... 😛

Thanks
Leo
 
#19
Sorry Rudy, the DA175 in a very nice unit for the $, but if one is getting better sound out of them than the RS180, check one's design skills - rather than the commonplace "blame the driver, room, XYZ first" methology popularized on message boards.
Click to expand...

No disrespect AJinFL this posters primary question was getting some 'Slam' from a midbass driver.
Since I'm a fan of both the RS drivers and the DA series and having to listen to them for over two years the 'Slam' award goes to the DA175's.

Since I don't like ported enclosures they're out....
Sealed, Transmission line are fine with me.

Also my design skills with the RS series fall on the shoulders of Jon Marsh & Darren Kuzma.
The Da 175's are a combination of Pete Schumachers (crossover) and mine ( the box).
 
#20
RJ said:

this posters primary question was getting some 'Slam' from a midbass driver.
Click to expand...

Midbass lacks "snap"... 😉

At first i was just going to build Jon Marsh MT design using the RS180, but after playing with the RS180 in an active setup for a little over a year i'm not so sure sure i want to go that route again... I liked the midrange, but the lack of midbass snap just didn't cut it for me... 🙁

Leo
 
Status
Not open for further replies.
Top Bottom