Quasi-active and sensitivity

[Why So Cereal? 5,000+ posts]

I'm looking to setup a quasi active front stage. I have midbass covered already and they will be playing up to about 300hz. I'm looking into the Dayton 2nd order Passives crossed at 4.5khz. The first mid that came to mind was the dayton rs100-8. Being fullrange it would have no issue playing that high. And then probably a LPG tweeter.

Here's where the issue comes in. the Dayton mid is only rated at around 84db sens iirc. Not to mention it will be off axis and I'm worried it may not keep up with the rest of my system volume-wise. I am coming out of a set of pioneer TS d1720c that keep up pretty well, not to mention I have my gain down pretty low until I can set it properly. But I'm thinking any less output and they wont keep up with the rest of my system. I run 2 Dayton HO 10s on a kicker zx750 for lows up to about 50hz. Does anyone know of a 8 ohm driver preferably 5.25 or 6.5 but can do 4 that plays down to 300hz, will work with the Dayton passive, and will maintain volume?

amp is Boston gt40 so 50 @ 4ohms, 100 @2ohms pretty sure its underrated though

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[CrimsonCountry]

I realize this thread is fairly old but did you ever find an answer to this? I ask because I am considering using the RS100 as well in a DIY 3-way setup and have also been looking at those passives on Parts Express.

 

[Why So Cereal? 5,000+ posts]

I realize this thread is fairly old but did you ever find an answer to this? I ask because I am considering using the RS100 as well in a DIY 3-way setup and have also been looking at those passives on Parts Express.

I ended up just going active. I figured that the passive thing was pretty much hit or miss. Since it wasn't designed around the intended drivers not even having attenuation for the drivers as necessary.

I can say though, that the lower sens of the Dayton mid would not bother me as much now knowing that your ears are very sensitive to the midrange frequencies and you should have no problems picking up on them. But, going active and being able to attenuate the drivers as needed most certainly helps in getting a good blend, and creating a natural sounding stage.

 

[CrimsonCountry]

I understand, IMO, active is much easier than passive...much easier to tune anyway. The reason I was asking that I am looking at doing a Quasi-active 3way setup (Midrange and Tweet on passive, Channels 1 + 2/Midbass on Channels 3 + 4). Because I only have a 4 channel amp (P900.4) and 6 channels of tuning (3sixty.2), a combination of active and passive is the only way to have T/A on 3-way plus sub. I found a good deal on the Alpine SPX Pro Xovers (tons of configurability, kinda T/A, and tweeter attenuation for a passive) so I may jump on them.

If that doesn't work out, I can always fall back on the Massive CK6V. If it does, I may just end up selling them as they are still BNIB.

You may be familiar with my sub choice, Dayton H.O. 10 or 12 (actually have both as found a great deal on each.) I say that because I recall seeing a for sale thread of yours with 2 10s. Also found a great deal on the Kenwood XR-1S, which should be perfect power for both (600+@4 and 700+@2ohms). I'm pretty excited, I hope they live up to my expactations/hype.

 

[Why So Cereal? 5,000+ posts]

I understand, IMO, active is much easier than passive...much easier to tune anyway. The reason I was asking that I am looking at doing a Quasi-active 3way setup (Midrange and Tweet on passive, Channels 1 + 2/Midbass on Channels 3 + 4). Because I only have a 4 channel amp (P900.4) and 6 channels of tuning (3sixty.2), a combination of active and passive is the only way to have T/A on 3-way plus sub. I found a good deal on the Alpine SPX Pro Xovers (tons of configurability, kinda T/A, and tweeter attenuation for a passive) so I may jump on them.
If that doesn't work out, I can always fall back on the Massive CK6V. If it does, I may just end up selling them as they are still BNIB.

You may be familiar with my sub choice, Dayton H.O. 10 or 12 (actually have both as found a great deal on each.) I say that because I recall seeing a for sale thread of yours with 2 10s. Also found a great deal on the Kenwood XR-1S, which should be perfect power for both (600+@4 and 700+@2ohms). I'm pretty excited, I hope they live up to my expactations/hype.

When I did the quasi active thing, I tried a few different ways to do it and what seemed to work best was with the midbass drivers on a 2 channel, and a small 4 channel (using RCA splitters) on the midrange and tweet. I didn't use a low pass on the midrange as the amp didn't allow it and I used a cap to high pass the tweet at like 8khz 6db slope. I couldnt try different xover points but I did have the ability to attenuate as needed and even with the primitive T/A I had at the time, I was able to get a solid center image and a very good sound. It took a lot of tweaking but that's still one of my fav front stage setups to this day.

After that, I went to a fully active 2 way front that also sounded amazing.

Both sets were coupled with the Dayton HO 10s and I'd recommend them to anyone. I highly doubt they'll disappoint if SQ is your goal.

 

[CrimsonCountry]

You know, thats a good idea. Not sure why but I haven't really looked into that option. I could go ahead and get the P600.2 (190x2, fully active xovers). That way I could just use Y-splitters out from 3sixty.2 on either Front or Rear output., then I will have fully active xovers on all 3 channels up front while still maintaining the T/A of the 3sixty.2. Only downfall is having to run power for 3 seperate amps (P900.4, P600.2 and XR-1S)...oh well.

I doubt the H.O.s will disappoint either. I know everyone loves them sealed (including you ha) but I may just end up running them sealed until I can design a nice, small ported box for them.

 

[keep_hope_alive Premium Member]

the type-x crossovers are flexible, but you need to be careful with the woofer and tweeter selection on them. For a 3-way application, with passive on mid/tweet the SPX-107R crossovers would be a good buy.

as mentioned, it's easier/simpler/better IMO to just have enough amplifier channels. Then you can use active crossovers (combination of processor/amp/external) to avoid impedance and phase issues with passive (as well as the inefficiencies of passives). Overall power consumption is less with an active setup compared to passive (all else equal).

T/A is more important on mids and midbass. Keep in mind that ITD is below 3kHz and IID is above 3kHz. With tweeters, level determines localization, not time arrival.

whether to combine mid and tweeter or midbass and tweeter on the processor outputs depends on a few factors. sometimes, the tweeter and midbass are near equal in distance and the mid is further away. also, some processors have separate EQ's for high and mid. with midbass and tweeter on the same output, you don't have EQ overlap like you do when combining mid and tweeter.

when i ran the H701, it had the same EQ for front 1 and front 2. i ran the tweeter on front 1 and midbass on front 2. the mids were on rear. that way i had a dedicated EQ for the midrange. this was handy so i could eq the mid (based on location/aiming/response) independent of the tweeters.

 

[CrimsonCountry]

Despite doing my research and spending way too much time looking at this stuff, I am still a NOOB. This will be my first Active/3-way setup. I am here to learn. Now, with that said....

the type-x crossovers are flexible, but you need to be careful with the woofer and tweeter selection on them. For a 3-way application, with passive on mid/tweet the SPX-107R crossovers would be a good buy.

Interesting, in what would the SPX-12/17Ref crossovers be better? After a little more research, I found a user who claimed that the SPX Pro passives are setup as follows:

"The LPF for the woofer is set between 1.4 and 1.8Khz (depending on settings) with a first-order 6db slope. The Tweeter (I think) is set at ~4.5Khz with (depending on settings) a 12db or 18db slope (third or fourth order respectively)."

Specs are nothing without the equipment, so I will add my intented setup. I chose to run the following due to finding extremely good prices on them and decent reviews:

1) RS180-4 7" Midbass / 150x2 (if the Dayton 7" doesn't cut it, I may just use my CK6V woofer as midbass as heard it has excellent midbass)

2) RS100-4 4" Midrange / ~100x2 ( since 150x2 share with tweet)

3) Vifa XT25 / ~50x2 (since 150x2 share with midbass)

I have "ballparked" the following frequency ranges for the above setup. Note, I realize these are all general and don't really mean much from one install to the next. However, I wanted some rough numbers just to get a good starting point.

1) 100hz - 400

2) 400hz (Midbass HP set on 3sixty.2)- 4khz (Of course LP for Midbass will be determined by passive)

3) 4khz+ (Tweet HP by passive as well)

I have also read that the Daytons sound great in their intended range but start to roll off quickly outside of that range. However, I haven't been able to find that "ideal" range yet....more research and experimentation on my part once I get them installed. Any general/broad ideas on if these frequencies look correct given the speakers and xover?

T/A is more important on mids and midbass. Keep in mind that ITD is below 3kHz and IID is above 3kHz. With tweeters, level determines localization, not time arrival.

whether to combine mid and tweeter or midbass and tweeter on the processor outputs depends on a few factors. sometimes, the tweeter and midbass are near equal in distance and the mid is further away. also, some processors have separate EQ's for high and mid. with midbass and tweeter on the same output, you don't have EQ overlap like you do when combining mid and tweeter.

Correct me If i'm wrong but I didn't think there was anyway that I could run the midbass and tweeter on the same channel, at least not with my current intended passives. On the 360.2, each channel can only be setup as HP, LP, FP, or BP. By using my example of tweet/midbass on same channel via passive, this would be achieved by setting a HP of 400hz (in my example) on the 360.2, the effective midbass LP would be set by the SPX crossiver as well as the tweets HP. In my thinking, one would need to have the frequencies overlap in order for the passives to divide it up b/w the speakers (ie. only midbass + midrange OR midrange + midbass). Otherwise, one wouldn't be able to properly setup the appropriate ranges.

EDIT: I can't see the picture/graph you provided on my work server. I'll have to check it at home.

 

[keep_hope_alive Premium Member]

it appears that the SPX-17PRO manual has much less information regarding slopes with each setting compared to the previous SPX-177R manual.

http://narbi.free.fr/manuels/HP%20-%20SUB/Alpine/SPX-107R_137R_177R_17MB.pdf

as you can see in this manual, all slopes (with each setting configuration) are printed. This is how all manuals should be, IMO.

i recommend buying the "better" crossovers, the previous version.