ct4870 .vs SB0100

oatie · Nov 26, 2009, 06:47 PM

Picked up a SB0100 today and reinstalled kX. After checking everything over,
I played a couple MP3's. Hmmm...ok, I thought it didn't sound as good as my ct4780. OK, the main reason I wanted to try this SB0100 was I was expecting at least a -90dbFS noise floor through the mic input. In my DAW i was only getting -69.5dbFS. So I reinstalled the ct4870 and checked the levels there again...-80.5dbFS. Cool.
2 notes here - the card is marked SB0100 on the physical card, but is called SB0102 in kX. Why? And I'm wondering if anyone else has had better results with this card than i did, maybe I set somthing wrong/missed somthing.
I was expecting better performance, and was suprised to find it seemed worse for my experiance using the SB0100. I was looking forward to a better sound and an extra 10dbFS of 'headroom', any suggestions would be very much appreciated. Thanks!

Doug W · Nov 26, 2009, 07:26 PM

Quote:

SB0100 on the physical card, but is called SB0102 in kX

I don't know about the SB0100 noise floor but the slight difference in name is common. kX renames these cards (I suppose from the exact model number in a ROM chip on the card?!?).

CT4830 might be called a CT4832.

Max M. · Nov 26, 2009, 10:40 PM

Quote:

the card is marked SB0100 on the physical card, but is called SB0102 in kX. Why?

kX Project -- FAQ (Frequently asked questions)

Quote:

I was expecting at least a -90dbFS noise floor through the mic input.

There's no reason for this. I would not expect anything at all of the cheapest mic-amp built into the cheapest audio chip (i.e. the AC97). Actually, i guess you're just lucky with your ct4870, i suspect most people get worse results with their Lives (i don't remember exact values - but you can search for similiar threads around here at the times these cards were a mainstream).
Either way, don't expect newer Live! or Audigy cards to have their mic input (the one on the back) to be better - they all use the same ac97 stuff for it (so nothing really could get better), and honestly speaking, the only purpose of that input always were/are those domestic applications like telephony and dictation. (In fact newer cards may have even more poor AC97 chips as they had to shrink newer codecs (6 channel codecs against stereo codecs of the older models) to even lower price)).

Quote:

I was looking forward to a better sound and an extra 10dbFS of 'headroom', any suggestions would be very much appreciated.

Personally, I would recommend to consider getting a card with the real mic input or a separate mic preamp.

oatie · Nov 27, 2009, 01:40 AM

Yeah, I got the mic preamp all hooked up...its one of those tube preamps and sounds pretty sweet (ART tube MP). As far as codecs go well, at this point i'd agree some of the earlier makes had better AC97 (Cirrus Logic). I think that is the difference because its exactly the same 10k1 chip on both cards. (ct4780/SB0100). I was looking at a Audigy 2 NX, but its not kX supported and I am nervous about the whole USB idea. Same deal with the MU fastrack USB, and I bet it isn't worth the coin.
***Im trying to figure out if I should use a crossover or eq on the rear channel in the DSP. Im running some old bookshelfs up there and they are nice and flat...maybe too flat (or even to treble) when paired with the Logitech THX set. I've got this crazy setup right now.... the THX set runs off the front and rear channels (4.1). The bookshelfs run off the front(swapped) as well, maybe a bit thin, as a high channel. The digital out is running to a cambridge soundworks deal for the binaural center and the second sub. I just cant get how DSP and Physical crossovers relate! So Im trying to balance the THX fL and fR with the Bookshelfs (old Allegro 1000's) both on the same channel with i guess the crossovers being...80 (THX) and 2100 (Allegro) recomended for each. Funny thing is that the Allegro's seem to sound better with a much lower split frequency than 2100, and Im just not sure how to addess the bass through the DSP for them. Any ideas? crossover .vs eq? I even tried the Phat EQ plugin, but dunno. Sometimes I get the feeling all the crossover plugins do is add or remove bass signal from the channel, basicaly the same as eq. Can the crossover in the DSP actually direct freqencies seperately to the sub/sattelites tweeter/woofers? I thought that was all done internally in the speakers physically, hence my confusion! (Im not using the LFE). So if *all the bass and *all the treble are being sent to the front and rear, how does crossover work in there?

WxMan1 · Dec 14, 2009, 10:41 AM

The crossovers are nothing more than stereo freq splitters; you put in one stereo signal and get two stereo signals out (split high and low according to cutoff and Q). The feq splitter plugin is a n order cutoff (Q is configurable)

what you do with the crossover outputs is up to you.

I'm unclear now you've got your speakers plugged into the audio card though. There is al crossover inherent to the the external amplifier for your 4.1 (or 5.1 whatever it is). Anything that's below the threshold goes to the sub-woofer, and anything above that to the satellite speakers. There may be crossover within the satellites also. In any case the DSP crossover has no bearing on operation of the external speakers.

All you can do is filter the signal and route the signals to the appropriate outputs.

Here's a link on various electronic filters:

ChannelStrip: All about EQ

I can't even begin to suggest what filtering scheme to use because I don't understand your speaker topology.

Nov 26, 2009, 06:47 PM	#1
oatie DriverHeaven Newbie Join Date: Nov 2009 Posts: 10 Rep Power: 0	ct4870 .vs SB0100 Picked up a SB0100 today and reinstalled kX. After checking everything over, I played a couple MP3's. Hmmm...ok, I thought it didn't sound as good as my ct4780. OK, the main reason I wanted to try this SB0100 was I was expecting at least a -90dbFS noise floor through the mic input. In my DAW i was only getting -69.5dbFS. So I reinstalled the ct4870 and checked the levels there again...-80.5dbFS. Cool. 2 notes here - the card is marked SB0100 on the physical card, but is called SB0102 in kX. Why? And I'm wondering if anyone else has had better results with this card than i did, maybe I set somthing wrong/missed somthing. I was expecting better performance, and was suprised to find it seemed worse for my experiance using the SB0100. I was looking forward to a better sound and an extra 10dbFS of 'headroom', any suggestions would be very much appreciated. Thanks!

Nov 27, 2009, 01:40 AM	Thread Starter #4
oatie DriverHeaven Newbie Join Date: Nov 2009 Posts: 10 Rep Power: 0	Re: Îòâåò: ct4870 .vs SB0100 Yeah, I got the mic preamp all hooked up...its one of those tube preamps and sounds pretty sweet (ART tube MP). As far as codecs go well, at this point i'd agree some of the earlier makes had better AC97 (Cirrus Logic). I think that is the difference because its exactly the same 10k1 chip on both cards. (ct4780/SB0100). I was looking at a Audigy 2 NX, but its not kX supported and I am nervous about the whole USB idea. Same deal with the MU fastrack USB, and I bet it isn't worth the coin. **Im trying to figure out if I should use a crossover or eq on the rear channel in the DSP. Im running some old bookshelfs up there and they are nice and flat...maybe too flat (or even to treble) when paired with the Logitech THX set. I've got this crazy setup right now.... the THX set runs off the front and rear channels (4.1). The bookshelfs run off the front(swapped) as well, maybe a bit thin, as a high channel. The digital out is running to a cambridge soundworks deal for the binaural center and the second sub. I just cant get how DSP and Physical crossovers relate! So Im trying to balance the THX fL and fR with the Bookshelfs (old Allegro 1000's) both on the same channel with i guess the crossovers being...80 (THX) and 2100 (Allegro) recomended for each. Funny thing is that the Allegro's seem to sound better with a much lower split frequency than 2100, and Im just not sure how to addess the bass through the DSP for them. Any ideas? crossover .vs eq? I even tried the Phat EQ plugin, but dunno. Sometimes I get the feeling all the crossover plugins do is add or remove bass signal from the channel, basicaly the same as eq. Can the crossover in the DSP actually direct freqencies seperately to the sub/sattelites tweeter/woofers? I thought that was all done internally in the speakers physically, hence my confusion! (Im not using the LFE). So if all the bass and *all the treble are being sent to the front and rear, how does crossover work in there?

Dec 14, 2009, 10:41 AM	#5
WxMan1 HardwareHeaven Lover Join Date: Dec 2007 Posts: 221 Rep Power: 40	Re: ct4870 .vs SB0100 The crossovers are nothing more than stereo freq splitters; you put in one stereo signal and get two stereo signals out (split high and low according to cutoff and Q). The feq splitter plugin is a n order cutoff (Q is configurable) what you do with the crossover outputs is up to you. I'm unclear now you've got your speakers plugged into the audio card though. There is al crossover inherent to the the external amplifier for your 4.1 (or 5.1 whatever it is). Anything that's below the threshold goes to the sub-woofer, and anything above that to the satellite speakers. There may be crossover within the satellites also. In any case the DSP crossover has no bearing on operation of the external speakers. All you can do is filter the signal and route the signals to the appropriate outputs. Here's a link on various electronic filters: ChannelStrip: All about EQ I can't even begin to suggest what filtering scheme to use because I don't understand your speaker topology.