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cookiesowns

join:2010-08-31
Irvine, CA

1 edit

Model suggestion for Ultimate

Hey guys,

Currently shopping for a new D3 modem. We have a SB6120 on latest firmware currently and it works great. Bonding 4/1 right now in OC 92606. On premier planning to upgrade to ultimate in the next few days. I've read abit about SB6180 vs SB6141, and it seems that SB6180 has 32mhz spacing instead of 96mhz spacing on the SB6141 or something like that. Which one would be better for me? I don't need the best throughput, but rather lower latency AS MUCH as possible ( jitter as well )

Here are my signal levels uptime is 2 days:

Downstream Bonding Channel Value
Channel ID 1 2 3 4
Frequency 573000000 Hz 579000000 Hz 585000000 Hz 591000000 Hz
Signal to Noise Ratio 37 dB 37 dB 37 dB 37 dB
Downstream Modulation QAM256 QAM256 QAM256 QAM256
Power Level
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
-1 dBmV 0 dBmV -1 dBmV -1 dBmV
Upstream Bonding Channel Value
Channel ID 1
Frequency 23810000 Hz
Ranging Service ID 251
Symbol Rate 5.120 Msym/sec
Power Level 41 dBmV
Upstream Modulation [3] QPSK
[3] 64QAM

Ranging Status Success
Signal Stats (Codewords) Bonding Channel Value
Channel ID 1 2 3 4
Total Unerrored Codewords 8231120976 8231121121 8231121198 8231120951
Total Correctable Codewords 644 319 258 559
Total Uncorrectable Codewords 4959 5071 5110 5080


Optimus2357
Premium
join:2010-11-21
West Warwick, RI
kudos:3

Re: Need new model suggestion ultimate

I would say SB6180. From what I understand, using dual capture windows is a cheaper way of bonding up to 8 channels without the two independent tuners that the SB6180 has. I could be wrong, and I wonder if something needs to be compatible at the Head end level to even make use of the cheaper method(Comment from a Blue?), but I do know for sure the SB6180 is capable of 8x4, since I have one and its running that way as we speak.

SB6141
»www.motorola.com/staticfiles/Vid···S-EN.pdf

vs

SB6180
»www.motorola.com/staticfiles/Vid···heet.pdf


skeechan
Ai Otsukaholic
Premium
join:2012-01-26
AA169|170
kudos:2
reply to cookiesowns
I have an SB6180 and have no problem on Ultimate in OC but in my area (Nellie Gail) we're only doing 4X1 right now.

EyeInTheSky

join:2010-09-20
Las Vegas, NV
reply to cookiesowns
I just replaced my DPC3000 with a SB6141 here in Las Vegas, NV using Cox Ultimate.

Showing 8 bonded channels down, and 2 bonded up.


skeechan
Ai Otsukaholic
Premium
join:2012-01-26
AA169|170
kudos:2
reply to Optimus2357
So these modems are the same, capability-wise, just the 6141 uses a Ti chipset and the 6180 uses Broadcom?

EyeInTheSky

join:2010-09-20
Las Vegas, NV
I believe so, based on what I have read elsewhere.

Next models will be 24x8!
»www.prnewswire.com/news-releases···842.html


Optimus2357
Premium
join:2010-11-21
West Warwick, RI
kudos:3
reply to skeechan
There's probably a bunch of tiny differences between the two, but the main one is the SB6180 has two physical tuners inside while the SB6141 only has 1. This may have some pro's and con's. I would think with two tuners, issues on freq that the first tuner is using is less likely to effect the other tuner. But I would imagine they would have to split the signal internally to give the signal to the two tuners. Assuming that is true, the SB6180 may not handle lower signal levels as the SB6141 in real life scenario's.

Only way to be sure is buy both and compare. But in my book, signal levels can always be improved, so go with the hardware with more capabilities; SB6180.


Optimus2357
Premium
join:2010-11-21
West Warwick, RI
kudos:3
reply to EyeInTheSky
said by EyeInTheSky:

I believe so, based on what I have read elsewhere.

Next models will be 24x8!
»www.prnewswire.com/news-releases···842.html

Yea, I saw Intel has a similar chip. I think will be a while though before any ISP starts using 24/8. Not until the pricing on 100Mb+ becomes low enough to become the norm. Maybe 1-2, but probably closer to 3-4.

EyeInTheSky

join:2010-09-20
Las Vegas, NV
reply to Optimus2357
Top post on this page talks about tuners:
»Re: sb6141, sb6180, zoom5341, dpc3010


Optimus2357
Premium
join:2010-11-21
West Warwick, RI
kudos:3
Very informative, thank you. However, the source he was quoting from, Broadcom, could very well be a bias source. I mean, of-course they are going to say their newer chip is better. Any engineers (even if non-cox) have a opinion of which performs better in Cox's general infrastructure?


DrDrew
That others may surf
Premium
join:2009-01-28
SoCal
kudos:17
said by Optimus2357:

...which performs better in Cox's general infrastructure?

Cox, like any large cable provider, has an infrastructure that varies depending on the area. Different CMTS makes, models, software, and configurations. Yes, they try to get it homogenous over the years, but it never really is.

Then you have to deal with the different modem models AND firmware versions.

This all means a modem which works perfect in one area may have odd issues in another.
--
If it's important, back it up... twice. Even 99.999% availability isn't enough sometimes.


Optimus2357
Premium
join:2010-11-21
West Warwick, RI
kudos:3
Yes, but both methods must work across the network if its on the Cox approved modem list. So I was looking more for a Engineers opinion on what method generally works better in their opinion. Yes, it may be bias to their particular area, but at-least it would be real life input vs what we can read on a datasheet.

cookiesowns

join:2010-08-31
Irvine, CA
reply to cookiesowns
Understood guys.

I'll try and look for a SB6180. That said, how are my signal levels looking?

Just noticed the fail typo on the Thread title, made the thread at around 4AM =/

Would upgrading to a higher tier possibly improve latency and jitter as well?


Optimus2357
Premium
join:2010-11-21
West Warwick, RI
kudos:3
Signal levels look decent. Your SNR is a little low given your Downstream power levels. Not that 37 is bad, but if your getting -1 with no amp (Im assuming) I would expect it to be 39-40. Do you notice any problems?

And no,as a rule, changing tiers won't effect latency or jitter.

m8trix

join:2003-12-24
Phoenix, AZ
kudos:4
Reviews:
·Cox HSI
the snr is not always a direct reflection of what is down stream power level is so the snr is not low. cookie as long as your snr is 35db or higher you are ok

levels should be as followed

downstream between +10 to -10 close to 0 a possible
SNR 35db or better
upstream 40-50 db


Optimus2357
Premium
join:2010-11-21
West Warwick, RI
kudos:3
Apologies, I didn't mean to insinuate any signal level was bad. I was just speaking as compared to mine which I guess aren't normal? I will leave it up to the pro's next time. 10-4


LordFlux

join:2005-04-20
reply to cookiesowns

Re: Model suggestion for Ultimate

I'm using a SB6120 with 4/1 bonding on Ultimate tier. It works well and I get the advertised speeds, but I've often wondered if I could squeeze out a little more performance with a newer model D3 modem.

If you don't mind, post up your impressions once you get everything setup. Would like to hear.

cookiesowns

join:2010-08-31
Irvine, CA
Alright guys, just got the upgrade today. Still using the SB6120 that's currently provisioned.

Speeds are hitting 65/6 with boost, and about 50/4 sustained which I would say is good enough.

Now for those that say latency does not improve or change with the upgrade, I would say this is false. I'm getting on average worst case 2MS BETTER than before, with improvements up to 8MS better! =)
»speedtest.net/result/2553479483.png