Rcf hdl20-a

[Tom Manchester]

Re: Rcf hdl20-a

If you look at the horizontal coverage of the 23A , it gets seriously beamy between 700Hz and 1.5kHz. Coverage drops from the listed nominal 100 degrees to 40 degrees at 1kHz. Off axis coverage in the critical vocal range looks to be potentially poor by RCF's own admission based on their measurements. Kind of surprising they'd ship a design like that...

http://www.rcf.it/en_US/c/document_library/get_file?p_l_id=251488&folderId=22494&name=DLFE-4420.pdf

One thing I couldnt seem to find are the conditions that the 23A were measured. Line arrays are tricky things to measure because the response can vary quite a bit depending on the setup, number of cabinets, distance of measurement mic, etc.

Measure a box designed for an 8 box array up close and it probably doesn't look very attractive, go back 25 feet and it looks good. Change that array from curved to flat and it changes completely again. It seems like a solid design by a reputable manufacturer. I'd give it the benefit of the doubt unless someone has heard a bad deployment.

 

[Silas Pradetto]

One thing I couldnt seem to find are the conditions that the 23A were measured. Line arrays are tricky things to measure because the response can vary quite a bit depending on the setup, number of cabinets, distance of measurement mic, etc.

Measure a box designed for an 8 box array up close and it probably doesn't look very attractive, go back 25 feet and it looks good. Change that array from curved to flat and it changes completely again. It seems like a solid design by a reputable manufacturer. I'd give it the benefit of the doubt unless someone has heard a bad deployment.

Everything you just mentioned is vertical coverage, which varies. Horizontal coverage is fixed unless we're talking mla.

Sent from my XT907 2

 

[Greg Cameron]

Re: Rcf hdl20-a

Everything you just mentioned is vertical coverage, which varies. Horizontal coverage is fixed unless we're talking mla.

Agreed. I was looking at purchasing a hardly used set of 12 boxes for a local theater here in my town at a killer price. After the acoustics consultant saw that beam width vs. frequency plot on the data sheet, that idea was killed. Makes me wonder if that's why the seller is blowing them out...

 

[Greg Cameron]

Re: Rcf hdl20-a

Interesting, thanks for the explanation. Is that a common issue throughout the NX line or just the LA module?

Well, the only line source top box in the current NX line is the L23A. So I guess the answer would be "yes" The NX monitors/utility boxes don't appear to suffer the same issue, but they're a different animal. The HDL20a doesn't suffer the same issue either. The higher end TTL31A II looks like it has some problems with top end coverage though, severe pattern narrowing past 1.5kHz. The TTL33 is better but has some weirdness in the mids with big rise in horizontal pattern width past 2k up to 6k. The TTL55-A looks the best behaved out of that bunch.

TTL31-A II

 

[Tom Manchester]

Re: Rcf hdl20-a

Everything you just mentioned is vertical coverage, which varies. Horizontal coverage is fixed unless we're talking mla.

Sent from my XT907 2

True, my examples we mostly related to the vertical axis, but annecdotally I've spent a lot of time working on line array measurements of several different manufacturers and have found them difficult to get reliable measurement results sometimes on BOTH planes depending on the mic setup, number of cabs, etc.

My main point though was that I couldn't find where RCF mentioned what the setup was for measurement.

 

[Greg Cameron]

Re: Rcf hdl20-a

Let's hope since they're a top end component and long time box builder that they have a clue as how to take proper measurements I'd imagine they have an anechoic chamber for doing single box measurements and a larger space for arrays. I mean, this isn't Carvin we're talkin' bout here...

 

[Tom Manchester]

Re: Rcf hdl20-a

Let's hope since they're a top end component and long time box builder that they have a clue as how to take proper measurements I'd imagine they have an anechoic chamber for doing single box measurements and a larger space for arrays. I mean, this isn't Carvin we're talkin' bout here...

I'm conflicted though because why would a top end company with access to such tools allow something with such a coverage deficiency go to market? If it truly does get as beamy as the polars would suggest wouldn't they have noticed when walking the coverage pattern of the prototype and try and fix it?

 

[Greg Cameron]

Re: Rcf hdl20-a

I'm conflicted though because why would a top end company with access to such tools allow something with such a coverage deficiency go to market? If it truly does get as beamy as the polars would suggest wouldn't they have noticed when walking the coverage pattern of the prototype and try and fix it?

All excellent questions. Anyone have any contacts at RCF to ask?

 

[Caleb Dueck]

Re: Rcf hdl20-a

I'm conflicted though because why would a top end company with access to such tools allow something with such a coverage deficiency go to market? If it truly does get as beamy as the polars would suggest wouldn't they have noticed when walking the coverage pattern of the prototype and try and fix it?

I don't have inside information, but if I had to bet...

1 - price point vs their higher end (TTL) line
2 - a slice of the VRX market

I haven't heard the TTL55A, but I like the TTL33A. The HDL20A seems to be basically the replacement of the NXL, and it's great - for the price.