#91
|
|||
|
|||
The insertion loss is the same for both channels so it never occurred to me it could be the cables. Noise doesn't seem to be a problem but it would be interesting to solve the crime. i'm familiar with the 6dB loss that occurs going balanced to unbalanced which is why I mentioned it. I'm not nearly so smart that I won't take your usual excellent advice but I hope I have the basics covered. I was the JBL pro rep in the Pacific Northwest for 32 years, retired in 2010. Also Pacific Northwest AES chapter chairman three years running. Which doesn't make me smart but I'm older than you so be appropriately respectful! Hi Mom!
You're right of course. Voltage measurement would be definitive. I've been cheating by using the meters on the amp and preamp and a test disk with the necessary tones and noise designed specifically for this job. I have unity gain when going straight from the preamp to the amp. I drop 6dB patching in the crossover which I can make up using the mix pot. BTW, the disc is available from Barry Ober and it's tailored to this task. Actually I don't really think of it as a cheat, more like a shortcut. It's a fine sounding crossover no noise, no weirdness so as a practical matter it's not a big deal. In any case I enjoyed fumbling my way to a 90Hz tuning of the crossover last night. After this, 80Hz. The experiments will continue until the patient is cured or dies. Last edited by Pampero; 03-30-2018 at 08:06 PM. |
#92
|
|||
|
|||
Hey Rex, I edit most of my posts because I never get it down the way I want it the first time around. I think I see that you do too. Let's agree it's the sign of a perfectionist's mindset!
|
#93
|
|||
|
|||
My dad was a language freak and my sister an English teacher. I edit my posts until I get them to say what I want. Sometimes it's just fixing typos, sometimes I add ideas after thinking through things. Sometimes I have been drinking while posting and realize I should just delete it all....
|
#94
|
|||
|
|||
Quote:
I'm just throwing out ideas trying to help you get your system sounding as good as possible and solve your 6 dB problem. It would be weird to have two XLR cables with the same fault unless they were made wrong. Open them up and take a look. |
#95
|
|||
|
|||
I made them myself! You think I would do that to me? It wouldn't be the first time I did something I rued later!
|
#96
|
|||
|
|||
We're sure to know the same people and probably have passed each other without knowing it. Getting an education in pro audio provides a different point of view as a practical matter. I've found that setting up my playback systems at home teaches me many fine points I might never consider in certain pro applications and vice versa. The disciplines relate well to each other if you can pick through the marketing noise separating them.
I listened to the latest tune for 3 hours last night. I'm not able to quantify the audible differences yet but it still sounds very good . More listening time is needed. It's subtle but it feels like accuracy of level and timing parameters are equally or more important to the sound ( within a relatively narrow range of knee options). On the JLA frequencies are selected by turning a small un-detented knob that I don't find particularly easy to center. This introduces a small variable compared to a digital crossover with direct readouts or menu based settings such as you'd find on a BSS, Lake, dbx or other such digital processor. I'm learning that making sure wherever the center frequency is, level and phase settings must be very carefully attended to. That seems intuitive but it's took time to learn how to do it within my rig. I'm curious to her what Revel might recommend which I suspect would include changing to Levinson electronics and the now discontinued Ultima sub! (Laughs to self). Last edited by Pampero; 04-01-2018 at 02:17 PM. |
#97
|
|||
|
|||
Not sure what music you like, but I use Donald Fagen "Morph the Cat" for evaluating bass on both hi-fi and PA systems. Very well recorded bass and kick drum. Lots of low end you don't find on many CD's.
I would call JL Audio and ask them about the 6 dB issue. |
#98
|
|||
|
|||
I'm a pro sound guy. How could I not like Donald Fagen and Steely Dan? He's unavoidable!
Last edited by Pampero; 04-01-2018 at 06:25 PM. |
#99
|
|||
|
|||
Should have known you'd be a fan.
Just sayin', the "Morph the Cat" CD sounds better than most of the Steely Dan and Fagen catalog which are all fine recordings. It really is a benchmark recording for electric bass guitar. I use the riff on the opening track ("Morph") to balance subs with mains on PA systems. |
#100
|
|||
|
|||
Thanks for reminding me though. It's tight! I'm liking the 90Hz tune. No bass hangover, starts and stops beautifully. I'll continue to enjoy it for the moment and maybe drop down to 80Hz next week. I'm starting to think my system is petty forgiving within this range.
|
|
|
Audio Aficionado Sponsors | |