subs frequency responce

RSTERN

Not sure I did the test right. Set volume at 80db @100 hz and with out the correction factor on my radio shack meter almost all readings read higher the 80db. Some as high as 114db.

Is the problem the room or did I test wrong? Had meter set to C weight and slow responce.

The sub is a SVS 20-39pc+.

Thanks;

Rob Stern

Dr. Spec

Holy ****! First of all - DON'T do that again at that volume! You will eventually FRY your voice coil. It has no chance to rest at all for 410 seconds at you were belting out some really serious SPL.

114 dB at the couch at 30 Hz WITHOUT RS correction factor - OH MY GOD. That's like 118 dB actual SPL. Your entire room must have been vibrating!!!!

Anyway - I need to know how your bass management is set up. What size are your speaks set to, what is your filter point, and have you calibrated your system at all yet with the RS meter and if so, what method did you use.

It sounds as if your sub is running WAY hot compared to your mains. We'll get this straightened out in no time.

Email me the Excel spreadsheet so I can look at it better in Excel.

Doc

RSTERN

Dr. Spec,

Bass management:reciever sub output range;-20db- 0db, set to -5db
sub; gain set at 11o'clock, crossover on sub set at 90hz.

Have no adjustment on reciever, but I believe in 2 channel the cross over is at 150hz, when main speaker are set to small then it is 90hz.

Thank You,
Rob Stern

Dr. Spec

I see your problem immediately. Run the test with your mains set to small and left ON. The mains will be playing much if not all of the 100 Hz signal. The reason you go up to 100 Hz is to establish the relationship between the mains and the sub and evaluate the transition between them.

You tried to get the sub to play 100 Hz at 80 dB, which was way above the filter point in the receiver.

Also, make sure to run the test at 100 Hz to get well above the filter point and into the mains almost totally. If you can change your filter point to 80 Hz, do it.


Ed

RSTERN

Dr. Spec,

Set mains to small and set sub output on rec. to -10.
Turned sub gain down to between 9 and 10 o'clock and disabled the crossover on the sub, because when the mains are set to small the rec. sets the crossover at 90hz.

Here is the new chart. It is alot smoother. But why do I still climb to 95db? The ref. volume was set at 70db.

Thanks,

Rob Stern

Dr. Spec

For everyone else's information/benefit - we are emailing privately to speed up the process - he can send me Exel files that way. We'll get him set up yet!

RSTERN

Dr. Spec.
Everything's on hold right now until a new cd player. I think I found my problem. Setting in front of the player and skipping through the track I noticed the they would jump in volume all at once and if I skipped back to play it again it was not that loud at all. Even the wife picked up on this. This cd player is 8-10 years old. Not really designed to play cd-r, I guess I am lucky it does. I did start at the 100hz tone and go backward to 10hz by using the skip track button and It sounded alot better by ear, I would almost call it flat and then tapered off.

Thank again,

Rob Stern