PDA

View Full Version : 2235H sub help...



Sarabellum
05-28-2012, 01:14 AM
Hello Everyone!

I am building a diy sub box... I have a reconed 2235H in a custom box built to specs from WinISD data.
I acquired a 150w sub plate amp from Parts Express... it has a built in crossover. My question is this - From the pre outs on an old time Sansui G9000 reciever.. will this be a decent sounding sub? Will the pre outs work? I am not talking rec outs... I had a sub at one time years ago connected thru the speaker terminals... to sub... then to speakers... it sounded very faint.

Thanks for all input...

Lee in Montreal
05-28-2012, 05:28 AM
I will not answer your question as I don't understand it, but my only recommendation is to be carefull with a 2235 as a stand alone sub. It was not designed for that, at least not to today's standard. ;) Most likely you will have done you homework on Winsd to limit its excursion by finding the best compromise between power and how low you want to tune. Also, not a bad idea to use a high pass filter at around 25Hz.

hjames
05-28-2012, 05:48 AM
I will not answer your question as I don't understand it, but my only recommendation is to be carefull with a 2235 as a stand alone sub. It was not designed for that, at least not to today's standard. ;) Most likely you will have done you homework on Winsd to limit its excursion by finding the best compromise between power and how low you want to tune. Also, not a bad idea to use a high pass filter at around 25Hz.

Well, there was that JBL B-380 sub ... mine came from the factory with a 2235 woofer ...
but I used it mostly in home theater use with that HK Citation 22 in bridged mono mode ...
but we couldn't be in our somewhat small TV room with it the few times I tried to go stupid loud.

My receiver had a sub-out jack that I just fed to that amp ...
some of the plate amps will connect to the L & R speaker connectors of the receiver and extract a Low Freq Output, then
have a pass-through to send the rest of the signal to your main spakers once the sub signal has been extracted.

Some cabinet info is here - http://www.audioheritage.org/vbulletin/showthread.php?32031-Want-to-share-your-2235-cabinet-making-plans

I liked my old B-380, I would call it pretty musical, compared to other subs I tried.
But since I also had 2235s in my main speakers, I didn't usually run it with my music, only for movies and TV.

Sarabellum
05-28-2012, 07:52 AM
Hey All!

Most modern recievers are equipped with a pre out - sub rca jack on the back...
But my reciever is the old school 1979 series... it has a set of pre outs on the back...
I am hoping that the built in crossover on the sub amp will allow only the bottom parts of the sound to pass through...
As you can probably estimate... I am not an expert in this area...

Thanks again!

hjames
05-28-2012, 08:48 AM
Hey All!

Most modern recievers are equipped with a pre out - sub rca jack on the back...
But my reciever is the old school 1979 series... it has a set of pre outs on the back...
I am hoping that the built in crossover on the sub amp will allow only the bottom parts of the sound to pass through...
As you can probably estimate... I am not an expert in this area...

Thanks again!

I googled Plate Amps and found this example from parts Express (just an example, I have never used this brand amp)

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-807

This plate amp apparently works the way you describe - RCA outs from left & Right ... -OR- use dedicated LFE sub out jack if your receiver has one.

JuniorJBL
05-28-2012, 08:53 AM
I do not remember if your Sansui uses jumpers from the pre outs to the amp in on the Sansui, but if it does, then use a "Y" cable for each left and right to split the output. Otherwise just use the pre out for the sub.


Do not use a "Y" cable to sum Left and Right together. If you only have 1 input on the sub, use either left or right pre out.

Sarabellum
05-28-2012, 10:07 AM
Hey Guys!

My Sansui reciever has left and right rca pre outs on it... the plate amp has an lfe and also left and right input rca jacks..
Any and all help is very needful... I would really like to keep my Sansui reciever... but I love my music with a little more bottom than the old way with out a sub...


Thanks alot!

Mr. Widget
05-28-2012, 10:09 AM
I do not remember if your Sansui uses jumpers from the pre outs to the amp in on the Sansui, but if it does, then use a "Y" cable for each left and right to split the output. Otherwise just use the pre out for the sub.


Do not use a "Y" cable to sum Left and Right together. If you only have 1 input on the sub, use either left or right pre out.Exactly... and do not short the left and right channels together trying to make a mono signal... you need a buffer to do this.


Widget

JuniorJBL
05-28-2012, 10:09 AM
Hey Guys!

My Sansui reciever has left and right rca pre outs on it... the plate amp has an lfe and also left and right input rca jacks..
Any and all help is very needful... I would really like to keep my Sansui reciever... but I love my music with a little more bottom than the old way with out a sub...


Thanks alot!

It sounds like you can just run a pair of RCA's to your sub and all will be golden.:)

Mr. Widget
05-28-2012, 10:12 AM
Our posts crossed, so yeah, do what Junior said, take a left and right output from the pre outs and connect them to the Left and Right inputs on the plate amp. If your Sansui is currently using those outs via jumpers to a pair of amp inputs on the back of the Sansui, you need "Y" connectors, if the amp is internally connected and the pre-outs are purely auxiliary, then hook them up and you are good to go.


Widget