adjusting x-over

Is this amp OK?
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Rich4349
Posts: 855
Joined: Wed Jul 30, 2008 10:18 am
Location: Kankakee, IL

adjusting x-over

#1 Post by Rich4349 »

I picked up some Ashly FTX-2001 amps. They have a factory set crossover point of 750hz, that I want to change to 100 and have them be more ready to go out of the box. I have instructions from Ashly to swap out the resistor arrays inside, using parts from Digikey. Only one of the three possible choices is available from them, though, unless I want to buy 2000 of them. The choices are:

100 kohm = 113 hz (available singly)
110 kohm = 103 hz (out of production)
120 kohm = 94 hz (sold in units of 2,000)

The only one available in normal consumer quantities is the 100k, but I'd rather set the point closer to 100. Is 113 that bad? Does anyone know of other parts sources for resistor arrays in quantities of less than a googoolplex?


http://www.digikey.com/products/en/resi ... ageSize=25
2 DR250s, 2 27" Lab15 T-60s, 2 30" Neo Titan 39s, 1 Autotuba...and looking for more!

jimbo7
Posts: 849
Joined: Fri Dec 28, 2012 10:45 am
Location: St. Louis

Re: adjusting x-over

#2 Post by jimbo7 »

Try Mouser.

P.S. I hate buying crossover parts from P.E., but it's so convenient when you make a large order.
BFM builds:
XF212
T24 BP102 24"
2x SLA's 6-5" mids, 9- gt-302's
2x AT 14" MCM 55-2421
TrT 5" MCM 55-2421
AT 18" JBL GTO804
2x OT12 flat array
2x SLA Pro 2-Alpha 6's 2-Goldwoods
2x T39 24" 3012lf
Simplex 10 BP102

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J_Dunavin
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Location: Appleton WI
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Re: adjusting x-over

#3 Post by J_Dunavin »

http://www.newark.com/bourns/4608x-102- ... dp/32K9935

Not sure the number of elements you need.... You know, you could just make your own with fixed metal film resistors, on a small piece of proto board.
Not pretty, buy it would work and get the exact freq you want.
2 - OTop8
2 - T39
8 - DR200
2 - DR250
9 - T24
6 - T45
1 - Auto Tuba

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Mkulu
Posts: 121
Joined: Tue Aug 19, 2014 9:46 am
Location: Durban,South Africa.

Re: adjusting x-over

#4 Post by Mkulu »

Rich4349 wrote:I picked up some Ashly FTX-2001 amps. They have a factory set crossover point of 750hz, that I want to change to 100 and have them be more ready to go out of the box. I have instructions from Ashly to swap out the resistor arrays inside, using parts from Digikey. Only one of the three possible choices is available from them, though, unless I want to buy 2000 of them. The choices are:

100 kohm = 113 hz (available singly)
110 kohm = 103 hz (out of production)
120 kohm = 94 hz (sold in units of 2,000)

The only one available in normal consumer quantities is the 100k, but I'd rather set the point closer to 100. Is 113 that bad? Does anyone know of other parts sources for resistor arrays in quantities of less than a googoolplex?


http://www.digikey.com/products/en/resi ... ageSize=25
Try Parts Express, if they don't have they will tell you where you can get them in small quantities.

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dswpro
Posts: 314
Joined: Sun Oct 30, 2011 3:17 pm

Re: adjusting x-over

#5 Post by dswpro »

You could also look for a higher wattage resistor at Digi_key to see if they carry those in smaller quantities.
If you were searching for 1/4 watt, look for 1/2 watt. Also try higher precision. If you were looking at 5% try 1%.
Just a thought.

David Raehn
Posts: 676
Joined: Tue Apr 30, 2013 5:56 pm
Location: Colonial Beach VA

Re: adjusting x-over

#6 Post by David Raehn »

Try Tayda. They're overseas but their standard shipping will put it at your door in a couple of days.

Post an example of the arrays. I might have some in my own stock.
BFM rig:
6 OT12
4 T48
4 WH8
Other:
56 box Electrotec LabQ rig
Way too many cables
:noob:

billkatz
Posts: 249
Joined: Mon Jan 21, 2013 9:30 pm
Location: San Rafael, CA

Re: adjusting x-over

#7 Post by billkatz »

Rich4349 wrote:I picked up some Ashly FTX-2001 amps. They have a factory set crossover point of 750hz, that I want to change to 100 and have them be more ready to go out of the box. I have instructions from Ashly to swap out the resistor arrays inside, using parts from Digikey. Only one of the three possible choices is available from them, though, unless I want to buy 2000 of them. The choices are:

100 kohm = 113 hz (available singly)
110 kohm = 103 hz (out of production)
120 kohm = 94 hz (sold in units of 2,000)

The only one available in normal consumer quantities is the 100k, but I'd rather set the point closer to 100. Is 113 that bad? Does anyone know of other parts sources for resistor arrays in quantities of less than a googoolplex?


http://www.digikey.com/products/en/resi ... ageSize=25
You don't need that fancy isolated SIP - you could use 4 generic 1/4W axial lead resistors.
Built:
1 Omni-15 Tall Boy
2 DR250s
2 Titan 39s

CoronaOperator
Posts: 1648
Joined: Wed Mar 25, 2009 7:07 pm
Location: Medicine Hat, Alberta, Canada

Re: adjusting x-over

#8 Post by CoronaOperator »

With DSP's almost a necessity is it worth the bother to use the built in one's?
Built:
17" width 10" driver Autotuba
2 x 29" width dual Lab12 Tuba60
6 x DR250 2510/asd1001
In progress:
2 x DR250 2510/asd1001
For best results, point the loud end of the array towards the audience

David Raehn
Posts: 676
Joined: Tue Apr 30, 2013 5:56 pm
Location: Colonial Beach VA

Re: adjusting x-over

#9 Post by David Raehn »

BFM rig:
6 OT12
4 T48
4 WH8
Other:
56 box Electrotec LabQ rig
Way too many cables
:noob:

Rich4349
Posts: 855
Joined: Wed Jul 30, 2008 10:18 am
Location: Kankakee, IL

Re: adjusting x-over

#10 Post by Rich4349 »

Thanks all, found some and they're on the way.

(And to answer the "why not just use DSP? question: I may very well just use one of the amps in the house where I won't be pushing my speakers even 1/10th as hard as PA.)
2 DR250s, 2 27" Lab15 T-60s, 2 30" Neo Titan 39s, 1 Autotuba...and looking for more!

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subharmonic
Posts: 2061
Joined: Sun Mar 14, 2010 1:57 pm
Location: Mandan ND

Re: adjusting x-over

#11 Post by subharmonic »

Why not use a DSP. The FTX have a modular input board: 2 or 3 way x-over, comp/limiter, mixer, or regular 2 channel input with gain. Most out there that I have seen have a 2 channel cross, which make it a 1 channel input. This is great for guys like us to skip passive crossovers in place of a dollars worth of resistors. I also talked to Ashly as I bought 6 of these amps. They recommended to just bypass the board and go straight into the input section for 2 channel use when the crossover is installed, citing no real need for gain control if you can control the levels elsewhere. Also a 2.2 k resistor in line with the fan makes these bad boys whisper quiet for home use.

Why resurrect this post? Because I regularly see these floating around ebay $120-175 each and they sound incredible IMO, I put them against a Marantz 8001, Crown XTI, Behringer A500, Behringer 1500, Sonitec 650, and Ashly KLR2000. The difference is there. Not saying it is the Mosfet or whayever but the sound was noticeably superior. They basically sounds less harsh, more detailed and full, almost liquidy for lack of a better term.

We are using 2 of them in our church to run DR250s and T39s. With the built in xover you can run 1 channel full range, 1hi/1low or both low. Works great for sub duty.

The FET and CFT series amps are in the same class I also have a FET 1500 running my mains in my media room.

Lastly be careful about the sellers, most seem to have gotten these as lots from old cinemas so at least they were installed and ran properly, if not ran a lot. However the ones I ordered for the church were mismatched (1 regular input and the other 750hz xover) and the seller would not send the regular input card, but as we run active. I have tried to buy/swap cards from sellers of lots and most have no clue until I ask, then those always seem to be sold first. Also make sure to ask how they are packaging, i have had issues with pro gear being sent with air bladders that get popped during shipping and stuff slides around then, so far only 1 item had to go in for repair but I nail sellers for carelessness.

Hope this helps someone that may be looking to up their residential system game on the cheap. BTW paired 2 of these on some TLAH through a Spatial Coherence TVA1 for some serious 2 channel listening, 3D sound is amazing in the right recordings.
2x T39, 1x T60, 1x THTLP, 1x AT(not built by me) 6x DR250
I need more bass

But this gal's built like a burlap bag full of bobcats
CW Mcall

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