Double Bass acoustic image question

[dennis duvall]

I have an a Acoustic Image Contra series I combo (just got). I'm getting a Contra ex from Francios (on its way).I have a Yorkville Bloc40 combo w/10" 8 ohm Eminence speaker I removed the 40 watt amp and put 1/4" female plug in cabinet( to use as an external speaker until Contra Ex arrives). When I tried it, the external speaker seems twice as loud as the contra, is this due to the external being face mounted? or that there is only 1 speaker in the external as opposed to 2 in the contra. I dont want screw up this great little amp, but I'm playing Thurs. in a somewhat loud band & may need the extra volume. any help would be appreciated, Dennis

 

[bolo]

I could be wrong, but I think it's partly because your extension cab is not down-firing like you mentioned, but even moreso because it probably has a higher sensitivity than the 10" down-firing speaker in the Contra.

I don't see any harm in running the 8 ohm Yorkville ext. cab like you've outlined vs. your 4 ohm Contra extension cab that's en route. But hopefully someone else will chime in behind me and confirm.

 

[Mark Carlsen]

Hey Dennis.. Thanks for the pm, Not sure why the external cab is louder
Its 8 ohm and front facing, so you may be right there...I'm not to swift on understanding electronics, maybe fdeck is lurking around..he seems to know his stuff.

 

[bribass]

I have an a Acoustic Image Contra series I combo (just got). I'm getting a Contra ex from Francios (on its way).I have a Yorkville Bloc40 combo w/10" 8 ohm Eminence speaker I removed the 40 watt amp and put 1/4" female plug in cabinet( to use as an external speaker until Contra Ex arrives). When I tried it, the external speaker seems twice as loud as the contra, is this due to the external being face mounted? or that there is only 1 speaker in the external as opposed to 2 in the contra. I dont want screw up this great little amp, but I'm playing Thurs. in a somewhat loud band & may need the extra volume. any help would be appreciated, Dennis

I'm not all that familiar w/ the specs of the Contra, but it could be that the ohmage /and/or sensitivity of the speakers are different. ex; if you pair a 4 ohm speaker w/ an 8 ohm speaker the 8 will be lower in vol. the 4.
Also effeiciency and sensitivity of diff speakers are different.

PS Don't permantently deface your little Yorkville. Those are great little bullet proof combo amps .

BG

 

[dennis duvall]

Oh I hear ya Bribass, I've had that little Bloc 40 for years, darn near every sub I used to send in to my sit down gig in Tulsa, used to rave at that little gem. Found it in a pawn shop. That was one of the better days. Dennis

 

[MT Spaces]

Dennis ... This past thread might help your understanding a bit:
http://www.talkbass.com/forum/showthread.php?t=193842
I know that with the AI amps you can definitely mix in an external speaker with a different ohm rating and be OK. The perceived relative sound out of the two speakers depends a few things (speaker sensitivity, ohm rating, front vs. down-firing, etc.). DrURB has had input on this issue in a number of past threads. If you search this Amps Forum more, I know you can find more discussions. Good Luck.

 

[dennis duvall]

I just looked at schematic sheet in yorkville Bloc 40b and @ the speaker circuit in front of the speaker icon below 10" it says 4R ,would this be 4 ohm?. at Yorkville site they don't go back far enough for this amp in their discontinued info. Dennis

 

[Francois Blais]

I just looked at schematic sheet in yorkville Bloc 40b and @ the speaker circuit in front of the speaker icon below 10" it says 4R ,would this be 4 ohm?. at Yorkville site they don't go back far enough for this amp in their discontinued info. Dennis

Yes indeed, Dennis.
For what it's worth, I got in touch with Yorkville (Traynor) recently about a couple of combos, and both are using 4 ohms speakers.

Best regards,
François

P.S. I hope you get the Contra EX soon!