100 watt tube amp... Sealed 15 or ported ?

4Mal · #1 09-22-2011, 10:40 PM

Scored a Music Man RD-100 and I have two 3015's on the shelf. Actually one of them is in a 2.6 cuft ported cab that with my GK, sounds pretty good for a non-fearful to me. Haven't been able to try that cab yet. Maybe tomorrow... Compactness is somewhat important as i lug PA much of the time too.

So sealed or ported ? How large if sealed ?

JimmyM · #2 09-22-2011, 10:43 PM

Doesn't matter in the least. Whatever sounds good to you will work. If the one cab is working for you, have fun.

Peg_legs · #3 09-23-2011, 04:53 AM

I'm not familiar with that head, but will say that some tube amps just don't mesh well with ported cabs. I would try it with the ported cab you have before deciding which route to choose.

Mr. Foxen · #4 09-23-2011, 05:09 AM

Don't think 3015s agree with sealed, ported is the way with those. Valve amps sound happy into my 3015 loaded cab. Or unhappy, since I play miserable music, but working right.

GBassNorth · #5 09-23-2011, 05:26 AM

I have a Musicman HD150 head, it's a combined guitar and bass head with a dedicated channel and tone shaping for each instrument input. These amps are SS pre and tube power, so kinda backwards from most hybrid amps. I've tried both ported and sealed Bergantino cabs with this head. I Love the sounds I can get out of the bass channel with the sealed cab. So when I'm in bass mode the head is run thru a Berg NV-610 non ported cab (tried it with my Berg HT-322 ported cab and didn't like it as much). When I'm in guitar mode the head plays thru a B52 412 open back cab and it just screams. Love this amp - full on Marshall overdrive with master turned way down and chanel vol at max or fender clean with master vol on max and chanel vol turned way down. For a real joy plug a vintage 2 band Stingray bass into it, a match made in heaven.

Peg_legs · #6 09-23-2011, 07:07 AM

Quote:

Originally Posted by GBassNorth

I've tried both ported and sealed Bergantino cabs with this head. I Love the sounds I can get out of the bass channel with the sealed cab. So when I'm in bass mode the head is run thru a Berg NV-610 non ported cab (tried it with my Berg HT-322 ported cab and didn't like it as much).

I had the same experience running an Ampeg SVT II through a Bergantino NV425 and the HT-322. Loved it with sealed, not so much with ported. The HT-322 was absolutely beautiful with solid state, for the record

There are threads about this where the smart guys (Fitzmaurice etc) chime in with why. Here's the bottom line, damping factor.
http://www.crownaudio.com/pdf/amps/damping_factor.pdf
Some tube amps have a knob that can adjust the damping factor to reduce boominess

JimmyM · #7 09-23-2011, 12:33 PM

Quote:

Originally Posted by Peg_legs

I'm not familiar with that head, but will say that some tube amps just don't mesh well with ported cabs. I would try it with the ported cab you have before deciding which route to choose.

Myth, sorry. Ther's no basis in fact for a sealed cab working better with a tube amp than a ported cab.

nysbob · #8 09-23-2011, 01:39 PM

I think you get a little more out of a single driver with a vented cab.

Some people think a sealed box is more responsive.

I had the choice and chose the ports.

stiles72 · #9 09-23-2011, 02:21 PM

Quote:

Originally Posted by JimmyM

Myth, sorry. Ther's no basis in fact for a sealed cab working better with a tube amp than a ported cab.

+1 I have the same PF15 driver in my double baffle (ported) cab as what is in the PF115HE cab (sealed) and while there are some differences, neither is "better" - just slightly different flavors. Having said that though - I do tend to prefer to use my V4BH (100 watts tube) on ported 15" cabs.

solodb · #10 09-23-2011, 02:28 PM

What I think I hear with all-tube amps and ported cabinets is less control of speaker excursion due to lower damping factors of tube amps and less air pressure against the speaker in the cabinet. All you tech guys , please correct me if I'm off-base here, but don't solid state heads have typically higher damping , and sealed cabinets less risk of damaging voice coil movement?

JGR · #11 09-23-2011, 03:15 PM

While both can certainly work, sealed is generally a safer bet; ported is more hit and miss. My Bag Ends and SWR 12 stacks are both ported and work great with tube heads, but they have speakers with lower excursion and aren't voiced for huge low end. They end up balancing out tube power very well.

JimmyM · #12 09-23-2011, 05:49 PM

Well it's definitely a case by case basis, and not everyone agrees which ported cabs don't go with which tube heads, so it's really something you have to decide for yourself. All I'll say is the B-15 has a ported cab and I don't hear anyone complaining

Peg_legs · #13 09-24-2011, 07:28 AM

JimmyM, First let me say that I enjoy your posts daily

there are many tube heads that sounds great with ported cabs, and there are some that don't. My SVT II sounded great through a Berg NV425. I traded that cab for a Berg HT 322 and the SVT II sounded boomy and uncontrolled. The HT 322 sounded great with allof the solid state heads I tried with it, just not the SVT II. Both the head and cab are traded away now, but if I could, I would be running an SVT II through a Berg NV 610 now.

I agree that it's a case by case issue, but definitely not a myth

JimmyM · #14 09-24-2011, 07:49 AM

OK Peg, I guess you could make a case for some ported cabs to not work with some tubers. The HT-322 is mentioned a lot by folks as one that doesn't. So I guess not a myth in some cases. I've usually done fine with ported cabs and tubers, though.

GBassNorth · #15 09-24-2011, 12:58 PM

And as a follow up, my Berg HT-322 sounds great with my Thunderfunk SS head, but way too boomy with my SVT-VR head. Can't speak for all ported cabs but my HT322 loves solid state and my NV610 sounds great with SS heads and even better with an SVT-VR head (but then again, what nonported cab wouldn't sound it's best with an SVT-VR

).