Sunn 200S/can I use at 4ohms???

[MarkG]

Had noticed from the pictures posted that the output
jacks on the 200S were 16 and 8ohms. I believe 2x15
cabinets of later vintage for the solid state Concert
Bass were 4ohms. I replaced my 4ohm Magna 2x15 years
ago with a pair of 8ohm 1x15 BullFrog cabinets,resulting
in a 4ohm setup,perfect for my Concert Bass head.I am looking
for a 200S or 2000S head,but after seeing that picture
am wondering if I can use this Bullfrog 4ohm stack
on any of these old tube heads?  

[Tom Loizeaux]

I don't know what photos you are refering to, but my two 200S heads have 2 speaker out jacks, one marked for an 8 ohm load and the other marked for a 4 ohm load.
Your 4 ohm cabinet combination will work fine!

Tom

[mike]

: Had noticed from the pictures posted that the output
: jacks on the 200S were 16 and 8ohms. I believe 2x15
: cabinets of later vintage for the solid state Concert
: Bass were 4ohms. I replaced my 4ohm Magna 2x15 years
: ago with a pair of 8ohm 1x15 BullFrog cabinets,resulting
: in a 4ohm setup,perfect for my Concert Bass head.I am looking
: for a 200S or 2000S head,but after seeing that picture
: am wondering if I can use this Bullfrog 4ohm stack
: on any of these old tube heads?  
Mark...glad you found the site...it would seem that the 200s & 2000s heads up through the end of '68 only features speaker out jacks for 8 & 16 ohm, although there is a 4 ohm tap off the out put transformer available. On my '68 2000s(which is featured in the photo gallery)you will find a 4 ohm output jack that looks like it was installed as a post-factory mod, whereas on my '71 2000s(which I erroneously listed as a '69--sorry, I wasn't paying attention)you will see only an 8 and a 4. The only reason for the difference that I could think of(someone correct me if I'm wrong)is that two 2x15 cabinets were initially suggested as the way to go(looking at the Sunn catalog at the time)--not only did it look cooler and more powerful, it would help spread the sound out(not to mention increasing sales!). To achieve this, each pair of 15's would have to be wired in series, so that each individual cabinet would be a 16 ohm load(assuming that the individual speakers were the usual 8ohms). Two 16 ohm cabs in parallel then would provide a safe load for the head of 8 ohms. If both cabs had been individually wired in parallel(which is standard now), they would would be 4 ohms, and two cabs wired that way would be a total load of two ohms, which would toast a tube amp pretty quick. The 16 ohm out would be for just one cab, of course, but I guess the company decided that no one was going for the one head/two cabs set after awhile, hence the change. After all, this stuff was all pretty expensive at the time! If anyone has any other ideas, please respond...Mark, scroll down a bit and you'll find a posting with a great picture of Noel Redding w/Hendrix live and his multiple 2000s cab set up!  

[rumblethump]

My 69 2000s has an 8 ohm main speaker out, 4 ohm ext speaker out, which I understand will switch the amp to 4 ohms.  I've been running at 2.67 ohms (a 4 ohm 2-10 and a 8 ohm 1-15) with no problems the last year and half. YMMV

: I don't know what photos you are refering to, but my two 200S heads have 2 speaker out jacks, one marked for an 8 ohm load and the other marked for a 4 ohm load.
: Your 4 ohm cabinet combination will work fine!

: Tom

[MarkG]

: My 69 2000s has an 8 ohm main speaker out, 4 ohm ext speaker out, which I understand will switch the amp to 4 ohms.  I've been running at 2.67 ohms (a 4 ohm 2-10 and a 8 ohm 1-15) with no problems the last year and half. YMMV

:
: : I don't know what photos you are refering to, but my two 200S heads have 2 speaker out jacks, one marked for an 8 ohm load and the other marked for a 4 ohm load.
: : Your 4 ohm cabinet combination will work fine!

: : Tom

Thanks all for the replies,,now I just have to find a 200S ! See Ya all..Cool board here!

[Don T.]

: Had noticed from the pictures posted that the output
: jacks on the 200S were 16 and 8ohms. I believe 2x15
: cabinets of later vintage for the solid state Concert
: Bass were 4ohms. I replaced my 4ohm Magna 2x15 years
: ago with a pair of 8ohm 1x15 BullFrog cabinets,resulting
: in a 4ohm setup,perfect for my Concert Bass head.I am looking
: for a 200S or 2000S head,but after seeing that picture
: am wondering if I can use this Bullfrog 4ohm stack
: on any of these old tube heads?  

Hello,
 Actually my sceptre which is like the 200s has jacks for 16 & 8  ohm loads too however the output transformer is tapped for all three (16/8/4). You can download the schematic and change it yourself if you have the skills.
                  Don T.

[Randy H.]

[Mike  - can you run a Hartke 3500 (350 watt) head (which has 2 - 8 ohlm speaker outs) to a sunn 215s cab (4 ohlms) and a hartke 410xl cab (hartke cab is 400 watts @ 8 ohlms) without frying anything?   (I'm Not sure what the sunn 215s cab can handle for watts).  Thanks for any assistance.

 Randy
]
On 2000-03-14 01:16, mike wrote:
: Had noticed from the pictures posted that the output
: jacks on the 200S were 16 and 8ohms. I believe 2x15
: cabinets of later vintage for the solid state Concert
: Bass were 4ohms. I replaced my 4ohm Magna 2x15 years
: ago with a pair of 8ohm 1x15 BullFrog cabinets,resulting
: in a 4ohm setup,perfect for my Concert Bass head.I am looking
: for a 200S or 2000S head,but after seeing that picture
: am wondering if I can use this Bullfrog 4ohm stack
: on any of these old tube heads?  
Mark...glad you found the site...it would seem that the 200s & 2000s heads up through the end of '68 only features speaker out jacks for 8 & 16 ohm, although there is a 4 ohm tap off the out put transformer available. On my '68 2000s(which is featured in the photo gallery)you will find a 4 ohm output jack that looks like it was installed as a post-factory mod, whereas on my '71 2000s(which I erroneously listed as a '69--sorry, I wasn't paying attention)you will see only an 8 and a 4. The only reason for the difference that I could think of(someone correct me if I'm wrong)is that two 2x15 cabinets were initially suggested as the way to go(looking at the Sunn catalog at the time)--not only did it look cooler and more powerful, it would help spread the sound out(not to mention increasing sales!). To achieve this, each pair of 15's would have to be wired in series, so that each individual cabinet would be a 16 ohm load(assuming that the individual speakers were the usual 8ohms). Two 16 ohm cabs in parallel then would provide a safe load for the head of 8 ohms. If both cabs had been individually wired in parallel(which is standard now), they would would be 4 ohms, and two cabs wired that way would be a total load of two ohms, which would toast a tube amp pretty quick. The 16 ohm out would be for just one cab, of course, but I guess the company decided that no one was going for the one head/two cabs set after awhile, hence the change. After all, this stuff was all pretty expensive at the time! If anyone has any other ideas, please respond...Mark, scroll down a bit and you'll find a posting with a great picture of Noel Redding w/Hendrix live and his multiple 2000s cab set up!  
[/quote]

[Rocketboy]

You should be ashamed of yourself for using BULLFROG products with anything other than Peavey power.

[Rocketboy]

Upon further review, Bullfrog products appear to be quite usable with a Sunn head.  Shame on me.  Ricardo Rocketboy

[Rocketboy]

Seriously, if you don't feel like getting inside the amp and messing with the OT/negative feedback loop, you can easily build a box to help you.  The box can be heavy plastic or polycarbonate (Radio Shack or equivalent).  Simply install three 1/4" phone jacks in the box and wire them in series.  Then, using standard speaker cables, your two eight-ohm cabinets will present a total load of 16 ohms to the OT.  This is a neat trick when you want to avoid a bunch of speaker cabinet rewiring, also.  Rocketboy