Photo from Axpona

[jjptkd]

I was wondering about that myself, didn't make much sense to include a "Sunfire" sub with a new company offering.

[EndersShadow]

I would love to hear a pair of CRM-2's paired with that sub

[Martin1970]

OK, some info on the CF tube amps from Bob F:

"We will provide an update on the schematics to all those who bought Carverfest amps, as well as provide the new parts at our cost plus freight to those who wish to upgrade their units.

Right now - this design is not finalized – we are waiting for Bob to test the custom wound power transformers (that will have less hum) and then I hope we can release it."

Also:
"And to specifically answer the question asked:

Changes being made will improve the reliability of the units as the power transformer rail voltages are being brought down so as to not exceed the rating on the tubes (and also wound differently so they do not hum so much).

There are some value tweaks for sonic improvement, layout mods to reduce cross talk, a mono switch (for a 40W mono amp option) and an input attenuator pot and chrome roll bar like on the big boy amps. We will also have nice silkscreened trims.

Also, it will still be point to point – but have blank circuit boards (no board traces) with swedged in turrets and parts soldered on by hand to reduce the “head in chassis” labor time for assembly. Much like the 180s and 305s actually."

[BrianT]

OK, some info on the CF tube amps from Bob F:

"We will provide an update on the schematics to all those who bought Carverfest amps, as well as provide the new parts at our cost plus freight to those who wish to upgrade their units.

Right now - this design is not finalized – we are waiting for Bob to test the custom wound power transformers (that will have less hum) and then I hope we can release it."

Also:
"And to specifically answer the question asked:

Changes being made will improve the reliability of the units as the power transformer rail voltages are being brought down so as to not exceed the rating on the tubes (and also wound differently so they do not hum so much).

There are some value tweaks for sonic improvement, layout mods to reduce cross talk, a mono switch (for a 40W mono amp option) and an input attenuator pot and chrome roll bar like on the big boy amps. We will also have nice silkscreened trims.

Also, it will still be point to point – but have blank circuit boards (no board traces) with swedged in turrets and parts soldered on by hand to reduce the “head in chassis” labor time for assembly. Much like the 180s and 305s actually."

Martin

Thanks for the update, looks like some interesting things are happening on our Baby Black Beauties

Brian

[jjptkd]

I had a Subrosa at one time, beautiful speaker and its slim, 3.5" profile make it very unique. Performance wasn't what I expected, at least in my room. It didn't seem to hit as low, no where near as hard or play as loud as the True subwoofer MK II I had at the time. Upper frequencies may have been a little better, possibly making it a better match for the Sunfire ribbons but the inability to corner load the sub really hurt its total output, again, at least in my room, others may have had better experiences with it. Also, just because its thin does not mean its small. If I remember right, its about 4' wide.

[EndersShadow]

I had a Subrosa at one time, beautiful speaker and its slim, 3.5" profile make it very unique. Performance wasn't what I expected, at least in my room. It didn't seem to hit as low, no where near as hard or play as loud as the True subwoofer MK II I had at the time. Upper frequencies may have been a little better, possibly making it a better match for the Sunfire ribbons but the inability to corner load the sub really hurt its total output, again, at least in my room, others may have had better experiences with it. Also, just because its thin does not mean its small. If I remember right, its about 4' wide.

Yeah, I saw the specs. I think its meant to be put between the CRM's but I could be wrong....

Interesting about it not performing as well as you would like. If I remember correctly it was made for the CRM's.

[jjptkd]

I think it was actually designed later for the "on-wall" CRS-3 line, all of which were designed to be mounted around a flat screen TV.

[jjptkd]

Here's a link to the brochure picturing the CRS-3 / Subrosa combo:

http://www.sunfire.com/brochures/Sunfir ... 08_web.pdf

[Martin1970]

Are you at liberty to say whether these changes are for the reliability of the unit or sound? Perhaps both?

is this amp still going to be point to point, or will it have printed boards?
lower voltage?
so many ??????????????'s

Hi All,

The changes are for reliability as well as mechanical hum from the transformer. Not hum out of the speakers, just a low level buzz hum from the transformer itself. If you can't hear it from your listening position it does not need changing.
The screen voltage is regulated with the updates, along with new EH high voltage 6BQ5 tubes. Together they increase much needed reliability. And an increase in output power as well.

I am very happy with the sound, but the new output transformers give more power below 50 Hz. Not at all necessary if you use a powered subwoofer with your system.

Bob Carver

[tinpan]

"We will provide an update on the schematics to all those who bought Carverfest amps, as well as provide the new parts at our cost plus freight to those who wish to upgrade their units.

Rabbit, I can't wait...can you?

Seriously, this is fantastic news. I really like the idea of lower plate voltage, if that is what this means, then we would have more options for tube rolling.

I really like the pair I have, but honestly would like to see some of the hotness taken out. I took mine off my Lowthers because of fears of the supernova re appearing, plus I was hearing a whistle coming out of one amp. When I took the Lowthers off and put some lower efficiency Snells on the whistle disappeared.

I think these little kit amps far exceeded what anyone was expecting, but with a little up grading I think these will make the next transition.

Very cool and very nice of Bob to offer this.

[treitz3]

I think these little kit amps far exceeded what anyone was expecting, but with a little up grading I think these will make the next transition.

I can tell you that the sound definitely surpassed my expectations. One thing we tried down at Jerry's pad was to A/B the stock CF amps, one with 12AX7's and the other with the original tubes [however, upgraded]. It was agreed by all there who observed the A/B that weekend that the 12AX7 had a clear superiority over the original type tubes. This was done on a pair of Apogee speakers, of all things. Not the easiest speaker to drive...but this amp held its own. Even against Jerry's VTL's at I believe more than 3X the power.

Very cool and very nice of Bob to offer this.

Indeed!

[TNRabbit]

"We will provide an update on the schematics to all those who bought Carverfest amps, as well as provide the new parts at our cost plus freight to those who wish to upgrade their units.

Rabbit, I can't wait...can you?

Seriously, this is fantastic news. I really like the idea of lower plate voltage, if that is what this means, then we would have more options for tube rolling.

I really like the pair I have, but honestly would like to see some of the hotness taken out. I took mine off my Lowthers because of fears of the supernova re appearing, plus I was hearing a whistle coming out of one amp. When I took the Lowthers off and put some lower efficiency Snells on the whistle disappeared.

I think these little kit amps far exceeded what anyone was expecting, but with a little up grading I think these will make the next transition.

Very cool and very nice of Bob to offer this.

Robin, I have them all packed up & ready to go to Bob as soon as he sends me an address. I can ask him to go ahead & include the new power & output transformers if you'd like~

[Chauss]

I think these little kit amps far exceeded what anyone was expecting, but with a little up grading I think these will make the next transition.

I can tell you that the sound definitely surpassed my expectations. One thing we tried down at Jerry's pad was to A/B the stock CF amps, one with 12AX7's and the other with the original tubes [however, upgraded]. It was agreed by all there who observed the A/B that weekend that the 12AX7 had a clear superiority over the original type tubes. This was done on a pair of Apogee speakers, of all things. Not the easiest speaker to drive...but this amp held its own. Even against Jerry's VTL's at I believe more than 3X the power.

Not quite the same comparison Jerry, Bob ( a friend of Jerry's) and I made- the 6AX7 lacks some in the deep bass / punch, but the detail compared to the 12AX7's is astounding. Guess it all depends on what kind of sound you like? Decided not to change mine out to the 12's- at least until I can no longer find good replacement tubes for the 6AX7's. If you like rock n roll- the 12's are probably the better choice. I helped Jerry set up / re-position the speakers too for better sound in his room. The little Black beauties sounded great driving the Apogee's- (I was shocked- because the Sunfire 300 x 2 did not sound near as good) but they did not have near the "air" the VTL's produce....not even close - but they did put up an amazing fight! These little puppies pack quite the PUNCH for such a "lightweight", Bob hit a homerun with this design!

~Cheers!~

[tinpan]

I'll send you an email, I'd be more than willing to pay him or his staff to install the upgrade and do the 12ax7 switch as well don't want to push it but if he will I'm interested


Once he gets the revised complete


Sorry to hijack your thread kingman