Legal Limit Solid State Amp - SPE 2K-FA, KPA-1500 or ??

Varistor

The EME crowd is still limited to 1500W, no?

Varistor

I don’t do FT8 and can’t speak about it. However, when it comes to CW, SSB, and RTTY I can firmly argue that it is bit the warm up time that makes people miss a DX. It’s s combination of skills and the rest of the station, particularly the antennas. I have observed quite a few ops at mega stations with lots of antennas and plenty of power; they couldn’t bust a pileup entirely because of how they operate. That is, no assertiveness and not taking the time to pause and understand how the DX works/thinks. Anyway, at the end of the day people vote with their wallets. It’s a personal choice.

W2NER

Howard

As its been stated already, it's all on your needs and viewpoint.  I'm 100% correct for my operation type, I don't do digital in any way nor do I do any amount of CW worth talking about.  So, with that said, I'm 100% correct.   The amount of OP's that require that type of duty cycle or needing that much headroom si small.  Any other reason is just bragging rights which is not worth much to me.  Also, all the hype with pure signal is a bunch of hoo haa.  If you have a reasonably clean signal (and you can take that comment way to much to the right), your good.  

W2NER

I know of a few OP's that have the KPA1500 and all state the same thing, noisy fans..  One thing I can not deal with otherwise I would have went with a Acom 2000a or stuck with my Acom 1500.

KY6LA_Howard

Since the inception of FT8 I have been virtually 100% digital albeit I have donedigtial modes since 1958. I got to 198 counties very quickly. 199 and 200 took months Headroom - especially so I can run maximum power with no distortion or splatter are critical to the other guy being able to pick me out of the noise. M. With SSB and CW they do not matter so much. But they are critical for weak signal work I run my station in the USA remote from Around the world 80% of the time so instant on is critical .. To eachhis own.

Rich - N5ZC

I just took delivery of a KPA-1500 and had concerns about noise.  My concerns are unfounded.  Yes there is fan noise but every amp has fan noise. 

I ran some tests today. 

I CQ'd at 1500 watts on 10m RTTY for 15 to 20 minutes.  I manually set the fan to setting 2 which is very acceptable even with no head phones.  The temp stayed around 60c. I would imagine that fan setting 3 may come on at some point but I don't expect it to stay on long.

Rich - N5ZC

W2NER

I love when I hear the word acceptable . Acceptable as compared to what? . What amp were you use ing before you got the 1500 ?

Bill -VA3WTB

Reading around I have read others do not find the fan noise over bearing. With these high power amps they all need to move a lot of air for cooling. Nice thing about solid state amps is the fan speed is variable. My tube amp is going full blast all the time when the amp is in use, always head phone time.

Rich - N5ZC

Acceptable to what I have heard and what I'm willing to listen to. 

I would file this one under 'subjective'.

Rich - N5ZC

W2NER

Still did not answer my question.

Rich - N5ZC

This is probably what your looking for.  Be careful making decisions based on video's as the camera's hearing location may be different than your seated position at the operating desk.  My equipment is located in a rack to the right of my operating position.  The power supply is at the bottom of the rack and the kpa-1500 is just below shoulder height.  See my qrz page for pictures.

The power supply is like a computer power supply fan.  It does not have a high pitch wine to it.

https://vimeo.com/273064144

Rich - N5ZC

W2NER

I rest my case, I have had many amps and that is a noise level I would not deal with.  If you have the correct amount of heat sinks, you don't need as much air movement.  At 60 deg C my SPE is nowhere near that level of noise.  Anyway, I'm sure the digital guys who have heavy duty cycles are the ones complaining about it. 

Rich - N5ZC

What are you resting your case on?  What fan level is don't you like. I tested the amp on rtty for 15 to 20 minutes with the fan level at 2.  No issues. I sent cq's spaced 1 second apart on 10 meters.

Like I said this is subjective by the individual.  What you don't like is just fine with others.  I used Don's video as a starting point.

If your chasing dx there's a good chance the fan won't even come on. If your contesting, manually put the fan on speed 1 or 2 (for rtty) and you'll be good to go.

I caution others making decisions based on comments like yours.

Rich - N5ZC

W2NER

i’m not a lone person complaining about the fan noise on this amp. it’s way to noisy for my liking just like one OP has already stated in this post. it’s my opinion and anyone can take it for what it’s worth. i have had many Acoms and they are the BEST in the market with cooling fan noise. my SPE at full output at 60deg C is no where near as loud as a KPA1500.

Burch - K4QXX

I've never understood why people get so bent out of shape about fan noise.  I would rather have a lot of fan noise and my gear stay cool.  I have a legal limit 2 meter amp that makes a ton of fan noise but I can hammer it all day long and it stays cool.  Fan noise is very subjective.

Rich - N5ZC

I've 'heard' just the opposite about the SPE amps and fan noise.

Rich - N5ZC

David Decoons, wo2x

I had two SPE 1.3 k amps. IMD at output level over 1000 watts is around 30 dB down. Definitely doesn’t sit in my “clean” category. Fan noise on both was louder than I would like when talking for 10 minutes on SSB rag chew. Amp power would fold back on digital modes at rates power out. I did not entertain the 1.5k when it came out. Dave wo2x

Ria

Yup, I agree with Dave - the SPE amps may have less fan noise but they trade IMD and duty cycle for that. You simply cannot run a RTTY contest at legal limit on a SPE 1.3K-FA. On a 2K-FA you might get away with it but IMD isn't as good as the Elecraft or PGXL. On a KPA1500 you can do full duty cycle RTTY. On a PGXL you can also.

Yes, Acom is a nice amp, but good luck when a DX alarm wakes you up at 5AM for a rare entity, and you wait for the 3 minute timer to countdown only to hear --.- .-. -  

Having used an ETO Alpha 91B there is no way I am going back to a ceramic tube amp... At least not one with an indirectly heated cathode.

Ria

Ria

 I can firmly argue that it is bit the warm up time that makes people miss a DX.

I have had it happen a few times. Gray line openings are short and I work long hours and sleep.  Operating skills you say? I have 325 countries including Bouvet, 9 band DXCC and 1700+ challenge. I guess I'm not skilled enough.

Bill W2PKY

I as glad to get rid of the High Voltage supplies associated with Tubes. 

Bill

Frank W2YK

Well my old Henry 3K has a TON of fan noise, but is instant on (3CX1200).  Still, looking forward to gong solid state before the year is out...

Frank, W2YK

W2NER

again it all depend on how you operate, modes and how you drive it. my 1.5k is clean if you set it up correctly. as t fan noise, again no where as noisy as the 1500. if you do digital as i already said you needs are diferant stop and look at YOUR big picture. to just say blankety that the SPE is dirty or any other solid state for that matter is being one sided and not fair to Opinions tossed out here for Recommending a particular solid-state. recommending a particular solid-state amplifier.

W2NER

also for anyone needing a real clean signal with just about any amp, go get a apache labs with a coupler for the amp and your done.......

Bill -VA3WTB

I think I would stay with poor IMD thanks..lol

Rich - N5ZC

Since none of us have all the amps being discussed we're making subjective decisions.

Do you have a kpa-1500 or have you listened to one in person?

Rich - N5ZC

Ria

I had a 1.3K and I have a PGXL. The main concern with the 1.3 is that it used a  single device rated at, at most 1.5kw. You do not want to be near the top end of the spec sheet. Even on SSB contesting it would shut down due to heat with repeated CQing with my DVK audio at 1.2kw. I had to run mine at 900 watts for it to behave.  The 1.5 may be different. 

If your operation involves round tables and nets where you are in receive mode most of the time, I can see that it would be sufficient for you. But for contesting, those who use the SPE amps don't run them hard. 

W2NER

i had the 1.3 and the 1.5 and there is a big difference in IMD and performance. i now have the 2k which IMO is a better amp with head room for my rag chew which is my normal type of QC. the 1.5k i was able to run it at 1k all day with a temp of 50 - 60 deg C with no problems. as with any solid state push it to the limit and the IMD goes up. when i had my 7000DLE i could push it close to the limit with no increase in IMD.

David Decoons, wo2x

The 7000 and apd mask the IMD of the amp. The single device amps like the SPEs and Acom 1200 have IMD that increases as you get closer to the maximum rating of the device. I run the 6600 and PG xL at legal limit with very respectable IMD (35 to 40 dB down) with no issues. That is what an amp with two devices gets you. The one side effect is with power comes heat and the need to cool it. Buying a “1.5k” amp only to have it run at 1KW in rag chew or less on RTTY isn’t what I want. So it comes down to your operating style. The SPE May be fine for most but those running higher duty cycle modes will want something better. Dave wo2x

Bill -VA3WTB

Dave I have seen you at -40 at least lately. Very good.

W2NER

dave i agree 100%. this is one reason i went to the SPE 2k and sold my 1.5k. there were other reasons of corse.