See Bassmans post:
"There is always the McIntosh MC3500. However, IF you can find one, it will run you 20 to 30 BIG ones"
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All-Tube Power Amp? (sans pre-amp)
- Thread starter hotsnake
- Start date
See Bassmans post:
"There is always the McIntosh MC3500. However, IF you can find one, it will run you 20 to 30 BIG ones"
Thanks for explanation. I hope it helps others here
I asked a rhetorical question to a post about people "scratching their heads" wondering why some people go on about the effects on tone the power amp stage of an amp imparts.
I know why they sound different. I read books and talk to techs and look at schematics....something that requires a little more effort than typing the latest thought that comes into ones head ( the previous rant is not directed at Bassman12350).
Like I said, not much of a market.
McIntosh has been building SS amps since 1964, guess they know their market.
Mr. Foxen
Commercial User
This bit isn't really true, they are functionally equivalent in most amps, but the KT88 can be run at higher plate voltages, and has different distortion characteristics. Although I wouldn't be surprised if there are modern valves that are 6550 innards labeled KT88, the difference will be apparent on the data sheets.
http://en.wikipedia.org/wiki/6550
http://en.wikipedia.org/wiki/KT88
I guess...if your definition of a market is the greatest number of buyers willing to pay the least amount of money for something.
By your definition, I guess there isn't a market for Picasso's paintings since there are few of them, selling for millions of dollars to very few people.
Economics, like tube amps can be complicated....
I agree here, why would two identical tubes have different names ? I dont think this would happen.They may be very similar but not exact......imo.
Not to disagree with anyone, but I used to be a repair tech working at a warranty station for Ampeg and several other companies. The KT88 and 6550 tubes are identical, though the 6550 is a industrial equivalent of the KT88 and was (at least back then) designed for "rougher" use. 6550s were standard in the SVT for their ability to withstand rough service and vibration. The KT88 was designed for and used more in hi-fi applications (e.g., McIntosh). Biased with the same control gridvoltages and with the same exact plate supply voltages and signal levels, the KT88 and 6550 will be virtually indistinguishable one from the other. The only difference, should any be heard, will be the slightly lower gain the 6550 may have compared with the KT88. BTW, I take some things I read on Wikipedia with a grain of salt - - it is not always the best site for factual information.
Side note: KT88s used in an SVT will not last long (due to vibration), will sound more distorted, and are twice as likely to short out with the 795 Volt DC plate voltage on an SVT that the 6550s easily endure.
Trying to compare Picasso art to power amps of any kind
Every 6 months, someone posts thinking they want an all tube power amp for bass, MI, or PA use. They are just not being made. Very few were ever made. There is just no market.
Probably not, really. Like I've said before on this thread, they're basically the same size as regular tube heads, so there's not that much of an advantage to them. Especially since lots of tube amps can be operated as slave units, bypassing the preamp entirely.
the svt 300 power amp was not a big seller in the 90's. if any would succeed, you'd think that would have had the best chance.
Mr. Foxen
Commercial User
Check the data sheets:
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Pick out the fairly modern 6550 and KT88 there:
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Note absolute maximum plate voltages, among other things.
It is pretty much same deal as 6L6 vs EL34.
Trying to compare Picasso art to power amps of any kind
Again you miss the point. Market size can be measured a number of ways, # of participants, total value of goods exchanged or number of transactions to name a few.
If I didn't have to lift it, I would take a tube power amp of my choice over most SS amps.
The issue is that tube power amps are impractical in most mobile audio situations. The weight and cost of the transformers needed to power a tube amp, plus the % of manufacture that must be done by hand make them expensive.
Expensive to buy, expensive to operate....no wonder you see SS amps with a larger "market".
Tone on the other hand is a different matter. Think of all the songs that have been recorded using a B-15n (with a tube power section) that are the bedrock of popular music.
The cool thing is there are products on the market today that get closer to the tone every day. I played my Orange Bass terror 500 through an Ampeg 8x10 in a rehearsal studio yesterday and I was getting a great tone with a JB and pick playing RnR/Punk. The fact that you can get 75% of an SVT tone in a < 5lb package is amazing and will no doubt increase the BT "market". I think the coupling of tube pre's to class D power sections is one of the greatest things happening in the bass amp market today.
Early CD's sounded awful. As they improved the equipment, the sound got better. As technology improves, SS power amps may one day closely approximate the magical tone from a SVT or Macintosh amp.
- Dec 18, 2000
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- Disclosures
- greenboy designs: fEARful, bassic, dually, crazy88 etc
Though I generally agree with your premise, the biggest reason earlier CD releases often sounded horrible was that people in the industry were not familiarized yet with the differences and potential of the media. They weren't mastering well for it. Practices that worked well for vinyl or tape simply weren't applicable.
So it was user error more than tech.
You will notice that the link you provided calls the KT88 an exact replacement for a 6550.
Also, the 6L6 (and 6550 and KT88) is a beam forming tetrode, the EL34 is a true pentode. They are pretty different tubes, and sound it.
Completely different deal than 6L6 vs EL34.
Mr. Foxen
Commercial User
It says the KT88 can replace the 65550, but the 6550 doesn't say it can replace the KT88, that is a fairly important difference, and it fits in with the fact the KT88 is more rugged with regards to plate voltages. Which is pretty much what I was saying from the start. It is a really important difference.
As I said, functional equivalent, not identical. Much like 6L6 and EL34, you can put them in amps, and they work in the amp with some variance in sound, but they are different valves, hence the different names. They are not different labels on the same thing.
Edit: Sorry for arguing on the internet, but this sort of misinformation is what makes amps break, and broken amps make me sad.
As I said, functional equivalent, not identical. Much like 6L6 and EL34, you can put them in amps, and they work in the amp with some variance in sound, but they are different valves, hence the different names. They are not different labels on the same thing.
Edit: Sorry for arguing on the internet, but this sort of misinformation is what makes amps break, and broken amps make me sad.
On the contrary, I don't believe you are arguing at all. This is what discussion forums are about and hopefully, I am not a purveyor of misinformation myself. I am just basing my comments on my experience as an audio technician and the fact (as I remember it) that Ampeg for one, was pretty adamant about using 6550s instead of KT88s because the 6550s sounded cleaner and would hold up better than the KT88s. And I wholly agree with you - - broken amps also make me sad. Thanks for being willing to toss this information back and forth......
Funny you should say that as I was going to include that but decided it would muddy the point I was making.
I do think A/D converters have come a long way since the ones in those first machines so I think it was a tech/user learning/improvement curve.
