ReelTrouble, Amps for your SouldLabs!

megasat16

ReelTrouble (RT1)

Here is the amps for your soundlabs. It's only 25W into 8 but 400W into 0.5ohms load. I hope your SL dips really low with this.

Apogee owners undoubtedly love these old man's sand amp. I would buy these if I don't have a ton of sand amps already.

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1250852044&/Mark-Levinson-ML-2--Mono-Block


James

Systems

Yep them's classics.

dorokusai

Shipping from Hawaii....I don't think so.

reeltrouble1

figures they are from Hawaii with all that sand.

Love it Mega, I mean the Mega, reminds of those robot guys, except you should be MegaSand instead of Stat.

Well you can ship them to me for a trial, I suspect trouble, but if they dont work out they'll make a hell of boat anchor. They actually are some serious amps, H9 would dig em, did you catch the ad "they have high currency" a bit of a Freudian slip there??? Anyway, yea that are man amps.

FYI the SL dip to low ohms in the treble.

RT1

megasat16

Old man, wear your glass when reading in the forum. My handle is Megasat but for some reasons, you and others think it's Megastat. I think Megasand would be cooler ID but too late to change now? Anyway, my signature reveals my affection to sand.

I did not catch the part of the ad you pointed out but the cost is High enough for Currency.

As long as your soundlabs dips low (really low), the ML2 would have enough juice to power them.

As for the Demo, I don't have them or otherwise I'll send you a pair so you can enjoy Oasis in the sand.

Edit : Shipping from Hawaii can be a hassle but if the seller has Original Box and choose 2nd day shipping, I think it's relatively safe compared to regular ground shipping in the 48 states.

reeltrouble1

You see that would be the thing, the impedance curve is all over the place, so since the bass impedance might rise to 100K this can cause problems, although one would say, well, its an easy load to drive, the amount of current any amp can supply at this impedance is limited and then along comes a big bass transient and the amp falls on its butt then you hit an immediate treble transient at 1 ohm or so and the amp says WTF!!! and gives it up with a puff and a flash, scompracer experienced this with his panels as an example, of course things like damping, slew rate and such contribute, then the SL are a reactive load and so on. So whether tube or sand, its a tough speaker to drive, but oh my the sounds it put out, last guy in the Loft stated he had never heard a rig with better vocals. When an instrument takes center stage for their solo the texture of sound makes for a big time woody.

I nearly bought a bigger pair of SL last week, but decided to hold to this pair for now, only had them six months or so and its just not enough time, hell they are just getting fully broken in as the panels were factory replaced as well as all the electronics to bring them up to what SL calls their px level.

RT1

megasat16

SL is very interesting speaker and I should try to get opportunity to listen to it in my rig sometimes. I hope my sand amps are up to the task.

When you are talking about the speaker load impedance all over the place (dips very low and climb very high), it's the more you need to have an amp with higher resolution. I think it's the more reason you need to try the sand amps. Why not give a try on PASS. High Power, High Resolution with Wide Bandwidth should help a bit.

reeltrouble1

because the Wolcott's are great and with their adjustable damping they are a noted amp for SL, some say The Amp for SL others like atma-sphere otl, VTL big blocks, the Antique Sound Lab Hurricanes do well, for ss Parasound JC1 for a low cost option and many like the Ayre monoblocks. like any audio nut though there will come a time for me to change, I did the sand/tube pre thing for quite a while and it is very satisfying I used a large BAT with my Carver Amazings, the BAT was a great amp.

RT1

megasat16

If JC1 can handle SL panels, I think there are many others sand amps which can handle it. But how it sound is more of a concern and Tubes may be more appealing as said in one of the reviews I've read before.

In fact, I did a few readings on SL site and I found this but I think it applies to their newer panel designs.

http://www.soundlab-speakers.com/faq.htm#12

reeltrouble1

hehehehe, yea I read that before I bought them, what do you expect......Our speakers are very difficult to drive and you may have to get a different amplifier to really enjoy them?????

They have changed the stator design with the latest px sets which is said to help a bit with driving the speakers, however, in my conversations with actual owners they are still a speaker from hell. Sure high current amps can drive them but I put a 200 watt 85 ampre pk2pk on mine and they sounded like **** and I could not get over 85db SPL before the amp would crap out and blow a fuse. I know my dealer uses those high end belles mono-blocks the big ones and the big boy Levinson, he is a dealer for both. Pass is a possibility, but first I think maybe that new VTL big block I think they are like 440watts or something such, too expensive right now for me, besides gotta get a bigger air conditioner for the Loft.

The dealer he let me listen to some 100 grand Beverridge while he was packing up my SL, they sounded nice.

RT1

megasat16

hahaha...so, these FAQs almost got me. But look at this way -

1. $5K speakers requires 20K electronics to drive them for a good sound. or

2. Spend $20K for speakers and $10K in electronics.

I think No.1 seems a bargain to me.

reeltrouble1

yes, I have noticed a trend where hi-end electronics are being used with so-called mid grade speakers with rather grand results, a good example was the party at Matt Polk's some here went to, he had a hi-end Marantz SACD source, ARC tube pre (Doro's) and 1000 watt Threshold mono-blocks, hooked to a set of stock Lsi-9. Never heard the 9's sound so good, vocals hung just rights and these little speakers did fill the room with music, only thing negative I could say was the bass, although there not as full as it could be with a full-range.

with 10k you might get enough butter to make a set of 20k speakers sing but I think you need to be frugal, watch the Gon for used jewels and be ready when something hits.

BTW I understand Mr. Polk is refusing to give Mark back the ARC pre and has left orders at his estate gate that he is barred entry to the island, the house can be accessed by water so a stealth black ops may be needed, however, he is on his own, I say let him keep the pre and move on.......

RT1

reeltrouble1

well I see I mispoke again in post 6. FTR the SL bass rises to 100 ohm, not 100K.

RT1

megasat16

reeltrouble1 wrote: »

yes, I have noticed a trend where hi-end electronics are being used with so-called mid grade speakers with rather grand results, a good example was the party at Matt Polk's some here went to, he had a hi-end Marantz SACD source, ARC tube pre (Doro's) and 1000 watt Threshold mono-blocks, hooked to a set of stock Lsi-9. Never heard the 9's sound so good, vocals hung just rights and these little speakers did fill the room with music, only thing negative I could say was the bass, although there not as full as it could be with a full-range.

with 10k you might get enough butter to make a set of 20k speakers sing but I think you need to be frugal, watch the Gon for used jewels and be ready when something hits.

BTW I understand Mr. Polk is refusing to give Mark back the ARC pre and has left orders at his estate gate that he is barred entry to the island, the house can be accessed by water so a stealth black ops may be needed, however, he is on his own, I say let him keep the pre and move on.......

RT1

Mr. Polk has an experience of a life time and whatever he has in his home, it probably cost him 1/10 of everyone's system but sounds 10 x better. It's just that his experience with synergy can't be compared with 100K worth of equipments. It's what I think a truly expert means. I am sure a few guys in CP are at this level but I am just a scratch on the skin at this stage.

The Threshold Big Monoblocs are very nice and they can handle any speakers. They are quite rare to come by too and I've seem them sold at the price tag near the Big Pass Labs Monos too.

I thought Doro's ARC pre was sold in FM. But if Matt's having a great time with it, it's probably he finds a good synergy with Doro's love.

megasat16

RT1,

Here is a nice pair of Threshold Mono...Damn, looks like 60+ BJTs (TO3) are used for each amp. I can only imagine the sheer output current of this thing.

I know you need a big A/C before the amp for this summer. But hey, it's free to take a look.

http://cgi.ebay.com/Threshold-Stasis-SA-12e-power-amplifier-MONO_W0QQcmdZViewItemQQ_trkparmsZ65Q3a10Q7c66Q3a2Q7c39Q3a1Q7c293Q3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZitem20ac599432QQitemZ140330505266QQptZLHQ5fDefaultDomainQ5f0QQsalenotsupported

cnh

So 12K for a pair? Not in my lifetime...but for those of you who have the coin! Go for it....I've rarely seen that much class A amplification...you can probably HEAT your house in the winter with two of those from all the excess energy used to generate those class A watts....but damn those watts sound...so.....good!

cnh

heiney9

cnh wrote: »

So 12K for a pair? Not in my lifetime...but for those of you who have the coin! Go for it....I've rarely seen that much class A amplification...you can probably HEAT your house in the winter with two of those from all the excess energy used to generate those class A watts....but damn those watts sound...so.....good!

cnh

BIN states $6K for the pr. and FREE shipping! They are Optical bias circuitry is a plus as well.

Notice they are 220V versions according to the markings on the boxes.

H9

megasat16

cnh wrote: »

So 12K for a pair? Not in my lifetime...but for those of you who have the coin! Go for it....I've rarely seen that much class A amplification...you can probably HEAT your house in the winter with two of those from all the excess energy used to generate those class A watts....but damn those watts sound...so.....good!

cnh

Yeah! A lot of coins for it but 250 Pure Class A Watts into 8 ohms.

They sounds so damn good when they works but Pure Class A needs thorough rebuilding when it's old. Thermal runaway shortens the life expectancy of the electronics components even for a good designed Pure Class A.

But for someone with coins to change the output tubes for the tube amp every two to three years, the cost associated to give a complete overhaul for a Pure Class A amp like this should be no problem.

heiney9 wrote: »

BIN states $6K for the pr. and FREE shipping! They are Optical bias circuitry is a plus as well.

Notice they are 220V versions according to the markings on the boxes.

H9

Yeah! Looks like they are 220V originally. I don't know if it's altered or not but the folks at Threshold should have kept record of the current ownership and the voltage conversion date if done by them.

6K is a fair price for these amps if it's not a scam. Notice there are two toroids in each monobloc? I think it's a modified design of dual monoblock into single bridged monobloc.

heiney9

A properly designed class A amp doesn't need anymore special attention or rebuilding compared to any other design. Now if the original designer cut corners, used inferior parts, etc. then yes, maybe.

That's not to say these amps don;t need a good going thru, but that would be from age not operating in class A. My Aleph get so damn hot in the summer I can't touch it for more than a couple seconds...........but I assure you the components inside are well up to the task of long term operatation in their intended environment.

The Optical bias helps keeps things stable and linear over the non-optical bias versions

megasat16

Yes, any well designed SS amplifier with quality components needs little attention and no rebuilding needed for a very long time. I have Class AB amps from 80s with all original parts and works flawlessly. But for Pure Class A amps, 25 years may be too long to wait.

I think a good Class A amp should last 10-15 years without much troubles. After that, the caps started to age and resistors are out of spec. I am rebuilding my Denon Class A POA-3000 amp currently and found it's 100 ohms resistors values have risen to 150 ohms or above and most electrolytic caps are in drying out. Anyway, it should have been serviced 10 years ago.

I think it's reasonable to give a complete overhaul or a thorough testing of Pure Class A amps after 10-15 years. Most people don't realize that fixing a broken amp is not the same as preventative maintenance. Unless a complete overhaul is given, there are more components which will go out of spec when heated and awaiting for another disaster.

But some technician would say why bother fixing something if not broken. It's true and false at the same time for (pure) Class A amp. I consider giving a thorough check and overhaul for Class a or really any amp is like you are changing oils for your car every 3000 miles.

Anyway, I think extra care should taken if purchased used Pure Class A amps and asking questions to seller when did the amp receive the last bench test seems a good start.

heiney9

megasat16 wrote: »

Yes, any well designed SS amplifier with quality components needs little attention and no rebuilding needed for a very long time. I have Class AB amps from 80s with all original parts and works flawlessly. But for Pure Class A amps, 25 years may be too long to wait.

I think a good Class A amp should last 10-15 years without much troubles. After that, the caps started to age and resistors are out of spec. I am rebuilding my Denon Class A POA-3000 amp currently and found it's 100 ohms resistors values have risen to 150 ohms or above and most electrolytic caps are in drying out. Anyway, it should have been serviced 10 years ago.

I think it's reasonable to give a complete overhaul or a thorough testing of Pure Class A amps after 10-15 years. Most people don't realize that fixing a broken amp is not the same as preventative maintenance. Unless a complete overhaul is given, there are more components which will go out of spec when heated and awaiting for another disaster.

But some technician would say why bother fixing something if not broken. It's true and false at the same time for (pure) Class A amp. I consider giving a thorough check and overhaul for Class a or really any amp is like you are changing oils for your car every 3000 miles.

Anyway, I think extra care should taken if purchased used Pure Class A amps and asking questions to seller when did the amp receive the last bench test seems a good start.

Sorry, but especially in the case of the high end class A amps I have to disagree. They are designed to run the way they are just like a well designed class AB is.

In my case high temp caps are used, more output trannies are used and are run at about 30% of their operating temp and all other components are high quality very rugged parts put in place to last.

I don;t understand why you think you need to overhaul or check out a class A design anymore than any other design (again I stress a properly designed and built amp like a Threshold or Pass or BAT or ML, etc, etc).

It's always good practice no matter what you buy to have it checked out if it's used and has had multiple owners, etc. That's smart for any piece of electronics, especially expensive pieces. But to say a pure class A won;t last as long is just not true unless there is a design flaw.

That's my .02c

H9

heiney9

megasat16 wrote: »

I am rebuilding my Denon Class A POA-3000 amp currently and found it's 100 ohms resistors values have risen to 150 ohms or above and most electrolytic caps are in drying out. Anyway, it should have been serviced 10 years ago.

I would almost bet 1st of all it's not pure single ended class A, 2nd Denon probably isn't built to the same standards of say a Forte, Threshold, BAT, Pass, Mark Levinson, Classe, Musical Fidelity, etc, so I would expect that it *might* need some work and that's regardless if it runs a bit in class A or not.

Not trying to say the Denon is junk...........but it certainly isn't on the same playing field as the above as far as parts quality and build quality.

H9

megasat16

heiney9 wrote: »

I don;t understand why you think you need to overhaul or check out a class A design anymore than any other design (again I stress a properly designed and built amp like a Threshold or Pass or BAT or ML, etc, etc).

It's always good practice no matter what you buy to have it checked out if it's used and has had multiple owners, etc. That's smart for any piece of electronics, especially expensive pieces. But to say a pure class A won;t last as long is just not true unless there is a design flaw.

That's my .02c

H9

I currently have ML 335 that undergone a good thorough check and recapped 3-4 months ago. I think most ML or Krell owners will tell you that their Class A amps had to be in the technician hands every 5-10 years due to one or two problems. I don't know about Pass or Threshold. I also have a few **** made Class A amps that needed repair during their 10-15 years life time. I think it's neither the design flaw or the use of lower quality components. I think it's that the electronics aging is faster with hotter amps.

Whether Pure Class A amps last as long as other Class A or Class AB amps depends on the design. But in general, Class A amps runs hotter than Class AB amps and thermal aging of components are faster in Class A amps.

Don't get me wrong. I am Class A guy myself.

megasat16

heiney9 wrote: »

I would almost bet 1st of all it's not pure single ended class A, 2nd Denon probably isn't built to the same standards of say a Forte, Threshold, BAT, Pass, Mark Levinson, Classe, Musical Fidelity, etc, so I would expect that it *might* need some work and that's regardless if it runs a bit in class A or not.

Not trying to say the Denon is junk...........but it certainly isn't on the same playing field as the above as far as parts quality and build quality.

H9

I quite agree that Denon is not the same as ML or Krell Class A amps. It's 25-30 yrs old designed and I have many Class A amps I've compared it to in terms of the Sound Quality.

It's SE push-pull Class A. I think most older Class A amps had been already serviced if they survived 25-30 yrs long.

heiney9

Well, you have your experiences so it's not really my intent to argue. Nelson believes quality caps have a life cycle of about 15 years some last longer some last shorter. He makes no distinction between being used in a class A or other design.

If you and I are still here in 20 years I'll let you know how the Aleph is doing. It has to be pretty rugged if you can short the outputs with no consequences :D.

I have absolutely no worries whatsoever that it will "wear" out any faster than my previous 23 year old Adcom. I'm that confident in the design and components used.

H9

heiney9

Well, see now your pushing the limit when you say 25-30 years. So yes after 25-30 years most if not all electronics will need servicing. I expect a well design amp to last 20 years with no major issues. My point in all this is just because it's pure class A doesn't mean it has a lesser life expectancy. Of course anything bordering on 20 years old or more will need refreshing.:rolleyes::D

cnh

heiney9 wrote: »

Well, you have your experiences so it's not really my intent to argue. Nelson believes quality caps have a life cycle of about 15 years some last longer some last shorter. He makes no distinction between being used in a class A or other design.

If you and I are still here in 20 years I'll let you know how the Aleph is doing. It has to be pretty rugged if you can short the outputs with no consequences :D.

I have absolutely no worries whatsoever that it will "wear" out any faster than my previous 23 year old Adcom. I'm that confident in the design and components used.

H9

That's good to know....nice give and take (and info) above. I've always liked the class A sound, probably my next upgrade...not immediate of course--I haven't even had a chance to get the SDA-2Bs up and running yet. And probably not in the 6K range....but whatever I can afford on the used market.

cnh

Systems

megasat16 wrote: »

I think it's that the electronics aging is faster with hotter amps.

True that,heat is a real enemy to the life expectancy of semiconductors .If a well engineered Class A design has sufficient heatsink area to keep the output devices within a reasonable temperature range then it should be as reliable as a good Class AB design.(assuming it's a reliable design to begin with).Capacitors have rated life cycles in relation to tempature.Caps rated at 105 deg C have longer usable life than those rated at 85 deg C.Most high end manufacturers opt for the 105 deg types.

megasat16

heiney9 wrote: »

Well, you have your experiences so it's not really my intent to argue. Nelson believes quality caps have a life cycle of about 15 years some last longer some last shorter. He makes no distinction between being used in a class A or other design.

If you and I are still here in 20 years I'll let you know how the Aleph is doing. It has to be pretty rugged if you can short the outputs with no consequences :D.

I have absolutely no worries whatsoever that it will "wear" out any faster than my previous 23 year old Adcom. I'm that confident in the design and components used.

H9

Computer Grade Big Electrolytic Caps have shelf life between 10-15 years. When they are used in a proper designed amplifiers regardless of Class A or Class AB, they should last somewhere between 10-20 years.

The life expectancy of the big caps depends largely on how hot their operating environment is. If a given cap has 3000 hours for 85 degrees C, it's life is shortened to 1000 hours if used in 105 degrees C. I think Manufacturer will provide that data with their caps.

Let's see if you use 2 hours a day at it's rated temperature of 85, it should last about 1500 days which is roughly about 3 - 4 years. But most amps will not allow you to run at 85 degrees C inside operating temperature so it'll be cooler for the caps and the caps life will extend considerable longer.

Class A amps are hotter (whether sitting idle or running) than Class AB amps so it's life expectancy (MTBF) can be calculated based on how the components aging effects the components used.

Anyway, what I said was just for the electrolytic caps and there are all sorts of other caps and other parts that are prone to thermal aging.

Ironically, my Denon amp works well and tested to putout full power sine wave sweep but it makes popping noise in one channel upon turning on and off. That's why I took it apart to start troubleshooting and found most electronic components values have shifted considerable. Even though it's not NP design, it's one of the most reliable Class A amp design I've seen.

I think it's a good sign there is components aging or some other issue exists if you measure DC offset of an amp and found it's more than 20mV, even if it's working and playing good.

Now about the Aleph you have, I think you don't have to worry about it's lasting 20 yrs or beyond since it's low power Class A amp. And NP had undoubtedly taken all considerations of thermal aging of components and had factored in the design for it.

But in general, I would say you should give any Class A amp a good thorough checkup or overhaul every 10-15 years no matter what happens to it. Even though there may not be a big issue, it's very likely the small things have already happened in 10-15 yrs.

heiney9 wrote: »

Well, see now your pushing the limit when you say 25-30 years. So yes after 25-30 years most if not all electronics will need servicing. I expect a well design amp to last 20 years with no major issues. My point in all this is just because it's pure class A doesn't mean it has a lesser life expectancy. Of course anything bordering on 20 years old or more will need refreshing.:rolleyes::D

No, Pure Class A don't have lesser life expectancy. It's just that they tends to sit on the Tech's bench more frequent than other designs regardless of how well it is designed. I know there are some but very few and limited number of Class A which can last as long as any other Class AB ones but many Class A amps do not fit in the bill including some of the NP amps. (duck)

I think the Threshold amps in discussion are about 10-15 yrs old and it's time it should be going for a thorough checkup. So, I want anyone who is buying it to consider about it or asking questions before buying. It's Class A amp so thermal aging of components will effect more or less due to how hard it's been pushed to it's limit and how well it was designed and what components are used.

megasat16

GV#27 wrote: »

True that,heat is a real enemy to the life expectancy of semiconductors .If a well engineered Class A design has sufficient heatsink area to keep the output devices within a reasonable temperature range then it should be as reliable as a good Class AB design.(assuming it's a reliable design to begin with).Capacitors have rated life cycles in relation to tempature.Caps rated at 105 deg C have longer usable life than those rated at 85 deg C.Most high end manufacturers opt for the 105 deg types.

You typed faster than me when I was trying to reply to H9. LOL

I think the things that goes out first in Pure Class A or Push Pull Class A (pseudo Class A) or Class AB amps are caps, resistors and such.

I tend to think that the output devices usually lasts longer and a well designed Class A amp with adequate heat sink or heat dissipating capacity will have the same kind of life expectancy as if it would be used in Class AB.

heiney9

If they are 10-15 years old they was probably little to no input from Nelson Pass. Not that it anyway means they are inferior, etc. If I had the coin I'd be all over them.

There are no adjustments of any kind in the Aleph and the only way it would end up back at Pass Labs is if something failed. It's a very hard amp to break. .

I completely get what you're saying and in my examples there are no absolutes and there are no absolutes in your examples.

I don;t believe a well engineered and well executed class A amp will spend any more time on the repair bench than an equally well designed other "class" design. Granted some of the older (15-30 year old) amps didn;t have the caliber of parts or the knowledge many newer designs have......so that could be the big issue.

Any class A amp worth it;s salt built and designed in the past 10 years or so shouldn;t be any less reliable than other types of "more" efficient designs if executed properly.