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Looks like they have another big hit on their hands.
"Familiarity breeds contempt, and children."
-Mark Twain
Follow Ups:
Class-G to replace the tooobys and no clipping .... :)
Thanks for the Tech info, I note the Arcam does contain mos-fets which are OK in a good design, I see no mention of FETs which I definately do not care for.
Dis,
MOS fets are a type of FET.
Take it from a guy who worked in a discrete wafer fab for 15 years as a process guy.
You may have some objection with JFET devices, which I believe predate the MOS variety.
And while the WIKI, should you care to look, references the 'body' contact, the devices I'm most familiar with are the HEXFETS which use the 'bottom' of the transistor as the 'Drain' connection. The Gate and Source are from the TOP.
Too much is never enough
Thanks for the info of course it is the JFETs that I do not like. Mos-Fets are good.
I would never buy an amplifier containing JFETs and am not too keen on mos-fets either.
Seriously, now you are discounting solid state devices as well as tubes??? That leaves you with just bipolar transistors...doesn't it?
Surely you cannot be serious that in your opinion ONLY bipolar transistors sound good in a circuit??? The LEAST linear of ALL amplification devices is your device of choice...LOL!!! Whatever floats your boat but it sure is a strange boat you are in.
Go and audition the Arcam A49 .
Oh yes I am just dying to try an amp from a company where a Senior engineer is quoted:
"We considered having a volume control that went up to 11 - it really goes THAT loud!"
Whooo hooo!!! LOUD baby! Not sophisticated, not natural, not tonally accurate but LOUD¨!! Yeah!
Plus, they lie about the first 50 watts being a Class A amplifier:
"The A49's output stage includes a proprietary error correction circuit that modulates the modest standing currents in the
output stage and ensures a near-constant output impedance for peak currents of up to about +/- 4 amps, corresponding to well over
50W in to 8 ohms. The A49 thus behaves exactly like a classical class A amplifier up to this power level in terms of performance
but without the heat penalty."
At best, it is a sliding Class A but for sure it doesn't have the heat sinks to maintain true Class A at 50 watts and it only consumes 220 watts for 50 watts output...this is far more efficient than true Class A and so there is no way this is really Class A...more marketing hype.
What is your point? It uses MOSFETs on the output. Do you like this amp or not? You just said you don't really like FET amps and then you want me to hear this amp, why?
It looks like it measures ok and even the distortion spectrum looks pretty good...but only listening tells the whole story.
Yes I find the Arcam Class G amp sounds very good otherwise I would not have bought one.
Replacing, Job and then Rotel, more of the same...
Not more of the same Arcam G tech is superior to the Rotel & the JOB 225, you should listen to the Arcam before commenting on something you have not auditioned otherwise your comments are valueless.
Let's see, small sliding bias...check (been there done that). Rail switching...check (been there done that). Marketing hype galore...check check check. The technical superiority is debateable and even if it were the case it would be irrelevant to listening. I will listen to it someday if I can be bothered but having heard dozens of similar amps I won't hold my breath for glory. I might even know a local dealer who has it...but if you can't hear what is wrong with these designs...well I guess it is a blessing for you.
I have looked up cross sections of JFET and MOSFET transistors and I can pretty much guarantee that a fab set up for ONE could also manufacture the OTHER. All the layers, materials and dimensions look familiar from my days making HEXFETS. And IGBTs and FREDs. Not to mentions several experimentals I was involved in which never made it to production.
The stuff I worked on had the bottom of the die used as the drain. The gate and source were both connected from the TOP. I'll not get into any proprietary information, but the parts I worked on were very simple in that they had a minimal number of mask layers and some 'self aligning' features which also take the place of additional masking / photo / etch steps.
The bottom of the die as drain made good ohmic contact which gave a very LOW RdON. Resistance of the device when ON. For an audio amp? I suspect it helps keep DF low.
The difference, as they exist would need a curve tracer to fathom.
Too much is never enough
Did you work with Wurcer ...... ??
Wurcer who?
Sorry, not in my memory bank.
Too much is never enough
Mr IC himself ........... :)
Sorry,
Never worked for Analogue Devices.
By the time I happened on the scene, say '73 or so, the fab I worked in was ALREADY a 3" fab which later upgraded to 4" or 5" silicon. The reason that's important is COSTS. It only costs a LITTLE more for processing 6" silicon while the OUTPUT in useable devices is nearly 4x that of a 3" wafer.
Later, at Western Digital (think hard drive) we built an All-New 6" fab which was an incredible machine.
Same work w/4x the output. What's not to like? Equipment is more expensive, but that's written off over time. Talk to the tax / accounting types for THAT aspect of the business.
Too much is never enough
Nope, it also leaves him with IC's , he may like the sound of chip amplfiers.....
But aren't those just a collection of bipolar (or maybe they have FETs as well) transistors? Sure, its operating as a collective but it is still made of discrete transistors of some kind. For small signal opamps, some have bipolar, some have fet, some are mixed but for the power chips I don't know what is inside.
That rules out some of the very best preamps and power amps available.
Good choice!
No J-fets, No MOSFETS, no TOOOBS , Electricity , well maybe ...:)
No J-fets for disbeliever ....., i bet it wipes the floor with the Rotel . Lol ...
Very unlikely
Likely or NOT?
I had an RB1070 which I must say is much inferior to my A23(s)
The RB? NO 4 ohm power rating and the bridged mono of 330 implies a 4ohm rating which WOULD be 165x2 with 8ohm power at 125 or 130 a side. Not too indicative of a robust PS.
Too much is never enough
Also had an RB 1070 and it was inferior to the Harman/Kardon HK 3485 receiver it replaced. And that was with easy to drive speakers.
I have only referred to the Rotel 1552 Mk 2 amplifier amplifier, other models are totally irrelevant, read the Absolute Sound review.
Picture Guy, The Rotel 1552 Mk2 has a large case is very heavy for a 120 wpc Class AB amp, sounds very good therefore surely has a good power supply , I agree 4 ohm figure is not specified . It is not as smooth at HF as the far more expensive amps but still very acceptable as mentioned in the Absolute Sound review. I have yet to hear an amp with JFETs that I can listen to.
Edits: 03/09/15
Tomato amp vs. Pass Labs XS series.
Yeah, that's a tough one!
ROFL ...!!!!!
Arcam uses Mosfets, Disbeliever must be sick by now ... :)
Not a big Rotel fan , the last ones heard were used by a friend to run ML, they would shut off ( class-D) after 45 mins , pretty pricey too.
Regards...
Arcam uses Mosfets, Disbeliever must be sick by now ... :)
Yeah the multi-rail "lifters" are MOSFETs. :)
You should get one disbeliever and step away from the Rotel......
Based on his post above, it sounds like he did get one...wonders never cease...he wouldn't touch FETs with a ten foot pole and then, lo and behold, he buys an amp with MOSFET outputs!! But that is OK, because the aren't JFETs you know...LOL!
Reading the Arcam technical paper on the Class G A49/P49 amplifiers it states the output transistors are Bi-polars ,mos-fets are just used for very fast switching.
You are right about the output transistors...I didn't see the specifics the first time I scanned through the technical white paper.
Had a strange experience with the mos-fet JOB 225 sounded very good with an Aurousal VS speaker but I did not like it with the latest updated version Acoustic Insight Phantom Source Floorstander. Fortunately the Arcam P49 with mos-fets sounds excellent with the PS.
Reference 3a does something similar to these AI drivers by tailoring the shape of their driver so that there is no appreciable breakup mode and they can then run them flat out without crossover. They use doped woven carbon fiber though rather than metal. They call their profile hyper-exponential...like a horn flare actually.
Sounds like competition for the reference 3a ...... :)
Unusual speakers...never heard of them before. ARe the Jordan drivers run flat out (i.e. no crossover)? It doesn't really say in the description, which if stuffed full of hyperbole.
If both Jordans are run full range then isn't there going to be cancellation issues making a combing effect? They don't look close enough and there are not enough of them to make an actual line source.
Phantom Source Floorstander TL speakers incorporate Jordan Eikona 2 full range drivers manufactured by Scanspeak,no Xover sound excellent TL cabinet design by Martin J King Quarter Wavlength Design
Edits: 03/10/15 03/10/15 03/10/15
Sorry.
No sale. The utter lack of any 4 ohm disclosure is to me, a red flag. Not even a rating for 8 ohm 'bridged' from which you could INFER the 4ohm power at 1/2 that rating. And as for weight? It is within range of the A23. In looking at the PICS of A23 vs the Rotel, It APPEARS the Parasound has a SLIGHTLY beefier tranformer. I'd love for rotel to disclose the VA rating of THEIR transformer.
As for JFETs? another chat for another day. I WILL say that if you were confronted with an unknown amp, and ONLY had its 'signiture' to go on, you'd have only probability to get your choice right.
Too much is never enough
The sound is more important than the spec.
Sure, but that cuts Both Ways.
If you can't, in blind tests identify a JFET, than so what if it HAS 'em?
And likewise, the Rotel RB-1070 was so poor at driving my panels that I couldn't WAIT to get it out of there. A 300$ lesson. Just no DRIVE.
I suspect that had I ponied up for the RB1080, that may have stuck around for YEARS or even still be in service.
Too much is never enough
...how good is the phono section ?
I note with interest the responses below that call this unit "good looking". You can't argue taste, but to me its kinda' boring looking, bordering on ugly.
Dean.
reelsmith's axiom: Its going to be used equipment when I sell it, so it may as well be used equipment when I buy it.
I have a P-5, but it's my return to two-channel, and phono, so I don't really have a basis of comparison. Having said that, the MM section is sounding great to me and it got a glowing review in Stereophile. The MC section was not as well regarded in that review.
the integrated contains a P 5 preamp and a power amp sort of like the A23. Art reviewed the P 5 (see link) but didn't answer my questions at the end ...? I was pretty disappointed in his review (not the preamp, his methodology etc.), it seemed to lack thought about what he was doing with the preamp.I got a P 7 instead, haven't even tried the phono section yet.
Edits: 03/09/15 03/09/15 03/09/15 03/09/15 03/09/15
never mind ...
Edits: 03/09/15
So how much does this big hit cost?
.
marc g. - audiophile by day, music lover by night
I really like the look of this amp. I'm not giving up my Rogue Cronus Magnum for it, but if I were in the market I'd seriously consider a purchase.
Thanks for the post.
Keep wishing Parasound would make the volume knobs larger on their recent preamps and integrateds.
IIUC, it IS the P 5 preamp (not a simplified version of it) plus ... ??? something between an A23 and A21 amp. Tasty!
Looks like they actually updated the DAC portion. It can do DSD decoding, which my P5 cannot. If this had been available when I picked up my P-5 and A-23, it would've been hard not to go with it instead.
ah, shoot. Oh well, you can still upgrade the pre and amp separately sometime. Wonder if they could update the DAC in the P 5? Probably a surface mount device ...
Opus 33 1/3
Probably held up cause of the dock strike. Don't blame the Chinese, they would be happy to make 1/16 of a long shore man's salary.
Cant' we keep racist insults out of your discussions of amplifiers!
ain't working.
Opus 33 1/3
He's found the chink in your armor? Sorry, couldn't resist...[g]
-RW-
Oh God, help me, but I can't resist either. "Chink in the armor" RoR
Isn't Parasound stuff made in ROC (Taiwan)?
If I ever wanted to simplify this would be a contender.
Very nice looking gear.
This new Parasound integrated amp looks so tempting. Unfortunately I purchased a new tube amp and preamp last year.
N/T
"Once this was all Black Plasma and Imagination" -Michael McClure
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