Thank u so very much,like tubes,but these mosfet power amplifiers seem more efficent (no $$ high price tube to replace)

 :)Hi All
i am using a Carvin Quad x-amp (9 tube preamp) and a Smart TA 242 Mosfet power amplifier,this is a power amplifier used in Movie Cinemas,and they were based on a Hafler 220 power amplifier,but way more power (+/- 65 v dc)i am wondering if anybody else use similar set-up

Peace
Dusk

Hi Enzo

I have the Bandit 2 with the red stripe and block Peavey" bage" (made in USA),and it's a great amplifier imho,full of nice tones.

Dusk :dbtu:

Thanks J M Fahey
One more question,are these diode mounted on the driver heatsink ?

Oh thanks you also Roly,for the input too.

Dusk

Hi All
can anybody tell me how Peavey stop thermal run-a-way in their Transtube Amplifier power stage,do they use an vbias transistor circuit??

Dusk

Hi JM Fahey

I have only played the Mosvalve 962 through the 2x12 cabinet,it still lacked bass,mind you i did't krank it.
I have a Fender all-tube bassman 100watt,i played with the Peavey 112 cabinet,plenty of bass.

Dusk

One More Pic


Dusk

Hi JM Fahey

Yes,very sweet
Dusk

HI All
Here are some pic of my rig

Dusk

Hi Folks
This is what the orginal post was about,i have two Tube Works amplifier :RT2100and Mosvalve 962 and i said i could not understand why they lacked bass respones (imo). I wanted to know why,i use a Peavey 112 close-back speaker cabinet rated at 75-80watt with these amplifiers.

Dusk

i removed the orginal to try to correct some typing erro , as you can tellim not a born key board  wis ,i tried to get the orginal back but no luck.

Hi  JM Fahey
It has feedback but it's from the driver transistors, that drive the output mosfets, from the driver transistor the feedback goes back to a input IC chip(TLO 71...?)and not from the output side(mosfets).
Yes, i have a schematic for the Mosvalve 962,but not for the RT2100. The problem is ,my scanner is a Windows 98 type and my system is Windows Vista and the two cant' shake hands...i don't think(i will get a new scanner soon...money$$##).
My speaker iam using with these units, is a Peavey 112 Bandit Extension cabinet rated 75-80 watts,it is close-back.
The RT2100 has two 12ax7s in it's preamp sectionthere are no tubes in the Mosvalve962
Dusk
 ps i have a rack system that has Paia  stack in abox tube preamp that feeds a Hafler P-500 mosfet power amplifier
that driver a homemade 2x12 close-back cabinet 280watts or so rated modo bass there.....also sorry for the bad typing.

......Oh

I just reread your reply on the Slone Optimos amplifier.I don't have any Pspice simulation...i would not know how to even use it......but you say it shows that the Optimos is closer to soft-clipping than the Opto/fet limiter circuit....mmmh maybe i should just get a pc board of the amplifier and make one.....you say it really round thepos and neg output....and you can see this with that simulation you have? I only use tube preamplifier with my power amplifiers,i have a Hafler pro-500watt power amplifier/250per side....i know this is overkill but the Hafler is the same type of circuit symmetrical differential input but not the  same VAS cascode that Slone use

Well....mmm

I noticed that in the http://www.picks.force9.co.uk that the max input is 3mvrms and max is 2.6rms,now this unit would be placed between the output of the preamplifier and theinput of the power amplifier....ok, with it's input andoutput rms voltage would the limiter componet have to be changed....remember ....iam not an Amplifier Guru


also i have seen adiscreet transistor rig to the output of a ss (guitar)amplifier. It was tired to the input differential somehow to mimic a high impedance output i think i saw a ESP web site on a 100watt (diy)guitar amplifier...don't really know how it worked

as alway THANKS

THANKS

Yes
I see you havedone your homework on this ....i alway hear about how ss amplifier don't compare with tube amplifier as far as overdrive sound. I am always wondering way not eliminate the bad overdrive in ss units by using limiter and using tube pre-amplifiers to get the so-called tube overdrive...i see Marshall has an the Mode Four this is  hyrid amplifier tube/ss power amplifier 350watt i have heard it and too me it sound good imho,but people say it's not power tube overdrive.....beats me? by having a Chip amplifier  for an output you save on power tube replacment.
The Acoustic amplifiers you mention i know that the great Albert King used them in the 70's and80's and to he sounds great..a non-amplifier GURU

PS
i Know that you could use a variable pot to set the input level on limiter  on the input of the power amplifier....you would not have to worry about different ohm speaker or wattage levels......Thank

Ok
This one.....seem that you have to keep making ajustment for different output wattage andspeaker ohm impeadance.......is there one that just reduces the input gain.... without reguard to speaker impedance or output wattage......iam more of a guitar player than amplifier GURU.......THANKS for all the info

ps i have noticed that more Bass (ss amplifier) use limiter..why is that?..seem like guitar amplifier (ss guitar amplifier would need this limiter more?

againTHANKS