ADA Depot - A Forum To Support Users of ADA Amplification Gear

Let's Get Technical => Power Amp Tech => Topic started by: jarrodthebobo on January 16, 2014, 08:22:42 PM

Title: Re: CARVIN TS100
Post by: jarrodthebobo on January 16, 2014, 08:22:42 PM
Well once ah get my Carvin Ts100 in (and buy a crap ton of new chords for all of this stuff...) Ah'll give it a try!

However, the model Ah've purchased was said to have a volume issue on one channel, but the other is fine. Said it was quieter than the other. Does anyone know why this might be? Ah was thinking of using it bridged 90% of the time so Ah just went ahead and bought it anyways, hahah!
Title: Re: CARVIN TS100
Post by: rnolan on January 16, 2014, 10:47:22 PM
The TS100 is a good amp, that's what I'm using at the moment.  You wont need to use the presence knobs at all, they are a nice clean amp and the 50w a side is plenty (a bit like Marshall watts  :thumb-up: ).  Channel volume issues could be a variety of things, volume pot may need a clean/spray with contact cleaner (as may input/output sockets), input tubes may need changing (how old is it ?), output tubes may need changing, maybe miss match of the output tube selector switch (you can switch between EL34 (6CA7) tubes British sound, and 6L6 tubes US sound) although this would affect both channels.  Mine has 4 nice groove tube 6L6 tubes (it came like that), I would have preferred EL34s but the 6L6 tubes are fine as it's transparent, no added colour (also my preference).  There are 4 12AX7 tubes for the input (1 gain 1 buffer per channel, Dougs Tubes had some advice regarding different input tube selection) and 4 EL34 or 6L6 tubes for the output (2 per channel in push pull).  The output tubes on the softer channel may need bias adjustment (this is the point where the tubes swap ie one tube does the  ve part of the signal, the other the -ve part, bias (predominantly) gets that xover point right).  If one channel has issues I wouldn't use it (bridged or otherwise until you get it fixed).  Be a shame to run it bridged when it will sound so much better in stereo.
Title: Re: CARVIN TS100
Post by: jarrodthebobo on January 17, 2014, 04:32:03 AM
Thanks for your input man! The only thing about stereo that will bother me is the fact that Ah'll need to get so many more cables now! hahaha! Ah've used up all my patch cables for what Ah have already, so yeah  :lol:

Ah'll be sure to check out the bias of the Carvin when it arrives, or check to see if the tubes seem to be operating correctly..

Honestly though, Ah may not even need to run it bridged as ah've heard this unit is rather loud as it is, but if it is so much better in stereo then Ah could be at a loss do to the loss of output in channel A... hmmmm... hopefully it can be resolved.

(http://i.ebayimg.com/00/s/MTAwMFg3NTA=/z/HT0AAOxyVLNS01d3/$_57.JPG)

A picture of the unit, if that'll help.
Title: Re: CARVIN TS100
Post by: rnolan on January 17, 2014, 08:55:39 PM
Hey Jarrod, happy to help  :thumb-up: .  From the pic I would guess it has EL34 output tubes (UK sound (ish)), when you power it up, check they are all glowing nicely (both input and output tubes).  Just behind (to the right) the input tube (bottom in the pic) you'll see a switch, that selects EL34 or 6L6, the bias trims are around there also.
Yeah they have lots of grunt for a 50w p/chan amp. Also versatile in that you can select between 16, 8 and 4 ohm speaker loads.  I currently run into 2 16 ohm 70w celetions, one per channel (old(er) ADA split stack wired stereo).  16 ohm speakers are more efficient so it kicks....  For bigger shows I take my other 2 split stacks instead loaded with 90w boogie celetions 4 ohms each box
Title: Re: CARVIN TS100
Post by: jarrodthebobo on January 17, 2014, 09:26:02 PM
Alright when she  arrives Ah'll make sure the switches are set for their correct bias's and maybe throw a new set of tubes in her just in case.

Is it possible to run 2 el34s in one side and 2 6l6s in the other and run them in bridge? Ah've seen and heard others do this and they say it sounds great in the ts100, but ah didnt want to try it if it could potentially harm the amp!

Thanks!
Title: Re: CARVIN TS100
Post by: rnolan on January 17, 2014, 09:46:44 PM
Hey Jarrod, I wouldn't mix and match like that, BAD idea.  While the valves do similar things the pin assignments are different (grid 3 is on different pins).  The switch in the TS100 (and there's only one switch) changes the pin assignment to accommodate the grid 3 pin difference (and probably other things as well).  So to make it work, you'd have to modify the connectors to the valve sockets and not use the switch (for one channel). Also one is a tetrode and the other a pentode.
Cheers R
Title: Re: CARVIN TS100
Post by: MarshallJMP on January 18, 2014, 06:16:29 AM
A 6L6 is not a tetrode but a beam power tetrode,there is a big difference.Tetrodes are actually not really suited for audio,these are mostly used in transmittors in class C.

http://en.wikipedia.org/wiki/Beam_tetrode
Title: Re: CARVIN TS100
Post by: jarrodthebobo on January 18, 2014, 09:22:49 AM
Alright so ah'm gonna just go ahead and assume the people who've plated with both tubes going blew up their amps then haha  :lol: .

Alright, probably gonna stay with the el34s then
Title: Re: CARVIN TS100
Post by: rnolan on January 18, 2014, 06:59:28 PM
Doug's has some EL34s at a good price (http://www.dougstubes.com/mullard-el34.html) ($22.95). Although Carvin say you can individually bias each channel and have different valve pairs (http://www.carvinworld.com/products/TS100) but should only run this in stereo (not bridged) Manual attached.  So there must be 2 valve selector switches, I can only see one in the pic and I only remember there being one when I opened mine up (but that was a while ago).  Anyway I still wouldn't do it (and you can't (shouldn't) run it in bridged mode with different pairs).  I've attached a schematic and an article on biasing carvin amps.  Although the manual gives reasonably detailed instructions for biasing the output tubes.
Title: Re: CARVIN TS100
Post by: rnolan on January 18, 2014, 07:00:28 PM
Biasing Carvin Amps attachment
Title: Re: CARVIN TS100
Post by: rnolan on January 18, 2014, 07:39:10 PM
A 6L6 is not a tetrode but a beam power tetrode,there is a big difference.Tetrodes are actually not really suited for audio,these are mostly used in transmittors in class C.
Thanks MJMP, Interesting read  :thumb-up:
Title: Re: CARVIN TS100
Post by: Dante on February 12, 2014, 05:14:23 PM
Hello Gentlemen,

I noticed this thread was getting a bit off topic  ::)  So, I moved it into a section more appropriate and changed the title. This was previously: Re: Which cabinets do you use?

I thought the new subject line might help you later, when scouring the web for information on a TS100  :thumb-up:
Title: Re: CARVIN TS100
Post by: rnolan on February 12, 2014, 10:33:57 PM
Good idea Dante  :thumb-up: