| Author |
Topic: Anyone play thru a blackface twin? |
Tim Greene
From:
Athens Tennessee USA
|
Posted 7 Dec 2010 8:05 am |
|
| Does a properly serviced blackface twin stay clean at higher volumes or will they breakup/crunch.At what setting on the volume should they breakup or do they? Thanks Tim |
|
|
 |
Darrell Owens
From:
California, USA
|
Posted 7 Dec 2010 9:46 am
|
|
I have a '69 twin with JBLs, and your ears will blow out before it will break up.
_________________
Zum Steel, Little Walter Amp, Benado Steel Dream
Darrell Owens
www.darrellowens.com |
|
|
|
Scott Swartz
From:
St. Louis, MO
|
Posted 7 Dec 2010 10:52 am
|
|
+1 , if you need more clean headroom than a Twin Reverb, you had better be wearing earplugs.
Noticeable breakup starts at maybe 5 on the volume knob. 4 on the volume will hang with a loud drummer and a guitar player with a cranked 30-40 watt amp in a rockin' new country type gig.
_________________
Scott Swartz
Steeltronics - Steel Guitar Pickups
www.steeltronics.com |
|
|
|
Tim Greene
From:
Athens Tennessee USA
|
Posted 7 Dec 2010 1:06 pm
|
|
| Mine starts to breaks at 4 on the volume knob with my steel.Is that where a blackface twin will breakup or should it stay cleaner ie more volume before it breaks. Tim |
|
|
|
Scott Swartz
From:
St. Louis, MO
|
Posted 7 Dec 2010 1:36 pm
|
|
Clean volume depends on lots of things
-Output tube condition and bias point
-Preamp tube choice (5751 or 12AY7 gives more headroom)
-How efficient are your speaker(s)
_________________
Scott Swartz
Steeltronics - Steel Guitar Pickups
www.steeltronics.com |
|
|
|
Tim Greene
From:
Athens Tennessee USA
|
Posted 7 Dec 2010 2:25 pm
|
|
| Scott I have a 1967 blackface w/jbls I got last week that brokeup at 4 on volume.Stock original except for power caps but not sure of their age.I installed new 6L6eh power tubes,changed resistors on tube sockets(talk about drift),checked voltage vs schematic and set bias.Used different speakers but still got the early breakup.Have new power caps ordered to install just to be safe.I hope its the power caps as I thought even thought its a blackface twin it would have more clean headroom than it does. |
|
|
|
Ken Metcalf
From:
San Antonio Texas USA
|
Posted 7 Dec 2010 2:53 pm
|
|
25 watt green back Type (Celestions) will break up earlier.
50 watt (Weber) speaker and up will have more head room.
I like the 25 watts in a 2-12 Twin and 50 watts in a Deluxe.
_________________
MSA 12 String E9th/B6th Universal.
Little Walter PF-89.
Bunch of stomp boxes |
|
|
|
chas smith R.I.P.
From:
Encino, CA, USA
|
Posted 7 Dec 2010 4:10 pm
|
|
| I have a blackface and a silverface 135. The 135 is clearly superior. |
|
|
|
Ken Fox
From:
Nashville GA USA
|
Posted 7 Dec 2010 8:05 pm
|
|
Try the #2 input, that will pad the steel pickup's output down before it hits that first tube gain stage. Other than that you can play V2 and change it to :
12AT7 gain of 70
12Ay7 gain of 45
12AU7 gain of 29
Just remember that pickup goes directly to a tube first, not to the volume control. Therefore if it is too hot it will overdrive any tube you put in there. That is why there is a second input that is padded down. |
|
|
|
Scott Swartz
From:
St. Louis, MO
|
Posted 7 Dec 2010 10:00 pm
|
|
What plate voltage on the power tubes are you getting?
If you have an oscilloscope, I would inject a 1 kHz sine wave and see what stage of the amp the distortion is occurring.
Also check if you are getting 80 watts output at the speaker with the sine wave.
At 4 ohms, 80 watts will be about 50 volts peak to peak on a scope, or about 18 Vrms on a DMM, assuming your DMM reads accurately at 1 kHZ (many do not).
I am sure you are aware a Twin will never be as brutally clean as SS amp.
_________________
Scott Swartz
Steeltronics - Steel Guitar Pickups
www.steeltronics.com |
|
|
|
Tim Heidner
From:
Groves, TX
|
Posted 8 Dec 2010 12:04 pm
|
|
| I just went through the high/low input thing with my Hiwatt clone a few weeks ago. Steel pickups are too hot for the high input. |
|
|
|
Tim Greene
From:
Athens Tennessee USA
|
Posted 8 Dec 2010 1:40 pm
|
|
| Scott Plate voltage 465 dc and I wish I had a scope and a esr meter but I dont.Changed power caps last night to sprauge atoms and the amps still want to break up but now around 5 on volume.I guess I will try to sell it as I have 3 twins,a showman and a revelation rack with a boogie 2 ;90.Thanks for all the replies Tim |
|
|
|
Ken Fox
From:
Nashville GA USA
|
Posted 12 Dec 2010 3:43 pm
|
|
| If you have a plate voltage of 465 on a Blackface then I suspect your bias is way to low. You need to check the bias for sure, that could account for the early distortion. |
|
|
|
