Let's talk about the Ashdown Little Bastard

[monsterthompson]

Question on the LB30its 30 watts at 8 ohms, so is it close to 50 watts @ 4 ohms

No. That "doubling" only happens with solid state amps. Tube amps like this will have a 4 Ohm output jack and an 8 Ohm output jack, and each is 30w.

 

[Wasnex]

Question on the LB30its 30 watts at 8 ohms, so is it close to 50 watts @ 4 ohms

No. Tube amps provide the same power as long as they see the expected load. So the amp expects either 4 ohms or 8 ohms...and makes 30W at both.

This is achieved with an output transformer with two output taps. The main thing the transformer does is match the very high output impedance of the tubes to the low input impedance of the speaker.

The 8 ohm output tap provides more voltage but less current. The 4 ohm tap provides more current but less voltage.

Ohm's Law Formula Wheel

Let's find the current (I) using this formula

and the voltage (V) using this formula

30W at 8 ohms
I=sq rt (30/8)=~1.94A
V=sq rt (30x8)=~15.49A

30W at 4 ohms
I=sq rt (30/4)=~2.74A
V=sq rt (30x4)=~10.95

I used ~ to indicate rounded figures.

To prove we will use this formula for power (P):

At 8 ohms using the Voltage and Current we derived above
P=1.94x15.49=30.05W

FYI, the extra 0.05W is a rounding error.
​

At 4 ohms
P=2.74x10.95=30.00W

As you see, the Voltage and Current change, but the power remains 30W regardless of 4 or 8 ohms.

 

[BassBeginer64]

ok so either a 8 ohm or a 4 ohm speaker cab will sound the same then, kinda was hoping to get more volume out of a 4 ohm

 

[Wasnex]

ok so either a 8 ohm or a 4 ohm speaker cab will sound the same then, kinda was hoping to get more volume out of a 4 ohm

You might get less out of a 4 ohm cab if it uses a single driver. Why? 4 ohm drivers are often 1-2dB less efficient than 8 ohm drivers.

 

[monsterthompson]

26432163[/URL], member: 330176"]ok so either a 8 ohm or a 4 ohm speaker cab will sound the same then, kinda was hoping to get more volume out of a 4 ohm

The tube amp design and function is a holdover from an era when it was more likely that you’d have a single 8 Ohm cab or a pair of 8 Ohm cabs for higher volume needs. The idea of maximizing watts by using a 4 Ohm cab with the same size and/or number of driver(s) as a similar 8 Ohm cab is a more recent development.

 

[Dynacord]

ok so either a 8 ohm or a 4 ohm speaker cab will sound the same then, kinda was hoping to get more volume out of a 4 ohm

The one thing I've done which seems to get more volume out of it (Little Stubby in my case) is using a high pass filter.

 

[Joris 55]

ok so either a 8 ohm or a 4 ohm speaker cab will sound the same then, kinda was hoping to get more volume out of a 4 ohm

It seems like you've already gotten some excellent advice! To get more volume out of it, you could also try adding some more speakers, but headroom isn't really the point of these amps.

 

[Nuage420]

For Sale - Ashdown Little Bastard

need to move my LB kinda quick shoot me an offer I'm likely to accept it!

 

[TonetotheBone]

Hi all,

I’m the proud owner of a 20th Ann. Ltd. Ed. CTM-30 in tweed, with a matching 112T-250 cab I use as a monitor. It’s a handsome little rig! But the thing is the knobs aren’t cream-colored chickenhead knobs, as they are in every photo of this particular version of the amp I’ve seen. Instead it has straight black knobs with a circular base and white line. I checked, and it has the choke for instance, so the only thing unusual about it (for a tweed) is the knobs.

I think I’d like to switch to the “normal” cream chickenheads, because (1) they’re much easier to see in low lighting conditions, (2) they don’t come as close to the switches between them (and so are harder to bump), and (3) they’re more authentic looking on a tweed amp. But to this end I have a few questions:

1. There’s no set screw in the stock knobs. So do I just pull them off?
   
2. As this version is made in the UK rather than China, I assume it has quarter-inch shafts? (Will I need a shim?)
3. Should I just buy the knobs from Fender (perhaps via a seller on Amazon), or does anyone know of a better place to get them? I’ve seen a few different brands & styles of “chickenhead” knob floating around on the Internet, but I’d like to have the same ones Ashdown uses on other copies of this amp.

FWIW, the shade of the amp’s tweed is slightly different from that of the cab (it’s a little grayer, almost greenish). I suspect this may be one of the last of its kind Ashdown built, and that’s why it uses different tweed / knobs. I bought it from their website directly, for only about 900 USD including the cab and shipping — which was a pleasant surprise, given that the Little Stubby for example retails at major outlets for a thousand and a half with no cab! It took them a few weeks to get around to shipping it, but once they finally did it arrived in just a few days. Maybe they actually built it for me last minute, from leftover parts? I don’t know; but it is brand new, and (so far) unmodified. The knobs just aren’t what I was expecting, is all.

I’d appreciate any observations or tips you may have. And if there’s anything else you need to know, just ask. Cheers!

 

[foal30]

I don’t know about Chickenheads sorry

But $900 US sounds a sharp price for Amp and Cabinet

 

[Joris 55]

Hi all,

I’m the proud owner of a 20th Ann. Ltd. Ed. CTM-30 in tweed, with a matching 112T-250 cab I use as a monitor. It’s a handsome little rig! But the thing is the knobs aren’t cream-colored chickenhead knobs, as they are in every photo of this particular version of the amp I’ve seen. Instead it has straight black knobs with a circular base and white line. I checked, and it has the choke for instance, so the only thing unusual about it (for a tweed) is the knobs.

I think I’d like to switch to the “normal” cream chickenheads, because (1) they’re much easier to see in low lighting conditions, (2) they don’t come as close to the switches between them (and so are harder to bump), and (3) they’re more authentic looking on a tweed amp. But to this end I have a few questions:

1. There’s no set screw in the stock knobs. So do I just pull them off?
   
2. As this version is made in the UK rather than China, I assume it has quarter-inch shafts? (Will I need a shim?)
3. Should I just buy the knobs from Fender (perhaps via a seller on Amazon), or does anyone know of a better place to get them? I’ve seen a few different brands & styles of “chickenhead” knob floating around on the Internet, but I’d like to have the same ones Ashdown uses on other copies of this amp.

FWIW, the shade of the amp’s tweed is slightly different from that of the cab (it’s a little grayer, almost greenish). I suspect this may be one of the last of its kind Ashdown built, and that’s why it uses different tweed / knobs. I bought it from their website directly, for only about 900 USD including the cab and shipping — which was a pleasant surprise, given that the Little Stubby for example retails at major outlets for a thousand and a half with no cab! It took them a few weeks to get around to shipping it, but once they finally did it arrived in just a few days. Maybe they actually built it for me last minute, from leftover parts? I don’t know; but it is brand new, and (so far) unmodified. The knobs just aren’t what I was expecting, is all.

I’d appreciate any observations or tips you may have. And if there’s anything else you need to know, just ask. Cheers!

All I know is, I'm not buying any of this without a couple of pictures

 

[Wasnex]

Hi all,

I’m the proud owner of a 20th Ann. Ltd. Ed. CTM-30 in tweed, with a matching 112T-250 cab I use as a monitor. It’s a handsome little rig! But the thing is the knobs aren’t cream-colored chickenhead knobs, as they are in every photo of this particular version of the amp I’ve seen. Instead it has straight black knobs with a circular base and white line. I checked, and it has the choke for instance, so the only thing unusual about it (for a tweed) is the knobs.

I think I’d like to switch to the “normal” cream chickenheads, because (1) they’re much easier to see in low lighting conditions, (2) they don’t come as close to the switches between them (and so are harder to bump), and (3) they’re more authentic looking on a tweed amp. But to this end I have a few questions:

1. There’s no set screw in the stock knobs. So do I just pull them off?
   
2. As this version is made in the UK rather than China, I assume it has quarter-inch shafts? (Will I need a shim?)
3. Should I just buy the knobs from Fender (perhaps via a seller on Amazon), or does anyone know of a better place to get them? I’ve seen a few different brands & styles of “chickenhead” knob floating around on the Internet, but I’d like to have the same ones Ashdown uses on other copies of this amp.

FWIW, the shade of the amp’s tweed is slightly different from that of the cab (it’s a little grayer, almost greenish). I suspect this may be one of the last of its kind Ashdown built, and that’s why it uses different tweed / knobs. I bought it from their website directly, for only about 900 USD including the cab and shipping — which was a pleasant surprise, given that the Little Stubby for example retails at major outlets for a thousand and a half with no cab! It took them a few weeks to get around to shipping it, but once they finally did it arrived in just a few days. Maybe they actually built it for me last minute, from leftover parts? I don’t know; but it is brand new, and (so far) unmodified. The knobs just aren’t what I was expecting, is all.

I’d appreciate any observations or tips you may have. And if there’s anything else you need to know, just ask. Cheers!

@Nuage420 may be able to point you in the right direction. He put red chickenheads on an LB30. For the record I own a Mk1 and Mk2 (UK Custom) LB30 and both have the round knobs without a set screw. The problem is your amp may use different pots...so there will be some risk.

 

[Nuage420]

@TonetotheBone . You can easily measure the shaft or order both sizes. A dozen knobs on Amazon rubs about $10. To remove just pull with fingers or run a shoelace or the like under the knob and pull it off.

 

[Dynacord]

On the Chickenheads, just regular 1/4" (6.35mm) on my Little Stubby and CTM-100 (both UK made) so I would guess it's the same. 6mm don't fit.

However, as yours are without set screws it would be interesting to pull one of the knobs to see it the pots are split shaft or solid shaft. Push on knobs are often the smaller size and used on split shafts. Mine all have solid shaft pots (including the older ABM with round black knobs - those have set screws as well).

Also Ashdown sells replacement knobs on their site in the "spares" section. As you bought the amp from them directly it could be worth asking them - they've had really good support IME and they might just give them to you if they know you would prefer the others.

 

[TonetotheBone]

Thanks, everyone for your replies!

But $900 US sounds a sharp price for Amp and Cabinet

I purchased it back in May of this year. From the order confirmation, FYI:

CTM-30-Tweed: £415.83
CTM 112-T-250 Tweed: £207.50
Shipping: £113.00
Total: £736.33 GBP

(So currently $879.73 USD; IIRC it was $903.69 back then. I guess that’s a normal fluctuation? I don’t know.) Even with the high shipping cost, it was quite a deal! I still can’t believe it.

All I know is, I'm not buying any of this without a couple of pictures

Here’s one I just took with my phone:

(The cab has feet on the side, too.) You can clearly see the knobs. (Which is more than can be said late at night, lol.) As for the different shade of tweed, it’s barely noticeable in this photo; the amp just looks a bit darker than the cab, is all.

@Nuage420 may be able to point you in the right direction. He put red chickenheads on an LB30.

Thanks for the tip. I actually saw that post and considered contacting him; but as I’m new here, a general appeal seemed more appropriate than a direct one. Plus it can’t hurt to hedge your bets, right?

The problem is your amp may use different pots...so there will be some risk.

By risk do you mean pulling the knobs off could damage them? (My hesitation in this regard is what prompted my first post.) Or just that I might order the wrong style of knob if I don’t measure them myself?

#s 173 & 174: Great suggestions, and thank you both. I guess it can’t hurt to just ask Ashdown! If I find anything out of the ordinary along the way, or do in fact get freebies, I’ll be sure to let you know.

 

[Wasnex]

By risk do you mean pulling the knobs off could damage them? (My hesitation in this regard is what prompted my first post.) Or just that I might order the wrong style of knob if I don’t measure them myself?

#s 173 & 174: Great suggestions, and thank you both. I guess it can’t hurt to just ask Ashdown! If I find anything out of the ordinary along the way, or do in fact get freebies, I’ll be sure to let you know.

I don't think damage is likely as long as there are no set screws, and you don't apply too much force. The risk is you will order incompatible knobs and have to deal with the hassle and cost.

 

[TonetotheBone]

Thanks for clarifying.

The volume knob wouldn’t budge when I pulled on it, but came right off with the shoelace method. (Whew.) It appears to be a quarter inch (rounding up?), and is definitely split shaft:

So far I have received no reply from Ashdown. (Maybe I should call instead of emailing; but as they’re in the UK and I’m in California, it may be tricky to arrange a good time to do so.) I found the relevant page on their site, but they appear to be sold out: [Invalid or Expired Link Removed]

I don’t mind just buying the knobs from Amazon or somewhere. But since they’re split shaft, should I be looking for push-on knobs?

 

[Wasnex]

Thanks for clarifying.

The volume knob wouldn’t budge when I pulled on it, but came right off with the shoelace method. (Whew.) It appears to be a quarter inch (rounding up?), and is definitely split shaft:

View attachment 4742838

So far I have received no reply from Ashdown. (Maybe I should call instead of emailing; but as they’re in the UK and I’m in California, it may be tricky to arrange a good time to do so.) I found the relevant page on their site, but they appear to be sold out: [Invalid or Expired Link Removed]

I don’t mind just buying the knobs from Amazon or somewhere. But since they’re split shaft, should I be looking for push-on knobs?

It may take a few days to get a response. AFAIK the email is sent to a portal rather than directly to the tech department. I believe it's evaluated before being forwarded. So it can take a few days to work through the system.

 

[Nuage420]

I emailed them s few weeks ago and still haven't received a response.

 

[Nuage420]

Thanks for clarifying.

The volume knob wouldn’t budge when I pulled on it, but came right off with the shoelace method. (Whew.) It appears to be a quarter inch (rounding up?), and is definitely split shaft:

View attachment 4742838

So far I have received no reply from Ashdown. (Maybe I should call instead of emailing; but as they’re in the UK and I’m in California, it may be tricky to arrange a good time to do so.) I found the relevant page on their site, but they appear to be sold out: [Invalid or Expired Link Removed]

I don’t mind just buying the knobs from Amazon or somewhere. But since they’re split shaft, should I be looking for push-on knobs?

I bought my knobs off of Amazon