Buying a 2nd hand amp

**Aant** · 01-30-2013, 08:31 AM

Hi everyone,

I need your wisdom once again if you do not mind:

This week-end I will try a 2nd hand amp (a Mesa Boogie Studio Caliber DC-2 Combo). The problem is: this amp is all tube and I don't know what to check, verify, pay attention to in order not to be deceived, scamed.

Can you please assist me?

Again, thank you very much in advance for your help.

Mesa Boogie Studio Caliber DC-2 Combo:
The add says 25W, the manual shows 20W
2 x EL84
6 x 12AX7
For those who are interested the manual is right here: http://mesaboogie.com/manuals/Studio%20Cal%20DC-2.pdf

Side question: do you think this amp is loud enough to play in a Band?

**OldRocker** · 01-30-2013, 10:23 AM

Hi Aant,,
I would start with the obvious and check the general condition. If it looks like it has been slung around in transit to gigs etc, this could be a problem. Just check that everything works and the controls are not noisy when turned. Make sure you can get the sound you are looking for and that there is no loud hiss or hum at all volumes, most amps have some background noise. Make sure there is no loud click or pop when switching the amp off as this often denotes a condenser problem. I can't think of anything else you can easily check. In answer to your side question, no if it is a heavy metal band, yes if it is a jazz combo or small band. Good luck.

**SamBooka** · 01-30-2013, 10:44 AM

yep.. Like OR says. it is a fairly recent amp (not like buying something pre 1995)

No pops hisses fuzzes or buzzes. If you like it its yours.

Some amps DO pop when you start them or shut them down.. google first to see if this amp is supposed to do it.

**Aant** · 01-30-2013, 10:52 AM

Originally Posted by OldRocker

Hi Aant,,
I would start with the obvious and check the general condition. If it looks like it has been slung around in transit to gigs etc, this could be a problem. Just check that everything works and the controls are not noisy when turned. Make sure you can get the sound you are looking for and that there is no loud hiss or hum at all volumes, most amps have some background noise. Make sure there is no loud click or pop when switching the amp off as this often denotes a condenser problem. I can't think of anything else you can easily check. In answer to your side question, no if it is a heavy metal band, yes if it is a jazz combo or small band. Good luck.

Thanks for your reply OldRocker.
I will indeed pay attention to the general condition of the amp, however I would not have thought of the noise that could come out when turning the controls or the click/pop when switching the amp off. I'll also verify if there is a loud hiss/hum at different volumes.

My question may seem a bit stupid but I have not owned an amp for years, last one was a transistor combo that ended broken eating dust.

**oldane** · 01-30-2013, 11:43 AM

Originally Posted by SamBooka

Some amps DO pop when you ..... shut them down.

Yes, that's very normal for solid state amps. Turn it off and wait 1 ... 2 seconds and a soft pop is heard. However, this one is a tube amp.

**Aant** · 01-30-2013, 12:24 PM

Thank you Sambooka and oldane, I'll pay attention to an eventual pop as I could not find on the web that this would be a standard behaviour for this amp.
Actually, I thought that this would be ok to hear this pop, even for a tube amp. Glad I asked!

**OldRocker** · 01-30-2013, 03:08 PM

Just to clarify, the pop I am talking about on switch off would be quite loud on a faulty valve amp and not just a gentle sound as heard on most solid state amps.

**mad dog** · 01-31-2013, 12:53 PM

You also want to pay attention to the general noise floor of the amp ... how much background noise there is even before volume goes up. Some amps are quieter than others. The presence of some noise says nothing, could be just how that amp is. But if it's real noisy, that's probably not the healthiest amp. Whatever the problem - old caps, sockets in need of cleaning, retensioning, whatever - shouldn't be your responsibility.

I've often encountered noisy preamp tubes in amps I'm thinking of buying. These things happen. For example, if you hear a loud squeeling with volume up, could be a microphonic tube. Tapping the tube with volume up, but not high, may reward you with a certain ringing sound. That's how you know which tube is the problem. This kind of thing is a judgement call. Tubes are easily swapped. I'm comfortable doing that stuff, but you may not be. You really shouldn't have to be. If you're hearing strange noises and the seller can't fix it on the spot, probably time to move on.

MD

**Aant** · 01-31-2013, 01:43 PM

Originally Posted by mad dog

You also want to pay attention to the general noise floor of the amp ... how much background noise there is even before volume goes up. Some amps are quieter than others. The presence of some noise says nothing, could be just how that amp is. But if it's real noisy, that's probably not the healthiest amp. Whatever the problem - old caps, sockets in need of cleaning, retensioning, whatever - shouldn't be your responsibility.

I've often encountered noisy preamp tubes in amps I'm thinking of buying. These things happen. For example, if you hear a loud squeeling with volume up, could be a microphonic tube. Tapping the tube with volume up, but not high, may reward you with a certain ringing sound. That's how you know which tube is the problem. This kind of thing is a judgement call. Tubes are easily swapped. I'm comfortable doing that stuff, but you may not be. You really shouldn't have to be. If you're hearing strange noises and the seller can't fix it on the spot, probably time to move on.

MD

Great, thanks for the information!

Speaking of valves, Orange has presented its Vavle Tester during NAMM this year, it looks like an interesting little product:
VT1000 - Orange AmplificationOrange Amplification

**rpguitar** · 01-31-2013, 04:56 PM

I owned a DC-5 for a while and just sold it for $400. That's a 50W version of the same basic beast. LOUD AS HELL. Yours will be, too. There's not much to check technically that's easy to test at a quick audition. It likely has a standby switch in addition to power. Put it in standby, turn it on, and after a minute or so, take it out of standby. To shut down, put it in standby, wait a moment, then power off. Check the pots (controls) for noise. Mine developed that after sitting for a couple of years. Can be taken care of with spray contact cleaner. Does the pilot lamp work? Reverb? Etc.

Of course you don't want to be hosed, but this is not too risky a situation most likely. Good luck.

**Aant** · 02-01-2013, 08:05 AM

Originally Posted by rpguitar

I owned a DC-5 for a while and just sold it for $400. That's a 50W version of the same basic beast. LOUD AS HELL. Yours will be, too. There's not much to check technically that's easy to test at a quick audition. It likely has a standby switch in addition to power. Put it in standby, turn it on, and after a minute or so, take it out of standby. To shut down, put it in standby, wait a moment, then power off. Check the pots (controls) for noise. Mine developed that after sitting for a couple of years. Can be taken care of with spray contact cleaner. Does the pilot lamp work? Reverb? Etc.

Of course you don't want to be hosed, but this is not too risky a situation most likely. Good luck.

Thanks a lot, that is actually reassuring to read. I guess I worry a bit too much...

It's funny that you mention you sold your DC-5 for $400, in this part of Europe the average price for a second hand DC-2 is, as far as I can see, around €700 (~ $955). A DC-5 would be negociated around €850 (~ $1160)...

**Aant** · 02-04-2013, 12:33 PM

Well, I tested the amp on Saturday and gladly went back home with it: great tone, very quiet amp, the controls work well without any noise, the overall condition is very good, it made me a happy man...

... until I tested the headphones and record outs: the first does not work and the later barely (extremely low volume, no clean tone as it is almost immediately overdriven). I could not try those features beforehand, I wrongly assumed that, considering the overall condition of the combo those outs were fine. The seller proposed anyway to buy the amp back, so everything will be in order at the end of the day.

I anyway asked an amp technician to provide me with an estimation of the cost to have it fixed.

Thanks again for your help on this guys.

**TieDyedDevil** · 02-04-2013, 04:58 PM

Originally Posted by Aant

... until I tested the headphones and record outs: the first does not work and the later barely (extremely low volume, no clean tone as it is almost immediately overdriven).

Wait: what?

This amp does not have a headphone output. Are you certain that you're using the various outputs properly?

**Jonathan0996** · 02-04-2013, 08:24 PM

Right. The amp doesn't have a headphone out. I seriously doubt there's anything wrong with the record out if the rest of the amp is working fine. You might try having a look at the owner's manual to make sure you're using it correctly:

http://www.mesaboogie.com/manuals/Dual%20Cal%20DC-5.pdf

**Aant** · 02-05-2013, 05:54 AM

The seller had the same reaction, which led us to quite a tensed conversation as you can imagine. As he could not believe me, he sent an e-mail to Mesa Boogie customer support, who confirmed some DC-2s come with such a feature. He never noticed it was there as he was so convinced about its absence.

The DC-2 I bought definitely has this headphone output (there is an output with 'Headphones' written above it), it is actually located right below the fuse. I have downloaded the manual and, indeed, the information does not appear on it. I'll try to remember to post a picture of it in this thread.

Concerning the silent record output: I have actually plugged a normal jack in this output to my computer, via an external audio interface (Apogee Duet), and used the silent speaker feature. The problem is that the volume is very, very low, I have to substantially increase the volume on the amp to hear something. Consequently, on the rythm channel, I can not get a clean sound, it gets overdriven quite rapidly. I may be wrong but this does not seem to function properly. Also, considering the fact that this amp is loud (euphemism), I would assume that the volume of the record output would follow the same trend. However, there is one valve that looks dead, maybe it has an impact (although if I'm correct it is one of the six 12AX7, not a EL84).

I'm still thinking about keeping the amp to have it repaired and ask the seller for a discount. Do you think it could be easily fixed? And would it be expensive?

EDIT: I found this picture of a DC-2 with a headphones output --> http://i6.photobucket.com/albums/y209/MyCyberFix

**TieDyedDevil** · 02-05-2013, 12:04 PM

I stand corrected.

I always found M/B tech support to be highly knowledgeable about their products. I'd start with them to get more info regarding the problems you're experiencing and their possible solutions.

Good luck.

**Aant** · 02-06-2013, 06:41 AM

I met the seller yesterday evening to discuss the issue. As he intends to fix it himself, I chose to be reimbursed. I expected the amp to be thoroughly checked by a technician, who could also have a look at the record output that behaves weirdly.

As mad dog says, time to move on...