View Full Version : Help setting up Debut III turntable and Cambridge A1 MKIII Amp


therealmungo
03-01-2012, 03:35 PM
Hi there,

I'm trying to set up my new purchases but could use some help!

Firstly, After buying the Cambridge A1 MK3 SE I read that the Cambridge A1 doesn't have a phono stage.. So it was my understanding that I'd need to run the turntable through a Phono Pre-Amp to get any real audible sound from it?

Well after trying this setup I got nothing but distortion and mess.. So out of curiosity I tried the turntable just plugged directly into the amp's Phono inputs and it seems to work perfectly. Plenty loud enough, clear quality..

Does this mean the amp DOES have a phono stage built in it or will I be harming the amp/turntable/cartridge by doing this?

Secondly.. I'm trying to set up my Debut III with a new ortofon Red 2M Cartridge. I had an issue with the ground screw on the tone-arm so I had to replace it with a slightly bigger screw. This seems to have added too much extra weight to the tone arm so the counterweight isn't heavy enough now.. I've used my Shure Tracking Weight gauge and set it to 1.8g as stated by the ortofon booklet but I just wanted to know if this will suffice for now? I'll probably get a heavier counterweight in future but funds are tight at the moment!

I also can't seem to set the anti-skate weight correctly.. The needle pulls to the center regardless of which notch the anti skate weight hangs from. Could this be due to the heavier tonearm? would a heavier counterweight help or maybe a heavier anti skate weight?

Any help would be greatly appreciated?

Dr Tinear
03-01-2012, 05:20 PM
Your amp appears to have the optional phono preamp built in, so you don't need an external phono pre. If it's working well and sounding good, don't worry; you won't break anything by running the turntable straight into the amp's phono input.

I don't have any experience with the Debut III. Perhaps another AK'er will be able to offer some advice on making it work with the new Ortofon cartridge.

Bob_in_OKC
03-01-2012, 07:30 PM
Most amps that have inputs marked "phono" have an internal phono stage; meaning an external phono stage should not be used unless you use it on one of the non-phono inputs.

As long as you can get the tracking force within the range recommended for your cartridge, it is not necessarily a problem that you can't balance the tonearm to zero. The gauges are more accurate than the Pro-Ject counterweight, anyway...in my experience. The heavier counterweight might help it track better.

The needle should pull to the center a little bit. If you set it on the ungrooved area around the label, the needle should start riding in at a similar speed to the way it does when it's in the runout groove through that area. I would put it where the Pro-Ject manual recommends, unless it causes mistracking, distortion or channel imbalance.

Putz
03-01-2012, 07:59 PM
http://www.youtube.com/watch?v=1MIK9WcSDtU

This video might help. If you search on youtube there are some other videos including one where a cartridge is switched out. Didn't watch that one so no idea if it's any good.

Anti Skate usually is attached in the middle groove but I believe you vary that based on VTF of Cart you're using.

petehall347
03-01-2012, 08:15 PM
link to your amp ...http://www.hi-fi-insight.com/cambridge-audio-a1-integrated-amplifier.html
it has mm phono in .. as an optional extra ...i do however suspect your tt has a built in pre amp ...what is the input on the amp label where you plugged in the tt ?

therealmungo
03-02-2012, 02:50 AM
Hi, the turntable has no phono stage so I guess I lucked out and my amp has been upgraded!

I led to believe the anti skating should make it run on the blank vinyl without straying to the left or right? Interesting..

I'm having a slight issue with the ground connections, where other than the tone arm could I test/re-solder ground wires to?

After a good few hours play I'm finding that although clear at the begging of the record, it seems to distort more towards the center.. what could cause this?

Also im getting reasonable amount of background noise (hiss cracks and pops) its better on brand new vinyl but I was wondering if anything I can set up can reduce this?

I've tried using the protector and adjust the cartridge to be as parallel to the lines as possible. The tracking force is set correctly and the anti skate is set as according to the manual but it seems to pull quite fast to the center..

When the track has finished and the needle gets pulled into the center groove, will that damage the needle at all if its left running for a short while?

Thanks

Neosonic
03-02-2012, 04:20 AM
Where did you get the idea that there is a ground screw on the tonearm? The only screw on the tonearm is for adjusting azimuth and is to be loosened only for that purpose and then re-tightened. I'm not understanding what your grounding issue is about. Can you better explain your difficulty?

Hiss, cracks, and pops are a sign of dirty records. Lots of threads on here about how to clean dirty records.

I'm not sure what you mean when you say "it seems to pull quite fast to the center". The fact that you're hearing distortion on the inner grooves suggests that cartridge alignment is off. Anti-skate being too high may also contribute to this.

Allowing the needle to remain in the run-out groove for a short period of time won't hurt anything. It doesn't help anything either, so I usually remove it as soon as I can.

Bob_in_OKC
03-02-2012, 08:24 AM
I led to believe the anti skating should make it run on the blank vinyl without straying to the left or right? Interesting..

If the stylus will ride standing still in the blank vinyl at the center of the record you have too much anti-skating force. It's a somewhat complicated discussion, but if the stylus rides inward on the blank vinyl at the center of the record, that's good. You might even want to try the anti-skating on a lower setting, as indicated in the replies others are offering.

therealmungo
03-02-2012, 09:09 AM
Where did you get the idea that there is a ground screw on the tonearm? The only screw on the tonearm is for adjusting azimuth and is to be loosened only for that purpose and then re-tightened. I'm not understanding what your grounding issue is about. Can you better explain your difficulty?

Hiss, cracks, and pops are a sign of dirty records. Lots of threads on here about how to clean dirty records.

I'm not sure what you mean when you say "it seems to pull quite fast to the center". The fact that you're hearing distortion on the inner grooves suggests that cartridge alignment is off. Anti-skate being too high may also contribute to this.

Allowing the needle to remain in the run-out groove for a short period of time won't hurt anything. It doesn't help anything either, so I usually remove it as soon as I can.

hi there,

The screw im talking about is about 10-20mm behind the cartridge on the underneath of the tone arm. The black ground wire coming out of the tone arm was soldered to it. Whether this is a diy mod from a previous owner or not I dont know.. it actually has a bit of ground hum with this attached anyways :scratch2: any ideas on how to locate the grounding issue?

Do the project debut III's have this ground screw or is it a mod someone has done?
where should the tonearm ground wire get soldered to?

The pull I'm referring to is the anti skate, I'm experiencing some distortion on the inside tracks so not sure how to set this correctly?

will putting the weight on the notch nearest the cartridge create more or less anti skate?

Thanks guys!

Neosonic
03-02-2012, 12:55 PM
Okay, I think I have a better picture of what's going on now. The soldered ground wire should be fine. Is your TT located near your amp? They can pick up hum from the transformer in the amp. There may be other causes for the hum but that's the one that comes to mind first.

The notch nearest the cartridge will give the least anti-skate.

therealmungo
03-02-2012, 02:11 PM
Okay, I think I have a better picture of what's going on now. The soldered ground wire should be fine. Is your TT located near your amp? They can pick up hum from the transformer in the amp. There may be other causes for the hum but that's the one that comes to mind first.

The notch nearest the cartridge will give the least anti-skate.

Okay thanks for that! Much appreciated. It's sitting on top of my amp at the moment as I have nowhere else to place it yet.. there's definitely a difference in sound when I touch the screw or the TT's ground connector that's screwed into the amp.. What is the best way to check for ground problems? I have access top a multimeter and soldering iron so it'd be good to get it as good as it can be!

As far as the distortion goes.. using my protractor. I've placed the needle on both points and tried to get the cartridge relatively parralel to the lines at both points.. Am I right in thinking that by doing this I have also set the "overhang" correctly as well?

I've set the anti skate to the middle setting as directed by the manual, And I've ordered a heaver counterweight to compensate for that larger screw but it seems a bit strange because the screw is only ever so slightly larger than the previous one..

Is it normal that when I brushed my hand past the cartridge and made contact with one of the connections on the back of it that it made a loud buzzing noise?

Cheers

therealmungo
03-02-2012, 04:50 PM
After playing around with the anti skate weight it seems to be behaving within an acceptable range.

Sounds good, Just a little over-crackly sometimes.. Buy once the music starts there's hardly any noticeable background noise.

Only thing that's bugging me now (ASIDE from the questions above..) Is that the anti skate weight actually swings slightly when a record is playing, therefore it's going to be pulling the tonearm as it swings ever so slightly?

Should the weight be perfectly still/how do I make this happen?

Neosonic
03-02-2012, 06:12 PM
Yes, having the TT sitting directly on top of the amp is a bad thing to do. Directly next to the amp is essentially the same thing, especially if there is a transformer on that side. I would think that the ground connections are fine as they are. Any hum at this point is due to the proximity of the amp and TT.

Yes, alignment automatically adjusts overhang.

The supplied counterweight is good for cartridges weighing from 3.5 - 5.5 grams (per the manual). Your cartridge weighs about 7.2 or 7.5 grams, so it needs a heavier weight.

Try lowering the anti-skate and see if that makes a difference.