Suitable SUT or Head Amp for SPU #1

[kininigin]

I’m thinking of purchasing a SPU #1 to scratch an itch, in trying a MC cartridge. I don’t really know about either SUT’s or Head amps, so unsure what would be suitable.

Any suggestions will be appreciated. Budget is around £2-300
I can stretch a bit further if it would be warranted.

Some specs on the SPU

Internal impedance, DC resistance – 2 ohm
Recommended load impedance > 10 ohm

[scotty38]

I have an Ortofon Type 2-15K SUT made specifically for these cartridges if you fancy that. Way cheaper than £600 too :-)

Edit, sorry £6-700 was the full amount but still way in budget regardless....

[Ammonite Audio]

In short, most 20x ration SUTs will be suitable for SPUs, and by far the best results I've had here have been with SUTs rather than MC headamps, but clearly some are better than others. I can only talk about those products which I have heard or which I sell. Easily the best fixed ratio SUT that I've heard is the Phasemation T-300, which at £550 does not quite fall in the quoted price range for cartridge and step up, but it is a pretty amazing performer by any standard, let alone its relatively sensible price; the Ortofon ST-7 is designed for SPUs and other Ortofon stereo cartridges and is a little cheaper at £450 - it is a decent performer but the Phasemation does give quite a bit more musical bang per buck.

[kininigin]

I have an Ortofon Type 2-15K SUT made specifically for these cartridges if you fancy that. Way cheaper than £600 too :-)

Edit, sorry £6-700 was the full amount but still way in budget regardless....

Thanks for the offer, will pm you.


In short, most 20x ration SUTs will be suitable for SPUs, and by far the best results I've had here have been with SUTs rather than MC headamps, but clearly some are better than others. I can only talk about those products which I have heard or which I sell. Easily the best fixed ratio SUT that I've heard is the Phasemation T-300, which at £550 does not quite fall in the quoted price range for cartridge and step up, but it is a pretty amazing performer by any standard, let alone its relatively sensible price; the Ortofon ST-7 is designed for SPUs and other Ortofon stereo cartridges and is a little cheaper at £450 - it is a decent performer but the Phasemation does give quite a bit more musical bang per buck.

Thanks for the suggestions, they sound interesting, although as you say slightly over budget. Still not entirely sure about going the MC route as I’ve never heard one and will be a fairly substantial outlay for a punt on something. It is an itch I want to scratch though, so why not go for it I say.

[scotty38]

Pm replied to.....

[kininigin]

So Martin has kindly offered his Ortofon sut to me at an attractive price but have also noticed a Fidelity Research FRT-3 for sale as well. Would that also suit the SPU #1 and if so, how do the two SUT's compare?

[Miller]

Had a SPU G with Garrott Brothers stylus and the FRT-3 & STM-72 at hand as well as other SUT's/head amps due to at the time being knee deep.... Near 15 years ago but I preferred the STM between the two as the FRT-3 rolled off the higher frequency.... The STM also had more gain if my memory serves me right....

[kininigin]

Had a SPU G with Garrott Brothers stylus and the FRT-3 & STM-72 at hand as well as other SUT's/head amps due to at the time being knee deep.... Near 15 years ago but I preferred the STM between the two as the FRT-3 rolled off the higher frequency.... The STM also had more gain if my memory serves me right....

Interesting, I guess the Ortofon SUT should match well with their own cartridges.

I have a few more questions regarding the SPU, how do you adjust overhang?

Will it be a decent match with my Jelco arm?

If I go for either SUT, what other cartridges would go well with them, if for instance I’m not liking the SPU and would like to try a different MC?

[Smegger68]

Interesting, I guess the Ortofon SUT should match well with their own cartridges.

Oh yes.

I have a few more questions regarding the SPU, how do you adjust overhang?

You don't really.

Will it be a decent match with my Jelco arm?

The 750D arm to pivot length is 214mm. The ideal for an SPU (on a 9" arm anyway) is 212mm. I wouldn't expect 2mm to make a lot of difference, especially if you get a spherical tipped one.

If I go for either SUT, what other cartridges would go well with them, if for instance I’m not liking the SPU and would like to try a different MC?

I tried my Benz through my Ortofon SUT and it worked very well, though the Lentek head amp gives it mopre oomph. YMMV quite a bit TBH.

[Barry]

I have a few more questions regarding the SPU, how do you adjust overhang?

You don't really.

Will it be a decent match with my Jelco arm?

The 750D arm to pivot length is 214mm. The ideal for an SPU (on a 9" arm anyway) is 212mm. I wouldn't expect 2mm to make a lot of difference, especially if you get a spherical tipped one.

The Ortofon SPU was designed to be used in Ortofon arms, where presumably the correct overhang and offset angle was achieved. Because of that, there is no provision to adjust the overhang within the headshell of SPU cartridges. If an arm other than one made by, or for, Ortofon is used, then the alternative arm needs to have a sliding bedplate at the arm pivot end. SME have this facility (as do a very few others). The sliding bedplate allows one to alter the turntable spindle to arm pivot distance, and in doing so the overhang and ofset angle are adjusted at the same time.

Thus one can, in principle, use an SPU in a non-Ortofon arm. However there is a futher subtle complication: in an Ortofon SPU cartridge the stylus to headshell bayonet flange distance is 52mm. With all other headshells having the EIA bayonet fitting, the cartridge stylus to bayonet flange distance is assumed to be 50mm. That is where the 2mm discrepancy comes in, leading to slightly incorrect arm-cartridge geometry. Whether one can hear the results of this discrepancy is a somewhat moot, but I would prefer to achieve correct arm-cartridge geometry in the first place.

[kininigin]

I tried my Benz through my Ortofon SUT and it worked very well, though the Lentek head amp gives it mopre oomph. YMMV quite a bit TBH.

That’s a cart I don’t really know anything about but have heard of them. Good to know it can work with the Ortofon though.

[kininigin]

The Ortofon SPU was designed to be used in Ortofon arms, where presumably the correct overhang and offset angle was achieved. Because of that, there is no provision to adjust the overhang within the headshell of SPU cartridges. If an arm other than one made by, or for, Ortofon is used, then the alternative arm needs to have a sliding bedplate at the arm pivot end. SME have this facility (as do a very few others). The sliding bedplate allows one to alter the turntable spindle to arm pivot distance, and in doing so the overhang and ofset angle are adjusted at the same time.

Thus one can, in principle, use an SPU in a non-Ortofon arm. However there is a futher subtle complication: in an Ortofon SPU cartridge the stylus to headshell bayonet flange distance is 52mm. With all other headshells having the EIA bayonet fitting, the cartridge stylus to bayonet flange distance is assumed to be 50mm. That is where the 2mm discrepancy comes in, leading to slightly incorrect arm-cartridge geometry. Whether one can hear the results of this discrepancy is a somewhat moot, but I would prefer to achieve correct arm-cartridge geometry in the first place.

Yes it was noticing that there was no obvious ability to change overhang that prompted me to ask the question. Well I won’t be changing my arm which is in a fixed position. As you say, is the 2mm difference noticeable? I guess I could add a couple of washers on the head shell bayonet to gain the 2mm? Either way it’s going to be a suck it and see thing.

[Shovel_Knight]

However there is a futher subtle complication: in an Ortofon SPU cartridge the stylus to headshell bayonet flange distance is 52mm. With all other headshells having the EIA bayonet fitting, the cartridge stylus to bayonet flange distance is assumed to be 50mm.

I don't know about ALL other headshells, but at lest Technics specifies flange to stylus tip distance of 52 mm for their tonearms. Fidelity Research only specifies the distance from the stylus tip to the front of the headshell (7mm), but I just measured my stock FR headshell with calipers and it's 59mm from the flange to the front which means that flange to stylus should be 52mm as well.

[kininigin]

So bit of an update. Ortofon type 2-15k has now been bought (thank you Martin) and have now ordered a SPU #1 (thank you Hugo-Ammonite Audio) so just need to get a heavier counter weight for my Jelco and I’ll be set to go.

Looking forward to my first experience of MC cartridges.

[scotty38]

Nice one, my SPU came from Hugo too, great bloke to deal with.

[kininigin]

Nice one, my SPU came from Hugo too, great bloke to deal with.

Yes great service, in fact, I may have it by tomorrow. Which means I need to get my skates on and get a counterweight soon.

[Ammonite Audio]

Yes great service, in fact, I may have it by tomorrow. Which means I need to get my skates on and get a counterweight soon.

I'm sure you could improvise something in the way of extra counterweight mass!

[kininigin]

Will start looking in work van for something suitable. Not sure what though. Did have some scrap led not too long ago but scrap man has had that.

[kininigin]

So the the SPU #1 arrived yesterday. Very speedy delivery. I had ordered a heavier counterweight as well, which I am still waiting for. I intended to wait for that before trying the SPU but curiosity got the better of me. My solution to my problem, was to cello tape 5 10p coins around the weight, which added 31grams or so and miraculously fitted perfectly around.

I have played about 20 sides so far of various types of music and I can say that I’m very pleased with the SPU. Sounds very clean and open and with a great tone to it. Bass goes deep and sounds full. The mids are expressive and draw you in. If I had to use one word to describe the SPU it would be flow. Everything just flows at you in a very musical natural way.

I think I am a MC convert.

[anubisgrau]

well it has to sound better than shure sc35!

[scotty38]

Great news that it's all working out, nice one!

[kininigin]

well it has to sound better than shure sc35!

Well I've been a very happy user of the Shure, which is more capable than you may think! In fact I've been perfectly happy with it for the last eight years. If it wasn't for the fact I wanted to hear what a MC can do, then I would have no issue using the Shure for another 8yrs and beyond.

Not saying it's the best cartridge since sliced bread but it does so much well that I simply haven't felt the need to try anything else, until now of course.

[kininigin]

Great news that it's all working out, nice one!

Thank you Martin, I am certainly enjoying the SPU that's for sure. I am now of course thinking what a modern sut would bring to the party ha.