Optimo or ZD5 TL - that is the question...

[JonnyW]

I've only recently started looking into speaker building after a number of house moves (including one from the UK to Australia). I've taken more of an interest since the last move, as it appears that "brand name" speakers are prohibitively expensive here. I don't profess to know much about crossover design and the attributes of the multitude of drivers available (and neither do I have the time to learn), so am looking for a design to reproduce. Having renovated two houses whilst living in the UK I have the required DIY skills but not necessarily all the tools with which to construct the cabinet. Crossover construction is not a problem.

Because we move around a lot, and also because my wife is not accepting of certain "audiophile" necessities, I have the following requirements:
1. Floor-standing design around 1m tall
2. accepting of close to wall placement i.e. front baffle less than 1m from rear wall
3. Simple enclosure construction i.e. no sloping or multi-angled baffles
4. From an acoustics perspective, I don't have a requirement for chest slamming bass or anything like that, but the speaker must be able to carry a tune and 'time' well. Front-end is all Naim. I listen to a wide range of music with a preference for acoustic material (although this might well have been shaped by my previous speaker's qualities).

With the above requirements in mind, I think either Tony's Optimo design or the TL version of Zaph's ZD5 (see Zaph's blog for details) might well be for me. I like that they're "only" a two-way (my previous speaker was an MTM and unless you were sitting on the floor it never seemed coherent), my wife likes the designs, the enclosure construction is nice and easy, and I think the transmission line design should allow the speaker to be easy to place and room friendly.

I was initially concerned about the cost of the Scan-speak tweeter, but E-mails between myself and Tony (thanks for all your advice ) has demonstrated that I can use the same Vifa XT25 tweeter in the Optimo as used in the ZD5 with minor crossover adjustments. As a result, the cost of each unit is practically the same.

What I now need to do is to decide which design to go for. Whilst both being TL designs the approach is quite different. Tony's cabinet has a long folded TL with an Fs of 35-38Hz whilst John's (& Dave Little's) design is a straight pipe with an Fs of 65Hz. Other differences are in the size of the woofer. With the extra woofer area AND the longer pipe tuned to the lower frequency, am I right in thinking that Tony's design would produce a lot of bass, or would the floor reinforcement available from John's design mean there isn't much difference in reality. I guess this will be somewhat affected by floor covering as well. If it makes any difference, the current house has a suspended wooden floor, but future houses will likely by tile covered concrete.

I've waffled on enough now, but in short, I'm looking for a little guidance. I know John's design is very new so there probably aren't any "out there", but I'm interested in people's thoughts none the less.

PS. I'm new so be nice please

Thanks, Jon

[sreten]

Hi,

I've heard a Naim system driving a pair of Rega Naos TL's.

Larger driver and longer line = louder and deeper extension bass.

The sensitivity of the two systems is a major issue.

Optimo all the way I think, from reading your requirements.

/sreten.

[JonnyW]

Thanks Streten,

Are you suggesting the Optimo because of my comments on the bass response? If so, I'm not necessarily looking for 'big' bass, I just wanted to understand that this was the likely outcome - which I guess you've confirmed.

My previous speakers (also used on a suspended wooden floor) always seemed to 'boom' quite a bit and i want to avoid this with the new speakers. Some of this effect may have been down to placement in my small UK lounge. Now I'm down under I have a lot more space which should help.

Hope that makes sense

[sreten]

Originally posted by JonnyW
Thanks Streten,

Are you suggesting the Optimo because of my comments on the bass response? If so, I'm not necessarily looking for 'big' bass, I just wanted to understand that this was the likely outcome - which I guess you've confirmed.

My previous speakers (also used on a suspended wooden floor) always seemed to 'boom' quite a bit and i want to avoid this with the new speakers. Some of this effect may have been down to placement in my small UK lounge. Now I'm down under I have a lot more space which should help.

Hope that makes sense

Hi,

Not particularly your comments on bass response.
Deep bass is not : boomy bass or lots of bass.
More placement and purpose issues.

One advantage of DIY TL's is you can stuff to suit the room.

I assume you don't want to upgrade the Naim kit anytime soon.
The ZD5's sensitivity is too low IMO to suit your requirements.

/sreten.

[JonnyW]

Thanks Streten, looks like I'll be building myself a pair of Optimo's then!

Appreciate the advice.

Cheers, Jon

[rkreim]

just seeing if you built the optimos and how do they sound ?
if you are in Melbourne may i could have a listen

[peter_m]

I'm interested in this Optimo TL design for the same reasons as the original poster. Unfortunately, my finances don't allow for the same drivers as the original plan. Let's say I want to keep the cost of all 4 drivers between 200$ and 250$US for a complete stereo pair.

Any suggestion on using less expensive drivers?

[sreten]

http://www.zaphaudio.com/audio-speaker17.html

But do not invert the drivers, /sreten.

[sreten]

Hi,

scrub that last suggestion, might not work well in that line.

/sreten.

[peter_m]

Originally posted by sreten
http://www.zaphaudio.com/audio-speaker17.html

But do not invert the drivers, /sreten.


Hi,
scrub that last suggestion, might not work well in that line.

/sreten.

Can we modify the TL to better sute the speakers you mentioned?